Lister Engine Forum

How to / DIY => Everything else => Topic started by: guest22972 on February 19, 2018, 08:58:31 AM

Title: More panels!
Post by: guest22972 on February 19, 2018, 08:58:31 AM

Continuing with what has turned out to be a solar obsession, I bought another lot of panels today.

20x250W or 5 KW.

The offerings have slowed down a bit of late with not too many coming up and most of them wanting stupid prices. That said, I did miss out on another setup of 20x 250W panels and inverter etc the other week for $400. Buyer had to take down but for that, well worth it.

This last lot of panels I got for $500. The seller had advertised them for $1500 which was well more than they were worth.  This has been working well for me. I know sales and the flip side of that is knowing how to negotiate. it's taken a little working out but is now working pretty effectively.  I put in some low ball offers, wait, come back with a slightly higher one after a week or so and they are in a lot more negotiating demeanour generally.
Of course some are just arrogant and indignant twats that stick to their stupid prices and abuse you for your offers but you see them still advertised a month later. I get a mate to send them another offer and they still stick to their unrealistic prices. Hmm, whos the time wasting idiot now 'eh?

It IS starting get get hard keeping track of what I have now.  My Dad wants me to put some on his place seeing I have now changed his mind. He thought they were bit of a gimmick but on hearing how much I'm saving on my power bill, has now given him a change of heart. I think I'll donate him my original set of 1.5Kw worth of 190's and my slightly limited but still working fine 3 kw inverter with one tracker out of action.  Regularly puts out 1900W with the array I have it connected to so will do full tilt on this lot.  There are a lot of the 180/ 190W panels around so if the 1.5kw isn't enough It will be easy to get more and bump the system another 1.5 and get him another inverter.

My plans will be to keep the existing 5.5KW on the north side of the shed, put the 4 Kw on the south side that are still sitting on the back retaining wall, the new 5KW on the north side of the house and the other 3Kw of 180's on the west side of the house.
The shed is only 5 and 13o pitch so even though the south is the wrong side for panels here down under, I have been getting very good performance out of the ones up there. I will run the numbers again to check but I think they will still be better up there than on the west side of the house.

Our power bill came in today which was interesting. I'm recovering the cost of these panels almost straight away. Instead of years with a new system, it's  one quarter's billing at worst for each set and the way I am getting them cheaper all the time, sometimes as little as 6 weeks.

The one phase I haven't been back feeding so far and only has the AC on it was by far the highest at $180. Being a 3 phase system, that means the total bill just for the Ac would have been $540 alone.  The total bill with over $100 " supply charges" was $362. Hot water was $44 which was a lot lower than I expected.  I have set up a control box now and am feeding that from the phase
I'm currently pumping the most solar into . The box has the voltage switch on it and a PWM controller limiting the 3800W element to just 1500W so the standard circuit is not overloaded.  Although the bill was low this time, I expect it will be a lot higher over autumn and winter. I'm convinced the water heater copping the afternoon sun on the 40o++ days we have had so many of here does completely neutralise any heat loss or even add to the water temp. Going to paint the thing black to make the most of this theroy.  Might even see if I can find some shiny material of some sort to put on the wall behind it and curve it round a bit.

These used panels really have been a great thing.  The ROI is so quick and they have given me a new interest and something to take my mind off things. Now I want to get this all set up for winter and the new wiring done to handle it all.
I'll look at a way to feed the other phase with the AC but other than that for heating it might just be a case of going back to the little fan heaters we used at our other house. Not exactly efficient but as long as we can keep up with the power they use, not really a concern.

For those that can get used panels, I highly recommend even a small setup plugged into the outlet. "Powerjack"  brand inverters are designed specifically for this and come in decent outputs that would make a worthwhile difference to ones consumption.
Title: Re: More panels!
Post by: BruceM on February 19, 2018, 04:39:46 PM
Amazing bargains on 250 watt panels, Glort.  That much affordable power makes me start dreaming of home hydrogen electrolysis and storage or a micro aluminum smelter.

I'm just about ready to install my upgraded 120VDC battery bank controller to better handle my upgrade to 2375 watts from 875.  I couldn't resist upgrading my individual (12v) battery regulators to new pcbs also and that was 10 plus 2 spares boards to assemble, solder, and seal by hand.  I have to wait for the wind to stop- can't think straight on windy days so it's not the time to work with 120VDC and custom electronics.





Title: Re: More panels!
Post by: BruceM on February 20, 2018, 12:16:13 AM
Part of my justification for the power increase was having power for a greenhouse.

For the climate here,  evaporative is cooling needed for greenhouses despite out elevation at 5600 ft. Our summer days are commonly 90-102F, and typically single digit humidity until August, when we have our afternoon monsoon showers.  There are hot weather crops but as luck would have it I can't eat them regularly.  Our high desert climate is a study in extremes, but passive solar greenhouse growers do fairly well except in summer. Summer greenhouse crops are heat stressed and sapped by bugs.  Outdoor growing is limited to masochists; I did it until my entire crop was destroyed by hail three years in a row after being carefully nursed in cold frames, hotcaps, wind walls, etc. through the spring. 

Evaporative cooling is a good sunny day load if your humidity is low enough to allow it.  I did find gardening to be very good therapy and I miss it.

I'm interested in hydroponics also -  as a means to reduce greenhouse bug problems since I can't be around pesticides.  It requires someone with a more technical inclination but that's me anyway.

Title: Re: More panels!
Post by: LowGear on February 20, 2018, 05:51:44 PM
Aloha glort,

Will you, in a couple of easy to read sentences, report what your utility might have to stay about your hooking all these panels up to their grid?

And then a couple more easy to read sentences report what your building permits and zoning agencies might have to say about this as well?

Casey

Also: can you do this without bringing to light their maternal genetic heritage?
Title: Re: More panels!
Post by: BruceM on February 20, 2018, 07:15:24 PM
Glort has already covered that issue quite thoroughly, Casey, and discussed it with a lawyer, which he also related on the forum.  He's probably right in that he will only get a verbal spanking if played as overzealous patriotic greenie. 

Reminds me of the "big" fines levied on large US pharma corps when they get caught in outrageous deceit (like promoting antidepressants for kids when their own unpublished data showed it would likely cause many to suicide)...those fines were a tiny fraction of their profits from same (criminal) deceit.  This is hardly in the same class and is entirely a civil contractual matter.  Glort might have to pay for a few months power...

About greenhouses, Glort.  I do like aeroponics, widely recognized as perhaps the highest producing method, but not being able to be near electric motors and being off grid makes other hydroponic methods that are less energy intensive more appealing.  While I can insulate and run pipes and remote what pumps are necessary, things like homemade version of the autopot (gravity fed only from a raised tank) start to look more appealing. Other schemes with less water movement such as Bato buckets or Nutrient Film (gutters) also use less energy- important for night and dark days where batteries must provide energy.

Because motor noises stress me greatly, I'm thinking more along the lines of the Persian windcatcher tower with passive evaporator added up near the top of the tower to have convection flow on windless summer days, which are common.   I have found some models for calculating convection driven flows and this is viable with very large passages. About 6500 CFM minimum is needed for a greenhouse of 20x40 feet.  A 24 foot (8M) tall tower with 3x6 foot ID would suffice for that flow rate.  Agriculture buildings are not inspected in my rural county so I have unfettered freedom to do as I wish.

I have an extensive library on greenhouse design and hydroponics...armchair construction is actually better suited to my present physical capabilities.  The greenhouse has been a dream project for many years.

 









Title: Re: More panels!
Post by: BruceM on February 21, 2018, 02:25:48 AM
Glort, I just remembered the hydroponic AutoPot system is an Australian invention.  Check it out:

https://www.autopot.com.au/

Clever valve for gravity flow hydroponics with no pumps or electronics needed.  Interesting invention and it's widely acknowledged success shows that cyclic watering/feeding with the right growth media provides sufficient aeration of plant roots without the energy needs of bubblers, spraying, contiuous circulation, etc.  Their special float/drip irrigation type valve doesn't allow the "pot" to get another trickled in filling of nutrient solution until the last fill has been consumed.  The same approach could be used with an electronic control system with float switch type sensors, also.

My primary interest in hydroponics is due to the widely acknowledged reduction in bug and disease problems due to the lack of soil and sterilization of growing apparatus after each crop.  (Like the glory days of your first year garden every year.) The reduction in water use is also a plus but the need for evaporative cooling makes that seem a relatively minor benefit. 






Title: Re: More panels!
Post by: ajaffa1 on February 21, 2018, 07:32:18 AM
Hey Glort, I`ve been following this thread for a while, astonished that you are able to generate that amount of power for so little investment. Your suggestion of using all this power in the garden interests me. Many years ago I was a computer geek and spent a great deal of my time building super fast computers using cheap/obsolete parts, generally this was done by overclocking the computer chips. I discovered that by using a thermocouple and pumped water cooling we could run chips at nearly twice there recommended speeds. I even built one machine on which I could run every Microsoft product ever sold as an application on a Unix based platform.

The thermocouples we used were cheap as, if I remember right they drew about 30 watts. when powered up one side became hot and the other side ice cold. I have thought for a while that these could easily be set up to harvest moisture out of the atmosphere, much the same as a cold beer glass will leave a puddle on the table in our climate. I suspect that with all the excess power you have available you could probably produce all the water you could ever use. I even considered making a prototype, basically a small solar panel driving a heap of thermocouples which you could place at the bottom of a fruit tree to automatically water it when ever the sun was shining. Crazy? probably, but I have one thing most people don`t a signed hospital release saying I am perfectly sane.

Bob
Title: Re: More panels!
Post by: ajaffa1 on February 21, 2018, 08:59:56 AM
Further to my previous post please have a look at these https://www.ebay.com.au/itm/10pcs-40x40mm-TEC1-12706-Heatsink-Thermoelectric-Cooler-Peltier-Plate-12V-TE610/262966651378?hash=item3d3a08a9f2:g:3koAAOSwVqlaMOhi

I suspect that a piece of 4" box section, raised of the ground, with some of these mounted on the inside would cause a down draft pulling in humid air which would condense on the heat pads and then drip onto the ground below. A bit of experimentation would be required to asses how many to use per panel. It would also be important to avoid getting down to the freezing point of water that could be problematic.

I have no idea how much water this would capture in a day but I have seen tables running with water from just a few cold beers.
Title: Re: More panels!
Post by: ajaffa1 on February 21, 2018, 11:37:38 AM
Hey Glort, be careful what you wish for, hope you are not in for some sort of biblical flood, I had one just before Christmas and I`m still trying to clean up the mess. On the bright side I won`t have to cut firewood for five years. Trouble with rain fall in Australia is that it lands on dead dry land and washes the top soil away, best thing you could do is drill the paddocks/gardens so some soaks in.

I saw the video of dew harvesting, very cool idea, I think it was in the mountains in Bolivia. Sadly not much dew or condensation here, just heat and humidity, that said we have had the best rainfall I have seen in the last five years. Trouble is I have to spend too much time cutting the grass and not enough time building engines and playing with my toys.

I did reply to your message, if you didn`t get my reply it`s probably due to the problems with the mail server. Please feel free to email me at ajaffa1@yahoo.co.uk, yes it`s a UK address, I kept it when I came to Oz six years ago, strangely enough I now get next to no spam email because the spammers in Oz don`t recognise my address while the ones in the UK know there is no point emailing a bloke in Australia.

Bob
Title: Re: More panels!
Post by: LowGear on February 21, 2018, 05:59:38 PM
Quote
I know I am well taxing your reading and comprehension abilities now, but why do you even ask and in this way?
Just seems like an attempt to put down what I am doing and discredit it. If it were anything else you'd be asking about the setup itself because it does not matter a fig to you what the rules are here or what I'm doing on my place.  Just a smoke screen to try and put shit on my efforts is all.
If that's what you want to do, fine, just come out and have the balls to do it up front. I care about that as much as I give a damn about the underhanded way of doing it and jealous prats going on about rules and regulations like it matters an iota to them. 

To spell it out, I don't give a Fk about idiotic and worthless rules and regs that serve no purpose other than to give bureaucrats who polish a seat with their arse a job whom have no idea what they are talking about anyway. If other people are scared of their own shadows and won't do a thing that they are told they can't and think they have to have qualified sparky in to change a fuse, Good on them.

These rules and regs are no guarantee of safety or reliability, I can point to many specific documented cases where compliance has been the CAUSE of fires and safety issues. They just changed back a rule with isolators here to what it was previously after it was worked out how many fires had been started in systems due to compliance with the "new" regulations. The fire dept were the ones who came heavy on the gubbermint to change it back after they saw an instant veritable explosion of fires on these new installs No one knows why the rules with that were changed in the first place but it was a hell of a stuff up that caused a LOT of problems that's for sure.

And if you are still with us, to prempt the next inevitable excuse for the concern about rules and regs, No, it won't Violate my insurance unless they can PROVE it was the cause of a problem.  If a fire is started by a gas leak in the house, they can't write off the claim because my solar setup isn't compliant.
Maybe where you live they can get away with that and have you bent over a table with your pants down but it does NOT cut it here. 
Unless they can prove a fire started as a result of a FAULT in my solar setup, everything else IS still covered.

My setup has more breakers and disconnects than any Compliant system and they are all rated to trip the moment something goes wrong by very tight tolerances for the power going through them. To turn it round, I'd challenge anyone to leave the protection I have in place and manipulate the rest of the system in anyway TO cause a problem if they tried. It won't happen.

But thanks for your legitimate concern.

Your right. 
Quote
I know I am well taxing your reading and comprehension abilities now, but why do you even............(the dots are my quoting our illustrious leadershipness.)

I got through the first part and your area does have some rather stupid and hidden agenda rules.  We have some too.  Not quite as stupid but all in all - Deceptive and misdirected. 

I'm behind schedule this morning.  Manana! 
Title: Re: More panels!
Post by: LowGear on February 21, 2018, 11:26:40 PM
I find your approach interesting.  Damn the torpedoes - Full speed ahead!
Title: Re: More panels!
Post by: mike90045 on February 22, 2018, 07:48:06 AM
 
Quote
There is a thought..... Do an electrolysis setup with my extra solar power and feed the oxygen to the plants. That would give them a boost!

I hope this is in jest.   Plants consume Co2 and release oxygen. 
Vertebrates (and invertebrates) consume oxygen and release Co2. 
Title: Re: More panels!
Post by: LowGear on February 22, 2018, 05:16:55 PM
What about the hours of darkness?
Title: Re: More panels!
Post by: dieselspanner on February 22, 2018, 08:09:53 PM
I'm not scared of the dark, I'm scared of the things that live in the dark..................

Stef
Title: Re: More panels!
Post by: LowGear on February 22, 2018, 11:01:00 PM
In olden days in hospitals when darkness fell they would remove flowers because after dark plants take up oxygen and output carbon dioxide.

Hey glort,  How come you just don't completely off grid?
Title: Re: More panels!
Post by: vdubnut62 on March 03, 2018, 02:14:17 AM
I'm not scared of the dark, I'm scared of the things that live in the dark..................

Stef

I think I am more afraid of what I'm afraid might be living in the dark that I'm afraid of.  ;D :o


No really, Glort would you mind terribly if I PM'ed you with some really stupid questions?
Ron
Title: Re: More panels!
Post by: BruceM on March 03, 2018, 04:04:29 AM
My power addition project is still slowly moving along.  With the additional 1500 watts, I decided my old linear PV current regulator needed a bit more power.  I did a redesign and nearly doubled the capacity, 7 instead of 4 power transistors.  I just got the new PCBs today.
It should easily handle up to 3000 watts, but when I checked on the big heatsink (12x10x1.3 inches) with a thermal model it just didn't have the guts for the 300 plus watts the new board can do.  So I ordered a new heatsink, 24x10.1x2.8", with about 4 times the capacity.  It's the downside of linear regulation- a $160 heatsink!  Could have stuck with the old one with a thermal disk controlled small fan but I wanted to keep it outside the power shed and small muffin fans and outdoors don't mix well.  Nothing to fail with a big hunk of finned aluminum, also.

I'll assemble the new PV current regulator board on the first good day for soldering outside.  Hopefully I didn't make any big goofs on the PCB layout. 

Title: Re: More panels!
Post by: BruceM on March 03, 2018, 04:12:35 AM
Hey Glort-  I was wondering if the Autopot valves are also spendy there in Sydney?  In the US the valve alone (for on pot or tray) is about $30 US.  The whole setups are also very spendy- $300 for a measly 6 pot setup with feeder tank.  Too steep for serious vegetable growing.

Title: Re: More panels!
Post by: BruceM on March 03, 2018, 04:48:30 PM
"I'm a big fan of forced air."

I ran a couple different free heat sink thermal models a few days ago before deciding what to do for the power upgrade and even the most pathetic, barely moving airflow TRIPLES a heatsink's capacity compared to still air convection/radiation.  I WILL be using a modest cooling fan for my low EMF inverter! 

Thanks for the info on Autopot in Au.  It's a great product but as you suggest, the same principle can be done in other ways. 


Title: Re: More panels!
Post by: BruceM on March 04, 2018, 02:16:53 AM
When the difference in temperature between the heatsink and the ambient starts getting small, then blowing more and more air (with an exponential increase in fan power consumption) will do less and less...that's the point you noticed experimentally where more air doesn't seem to help.

I got my new PV current regulator assembled and soldered today.  Now for a rough night with a whopping headache from the solder fumes.  I thought I dodged them but apparently not.


Title: Re: More panels!
Post by: BruceM on March 04, 2018, 04:47:16 AM
This new PV current regulator  is really a simpler version of the one I've had in service for the last 8 years or so.  It's just a big linear series regulator. It's set up now for 0-5V current as control (through an opto-isolator) = 0-16 amps output (limited by the max output of the PV arrays).  It uses seven 350V NPN Darlington power transistors (BU323) that are tough buggers designed for automotive ignition systems.  It is a "low side" regulator, the PV negative is below the 0V of the 120V battery bank. 

So it's really 3 different boards to do the charge regulation;
1. A Battery Regulator board; float, bulk and equalize, temp compensated 12V shunt regulator for each battery (10 total), with shunt current feedback.  This lets me charge a large series string but baby each battery individually; that means adding only a gallon of water to the set of 10 every 2nd year.  It's designed for AGMs, which I may use for my next battery set depending on prices at the time.

2. PV linear current regulator; just a linear series regulator for the 120V nominal array (120-220VDC).  0-5V in for 0-16 amps current.  The previous design did fixed net charge selections of 0.5 amps (float), 2.5 amps (absorption), and max (PV limited to about 5.5 amps).  The new BBC (see below) charges with a continuous adjustment of current as the batteries come up to full charge so will charge faster. Much faster with larger PV and AGM batteries; the cheap marine batteries I'm using now have moderate internal resistance and can't really absorb high charge currents as AGMs could.

3. Battery bank charge controller (BBC).  This is a 3 year old newer all analog (op amps) design.  that computes the real time minimum charge current to keep all the battery shunt regulators just barely regulating without exceeding the 3 amp shunt current limit and automatically transitions from bulk to absorption to float.  It does this smoothly despite fast shifts in load or PV charge (sun). It also does the equalize timing. 

Other projects in the works- updating my generator- DC charger to a fixed voltage  (150VDC) 10 amp design that feeds into the PV regulator.  The current design uses a homebuilt motorized variac and adjusts itself via PICaxe controller as the charge current tapers off.  Charging is so infrequent that I may simplify this and ignore the minor loss of fuel efficiency of regulating via the PV charge regulator.  I only charge about 2-3 hours per winter, total. With the new PV capacity that will lkely be zero.

Lastly, the newer (3 year old) analog battery bank controller board has room for expansion with an added embedded microcontroller.   I may add that to continue to be able to use my remote terminals (LCD plus buttons) in the shop and house to monitor and control.  I'd use this controller to for my low EMI inverter control and power management like pumping the well or pumping air when sun is available and demanded loads are low.   

I'll take some pictures of the new boards on my bench tomorrow.







 

Title: Re: More panels!
Post by: BruceM on March 04, 2018, 03:29:00 PM
I wish used panels were available here; I'd add one more set of 5 vertical panels for late in the day "sundown" power.  A set of 175's would be just dandy. 
Title: Re: More panels!
Post by: BruceM on March 04, 2018, 06:46:38 PM
Here's some photos of my new boards for my custom 120VDC off grid power system. 

The power regulation is all linear, both on the Battery Regulators, and the PV current Regulator. 

The new Battery Bank Controller is also all linear but has the option to add a shielded processsor module via filtered DB25 connector.  It uses Microchip 5v micropower op amps so it's all up power use is about 6 ma. The processor module will add another 5ma.  We're talking tiny, tiny power use.

The PV current regulator uses 7 parallel BU9323 Darlington power transistors.  So for my intended max of 16 amps at 146V (2336W), each would carry only 2.2 amps.  It will be mounted on the back of a large 24x10.1x2.8" finned aluminum heatsink on the outside wall of my power shed.  The heat losses during throttling of PV output is does not affect charge or direct use efficiency.

The Battery Regulators (one for each 12V battery) can shunt up to 3 amps of current but in practice, that never occurs for a well matched set of batteries.  Repeated cycling with individual battery regulation makes the batteries match very closely so the Battery Regulators tend to serve more as a very small correction for battery impedance matching. The battery regulators each have a external thermal sensor that is attached to it's battery negative post.

Definitely not the way things are normally done these days but phenominally low EMI and quite efficient.  Bulk charge losses are very low- diode drop plus 0.8V at 20A power.  Winter PV efficiency is down around 17% due to mismatch of panel array voltage (higher than necessary).  Size and cost of throttled (linear instead of rapid on/off switching) charging is certainly significant but that was lowest on my design priorities.

Sorry for the "soft focus" photos- I'm a shaky today but was too lazy to get out the tripod.



Title: Re: More panels!
Post by: BruceM on March 04, 2018, 06:55:37 PM
Here's a photo of my prototype system- some while still in test and development in 2009.  I'm still using the same boards now.  Time flies.

Title: Re: More panels!
Post by: carlb23 on March 05, 2018, 12:31:55 PM
Glort,

How many Kw of solar do you have now? 
Title: Re: More panels!
Post by: ajaffa1 on March 12, 2018, 11:45:54 PM
An interesting development, my neighbour is building a homemade off grid solar set up. He has been gathering second hand equipment for months. I have volunteered to assist in the hope of learning something useful.
It appears that he has got his hands on a couple of battery packs off forklift trucks, should provide good storage.
With his permission, I will try to post some photos and information once we get started.
Bob
Title: Re: More panels!
Post by: BruceM on March 13, 2018, 04:03:07 PM
I'm very skeptical about DIY internet claims for lithium battery banks that have no cell management.  Even minor corner cutting on series cell voltage management as the Nissan Leaf has done has resulted in many premature battery failures, and that's starting with new matched cells.  As you know, Tesla is no cutting edge, new tech company; electric cars are 100 years old and their car has no "new" technology other than fancy electronic displays and other ancillary computer features.  Instead they have been wise adopters and refiners of proven, existing technology. They use the Texas Instruments lithium cell voltage management IC's so that no series cells are left voltage-uncontrolled.  Reports are that they do have very reliable battery life because of this. 

Even 48V wet lead acid systems could have better battery life by incorporating individual battery management, but no one does because it would add cost and people are more interested in today's cost and not the expense of battery replacement.  In fact, just talking about battery replacement cost would be bad for business.
Title: Re: More panels!
Post by: ajaffa1 on March 14, 2018, 02:24:23 AM
Hey Bruce. when you say that individual battery management is not used because of cost, how complicated/expensive would it need to be to significantly improve life expectancy? Is this something that could easily be cobbled together out of cheap or second hand components?
Bob
Title: Re: More panels!
Post by: BruceM on March 14, 2018, 07:43:37 AM
This Aussie guy doing his own DIY powerwall is using full (parallel) cell level monitoring, as far as I can tell.  His presentation glossed over the technical details but those packs look like all series cells are monitored for over/undervoltage.  Alas, it appears his charging system isn't automatically balancing the cells since he's talking 2 days to equalize his cells.  That's NOT how cell management is supposed to work.  It should divert power from charged cells to the slower cells and thus keep them well matched on every charge cycle.  If his system can't do that, and is requiring regular extended equalization that's not so good. Since he's selling stuff, it may be hard to get an honest answer about service life of his cells/packs.

I would not touch lithium right now myself...I'll wait until the price beats lead acid for stationary applications where light weight is not important.   By then, you'll likely see cell management integrated into the packs and standards will emerge so that things are not so proprietary and expensive.  Hopefully other more enlightened nations will pick up the ball and run with it.  It's hard to imagine that racks of 1000's of tiny laptop batteries are really the best we can do...though obviously for now, it is.

I'm sure if you google around you can find more in the way of lithium cell management systems.  I'd have to look hard at the TI IC solution...I don't like dirtying up my power with a bunch of unshielded embedded processors scattered throughout the battery bank but given the fan out and total numbers involved, their bussed serial communications are ideal.  Many of the newer AVR and PIC processors have multiple I2C serial ports available to help with the fan out. 

It's not a trivial piece of engineering, but given the price of a few thousand lithium cells, it's obviously worth it.


Title: Re: More panels!
Post by: BruceM on March 14, 2018, 09:59:50 PM
How "modules" or "packs" are assembled regarding some combination of parallel and serial cells is relatively arbitrary.  You would prefer to see management at the module/pack level to cover every group of parallel cells. The bottom line is that cells don't all have identical internal resistance for charging and discharging plus those individual cell charge/discharge rates are affected by temperature and age.  Lithium cells are voltage devices so that 100 cells in parallel can be treated for charge/discharge management purposes as a single larger cell.  Overcharging cells reduces their life dramatically, as does dropping the voltage too low.  I don't recall the common cell failure modes but I expect some means of disconnecting and bypassing a module with some sort of failed cell(s) might be necessary in a car to allow you to limp home. Better to keep the cells from failing by good charge management but it's all a trade off for cost, complexity, and performance.

I expect that the most cost effective battery management system for cars will be found only after many years.  The high current charge/discharge cycles of EV use proved very challenging for AGM batteries too, and so various methods were tried until settling on management at the 6 or 12V battery (3 or 6 cells) level, since going lower wasn't practical.  I'm happy to sit back with my wet lead batteries and wait for the bleeding edge of new battery tech to mature and get affordable.

A true breakthrough in batteries would certainly be an industry changer.  Every crackpot thinks cold fusion or free energy schemes are real and suppressed, and that a magic carburetor once provided 150 mpg in a 8 cylinder pickup truck.  Everyone of these schemes I've looked at closely was at best a gross error in measurement, most are outright frauds or incompetence.  I'm not saying conspiracies don't exist, just that for the stuff I've looked into there was no need for one except in the minds of the promoters.  At one time I was reviewing and rating over 150 (per year) Internal R&D projects of big companies doing cost plus contracts (advanced development) with the Air Force.  (I was just one of many reviewers.)  After a while you get good at spotting technical baloney.   










Title: Re: More panels!
Post by: BruceM on March 15, 2018, 03:57:04 PM
There seems to be fine line between open mind and hard vacuum in humans.  Even in people very gifted in one area, such as Newton, they are often delusional in others (he was into mysticism and trying to turn base metals to gold).

We have such limited mental capacity that we must specialize, and that does make us very susceptible to being misled in areas outside of our area of expertise.  Many are incapable of any expertise.  So no surprise that even well meaning leaders in government (often lawyers or businessmen) will propose/fund/mismanage all sorts of programs.  Add that  many sociopaths are attracted to the power of elected positions, and you end up where we are today. 

Title: Re: More panels!
Post by: BruceM on April 11, 2018, 05:53:25 AM
No matter how you do it, working on a steep pitch is hard work.  My first home here in the White Mountains had 600 SF of solar hot air panels and duct work built into the south face of a custom trussed roof at 53 degrees of pitch.   I used two large ladders against the face of the roof.  One was an extension ladder we made a "hook" end for that hung over the peak, with the two sections screwed together. From ground level you went up a ladder than transferred to the roof ladder.  That way we could have one guy on each side of the 4 foot wide fiberglass glazing which was a bit over 13 foot long.  Two guys would be a must for 250 watt panels, if one of them was me. 

It's hell on the feet and legs to stand on a ladder that isn't near vertical. 
Title: Re: More panels!
Post by: BruceM on April 11, 2018, 06:07:20 PM
I've never washed my ground mounted PV panels,  but I do wash my solar hot water panels occasionally in the winter when they are working hard to keep up. 
Title: Re: More panels!
Post by: oldgoat on April 12, 2018, 02:23:03 PM
I thought the same as glort and goot on the roof and cleaned the dust and crap off my panels. Could have saved myself the trouble the increase wouldn't have even paid for the detergent I used.
Title: Re: More panels!
Post by: LowGear on April 15, 2018, 02:04:23 PM
I find the rat nests under the panels to be of greater concern than the grit on top.  We have more of a grit here than dust.  Our panels are at about 20 degrees.  That's about our latitude hence equinox gets us pretty close to perpendicular to the Sun.
Title: Re: More panels!
Post by: mike90045 on April 15, 2018, 03:26:45 PM
Quote
Still trying to figure out how to switch High voltage DC current so I can direct power the water heater. 

Are you inverting any of the power, or using all DC ?

The 2nd easiest way is to switch an inverter on / off and allow it to provide AC to the heater , 
otherwise, it's SSR's, snubbers, and heatsinks
Title: Re: More panels!
Post by: ajaffa1 on April 16, 2018, 01:32:47 PM
I`m not quite sure that I understand the problem, most PV/grid tied systems have a timer switch which feeds 240 volt electricity to the electric heater on your hot water cylinder. This timer is generally set to utilise the free solar power during the day with an override switch in case of failure or overuse. All of these systems have a thermostatic cut-out to prevent the cylinder reaching boiling point and exploding. If you really want unlimited shower/bathing facilities fit a larger, or secondary cylinder. If you want them to be totally solar powered use a liquid solar system with heating tubes on the roof and a small circulating pump.
Trying to feed 400 VDC through an immersion heater element sounds like a recipe for disaster, but maybe I have misunderstood what you are trying to do.

Bob
Title: Re: More panels!
Post by: BruceM on April 16, 2018, 05:42:23 PM
Warning!  Danger!

DO NOT use AC rated breakers or switches with DC over 24VDC.   I've tried that experiment with only a 500 watt load and fried a lot of heavy duty and commercial grade switches on the very first OFF.  Arcing and melt down is the result.  Putting a capacitor on the output won't solve the problem.  That can help with inductive kick back but that's not the only issue here.

I know you like to experiment and see things for yourself so make sure you use the 300V DC rated breakers to be able to reliably shut down.  Don't exceed that rating at the rated amperage.  DC arcing is dependent on both voltage and current; very light loads won't arc as much on opening the contacts.  As voltage and current go up, the arcing gets very strong.  In things like DC driven rail/subways, they actually use compressed air to blow out the arc.  In HV DC rated switches and relays, they use permanent magnets to bend the arc plus other methods to quickly move the contacts far and wide apart to extinguish the arc.

Unless you have found a Buck  converter (simplest of PWM) to regulate (lower) the output voltage, you must keep your string series voltage under load to match the rated heating element (RMS) voltage (or less).  Electro-mechanical relays for HV DC aren't commonly available.  If you don't want to so some component level soldering to add a opto-isolated gate driver IC to control a surplus IGBT module (cheap on Ebay) to do your own solid state relay, then you'll have to search for a solid state relay rated well above your operating voltage and current.  AC relays can't be used...they will arc and fry.

I use 120V nominal DC for my home, and the no load voltage of my PV array of 5 panels in series is 220 volts on so on cold days.  On cold days under load, the voltage is about 20V higher than needed for my 146 volt battery charging.  There is really that much swing in output voltage based on temperature.  Normally, your PWM/MPPT charge controller hides that variation from you, but for direct DC use, you have to think about things a lot more.

You must match the loaded PV string voltage to the load unless you can find a PWM/switching power supply to take a higher voltage and down regulate .   Most large switching power supplies with 230VAC rated input can be operated with 350VDC (Max- no load PV voltage) input.  It might be possible to find a large one or put two or more in series to get a useful DC output.
The issue will be the PV string no-load voltage exceeding the max input voltage...that will kill them fast.  Direct from PV well pump drives are designed to handle that big voltage range on input, so are another possibility.

I can make a schematic for the opto-gate driver (8 pin dip)/IGBT module method which would give you a SS relay that is bulletproof and can tolerate 500VDC.  But it is really the sort of thing for a electronics technician/hobbyist.

For direct DC drive, here's an example.  US water heater elements  are typically 4800 watts at 230VAC (same as 230VDC).  That gives us an element resistance of 11 ohms. 
At 200V it would be 3636 watts and 13.2 amps.
At 120V it would be 1309 watts and 10.9 amps

So as long as you keep the full load voltage of the PV string at or below the rated voltage of the heating element, you are right in that there is a wide range of useful heating being done on unregulated direct DC.  Brief moderate overdrive of the element won't fry it.  But remember to allow for the 20% boost in voltage of the PV on very cold winter days.  I would guess that you might be best off using one or two parallel strings of (9) 250 watt panels in series depending on how fast you wanted to heat the water. A single series string will be under 2000 watts actual.   Your no load voltage would be roughly 396 so a 600V IGBT module  is a good match. 

Please note that you cannot use the existing water heater  thermostat to switch the DC power directly, it must be done through your solid state relay.  The input to the opto isolator would be about 10 ma of 5-12V; that could be switched through the thermostat.

I use 120VDC for cooking and and other resistive heating appliances every day, and operate all my computer gear on it as well.   I use HV mosfets for switching loads in cooking appliances, using the built in thermostats to only control the mosfet(s).  For simple things without an active switching thermostat such as crock pots, no modification is  needed.  Voltage regulation of the DC isn't really needed since power co. AC was never well regulated either. 

I hope this helps.  I was not impressed with the prices of large switching power supplies, though I did look into that.  For myself, I'd go direct PV to IGBT module approach.  With some 4000 series CMOS logic and a second IGBT module, you could automatically switch the PV array low side back to an inverter when the water tank temperature was maxed out.  I can help with that as well, again, just one 16 pin dip IC will do it.














Title: Re: More panels!
Post by: BruceM on April 16, 2018, 05:52:28 PM
PS, a DIY solid state relay ala opto gate driver and IGBT module is pretty simple.  A buck converter (PWM) is not something I would recommend you should try to tackle as a first electronics project. Frying the $50 IGBT module is the likely result, and an o-scope would be essential.  The same IGBT module could be used for either.
Title: Re: More panels!
Post by: ajaffa1 on April 16, 2018, 11:30:11 PM
Hey Glort, Bruce is absolutely right about dc relays being dangerous, don`t do it!
My suggestion is to use a standard grid tie inverter. These only produce power when there is a 240 volt 50Hz supply connected to them, they produce nothing when there is a power cut. If you put your timer and the water heater thermostat between the grid and the invertor it will only produce electricity when there is a demand for hot water. Carefully matching the size of the invertor to the heater element should alleviate your issue with back feeding the grid.
Title: Re: More panels!
Post by: BruceM on April 17, 2018, 01:44:06 AM
Great solution. Bob, ingenious!

What are your Aussie water heaters like, Glort?  Do you just one element or two, with essentially two thermostats, as we do here in the US?  Ours have the upper element on for fast recovery when tank gets too cold, the lower element is switched on when the tank is just a little cold.  Elements are each 4800 watt and mutually exclusive-  never both on.  Both elements are controlled by one "thermostat" module. 




Title: Re: More panels!
Post by: BruceM on April 17, 2018, 06:30:40 AM
Bob's GTI approach of only applying the AC to the inverter through the water heater thermostat switch seems to meet your goal of not backfeeding on that meter/circuit, if you limited the PV array to less power than the water heater element could handle.
With a double pole, double throw relay the inverter outout could also be directed elsewhere when the water heater was hot, this by simply having the coil of the DPDT relay fed by the WH thermostat,  if that is to be the highest priority.

I can imagine how after the luxury of bargain priced but working GTI's and a wide range of PV voltage, the details of direct DC seem harder.   

The range of heater element wattages does make it easier.  Your dual element units are exactly the same as the commonl US models.  Having two elements for two different sources could be quite handy.


Title: Re: More panels!
Post by: ajaffa1 on April 17, 2018, 09:48:41 AM
Hey Bruce, love your idea of DPDT relay to divert power elsewhere when the thermostat on the HW system opens. Perhaps Glort should buy some of those storage heaters and redirect current to them, this would give him unlimited solar hot water and heating at night with no fear of back feeding the grid. Adding an electric AGA to the system would be costly but also give him free cooking facilities (they are basically a glorified storage heater). Hope his wife doesn`t ever see this post or an Aga because she will want one and they are really expensive, there are probably cheaper alternatives available.

Bob
Title: Re: More panels!
Post by: ajaffa1 on April 17, 2018, 12:33:08 PM
Hey glort if you are considering and Aga or similar unit, try to find one that runs on heating oil. They have a gravity fed wick burner that will run real good on WVO, hell of a lot easier and cheaper than an electric version.

Just a thought, if you have spare electricity after heating your hot water, what about a hot tub? I`ve been lucky enough to have sat in one in the Swiss Alps in minus 30 degree temperatures after a long day of skiing. Very good for reviving parts that other beers can`t reach.

Bob
Title: Re: More panels!
Post by: BruceM on April 17, 2018, 05:11:44 PM
Snubbers are simply a resistor and small capacitor with values selected to suppress the oscillations (aka ringing) from switching or the EMI emitted when diodes start and stop conduction.  There is a method to determine the values for optimum snubbing by trying different capacitor values while watching the ringing on the oscilloscope. A 50% reduction then lets the engineer calculate the optimal values.  This is only a modest reduction in the ringing or EMI, and if you use your trusty AM radio near any wire connected to your GTI, you will see that there is a whole lot still left.  The values used for this are small,  and excess capacitance just causes power loss in that the power transistors must overcome the capacitance when switching on. Values of 0.001 to 0.1 uF and R values of 1-100 ohms would be ballpark ranges.

For simple on-off controls that aren't pulsing rapidly as in a PWM controller (say at 50,000 times per second) they are often not used at all. 

When turning off an inductive load, there is also an inductive kick back which can cause some issues- if the low side (negative) is being switched, when the load is off, the voltage goes high.  It can be more than the switching transistor(s) are rated for.  Here a small capacitor can absorb some of that spike and keep the voltage within safe limits.  Selecting the transistors with voltage rating of near double the actual use will often provide margin to be able to ignore "snubbing".  The value for the cap is small- 0.01 to 1.0 uF.  AC or DC are handled differently, and there are several techniques commonly used for DC relay coils, a notorious inductive spike generator when switched off due to the very high inductance.  The techniques may include both a diode and snubber.  If the switching is infrequent, and the voltage rating of the transistors is high enough, no snubbing is needed. 

Slower switching, with limited slew rate also reduces this inductive spike problem and this is the technique I use for switching DC electric cooking elements along with picking transistors with a fair amount of head room- typically 250 volt rating for switching 120-140VDC.  I use no snubbing and limit the power transistor on/off times via high value resistor to gate...this can only be done when using MOSFETs rated for semi-linear operation.

AC relays, switches and breakers on DC typically fail on opening. DC rated relay contacts must be way tougher, they must open faster and further. Bouncing of contacts is normal so each open or close is actually a series of events...and even closing causes arcing.  DC also means that metal will always be transferred in one direction between contacts, which is very hard on the contact life.  Adding capacitance will  increase the current on closing of contacts but will reduce it on opening.  Arcing on opening will be helped by capactance since the difference in voltage seen at the contacts at opening will be smaller, and the current across the open contacts will be reduced somewhat.  So capacitance can improve things.  But I would not normally use AC relays, switches and breakers in and around the home on high voltage DC.  They WILL fail.

Even my 150VDC rated wall light switches fail over time.  Lights with regular daily use of say 10 times a day will start to fail (sound of arcing on switching) in about 5 years.  The old design rotary lamp switches also start to fail on DC in time, the ones most often used, again in about 3-5 years.  I have metal electrical boxes and all wiring in metal conduit, so there is no risk of fire.  The solid state switches (HV mosfet) in my cooking appliances have never failed...solid state switches are the way to go for DC.

DC mechanical switching is very different from AC; AC has spoiled us because the interruption of current flow every 8 or 10 milliseconds (for 60Hz or 50 Hz power) means arcs stop almost immediately, so all mechanical electrical contacts have a much easier and longer life. They are "value engineered" to just work well enough for AC.  The exception is rotary lamp switches which are still the same as the original DC version.  I also did find one double pole switch that has worked well for 120VDC at up to 3 amps ...but it is no longer in production, and I blew over $200 on testing others to find not one that would work.

"What I was wondering was if having a constant small load would help with the arcing?
My idea which I'm sure is way too simple to have legs, was to have something like a pair of 25W globes in series ( for voltage handling) across the switched terminals of the relay so effectively there was power to the heater element all the time.... Just very limited and inconsequential.
If the circuit was not completely dead, would that give the power a path to follow and reduce/ eliminate the arcing when the relay switched?"


The parallel small load would reduce switching current and voltage only very slightly. Not enough to allow use of AC relays and breakers.  Some AC breakers are said to work for 12/24V DC, but since the breakers sold by Midnight Solar are DC rated and approved (150 and 300V versions), it seems foolish to tempt fate.  Even with breakers, it is recommended that  for an off grid system, a DC rated fuse of high rated current be used between battery and breakers since a sudden dead short could cause instantaneous currents so high (before the breakers can open) that the breakers contacts will weld closed.

DC is much better (4x) than AC for shock safety, but greater caution needs to be taken regarding mechanical switching contacts.

"If I put a lamp between the AC side of the inverter and the supply, would that allow the  inverter to sync with the grid and stay connected?"

 Alas, no.  The inverter will immediately see an overvoltage when it tries to feed the circuit due to the resistance of the lamp.  Same as if you used a long run of tiny wire between the GTI and power panel.




Title: Re: More panels!
Post by: merkland on April 17, 2018, 06:24:20 PM
Hey glort if you are considering and Aga or similar unit, try to find one that runs on heating oil. They have a gravity fed wick burner that will run real good on WVO, hell of a lot easier and cheaper than an electric version.

ajaffa1
Are you speaking from experience? I have had an oil(Kerosene) Aga for some 47 years and, knowing how fussy and temperamental they can be over the fuel they will use, I am extremely dubious of them being able to use wvo as a fuel. The wick burner they use is entirely dependent on the fuel readily vapourising.

merkland.
Title: Re: More panels!
Post by: BruceM on April 18, 2018, 03:01:41 AM
Alas, double pole switches (AC commercial grade ones which I tested on 120VDC) have the same problem on DC. I only found one out of about 6 or so that worked, and only at current below 3 amps at 140 VDC.  I hord them for special project needs since that model is no longer in production.  Ditto for my Cooper brand 150VDC rated wall switches (a duplex switch).

High voltage DC relays do exist.  Here's a german company that makes them starting at $132. each.
https://www.spselectronic.com/us/products/details-us/relay-rl-42-l-1/
There may be better suited ones out there.  The problem is that once you leave standard, high volume products, prices soar. 

The issue with higher voltage DC at currents in the 10-20 amp range cannot be solved by trickery and using a $3 AC relay to the best of my knowledge.  You can buy a suitable solid state relay for $200 at Digikey, or make one for about $20 in parts; an opto isolated gate driver and a few 600V IGBT transistors in parallel plus the smallest (<50 ma) 12VDC power supply. 

What you CAN do with cheap AC mechanical relays is provide zero current switching of DC; you can redirect from one load to another with the current off.  Just do it in steel enclosures so that no matter the failure there won't be a fire.

It might be useful for you to play with some switching at roughly 230VDC from some panels using resistive heaters or heat lamp loads to see what DC arcing is really like.  Just get one Midnight Solar DC rated breaker to use for a reliable kill switch.  US AC outlet plugs and sockets were originally designed for DC, and can also be used for a kill switch...just use a high current one and don't pull the plug out slowly! The contacts were designed to be "self cleaning" with a good wiping contact surface.  I don't know how your plugs/recepticals in Australia are designed.







Title: Re: More panels!
Post by: ajaffa1 on April 18, 2018, 12:06:18 PM
Hey Merkland, yes I speak from experience. In the early 1990s I was married with three daughters, all horse mad. I was talked/bullied into buying a farm for their hobby. The four bedroom property in Herefordshire England came with an oil fired Aga, for cooking/hot water and solid fuel heating Coal/wood for everything else.

I set about modernising the property, I installed a new oil fired central heating boiler feeding heating radiators in each room and the old Aga was dismantled and sent away for restoration. The new kitchen I built and fitted had an electric fan oven and an LPG cooktop, The plan being to only use the now reinstalled Aga in the winter months.

That year we had a very cold winter and surprise/surprise the cost of heating oil went through the roof. To add insult to injury the government also decided to start taxing heating oil driving the costs even higher.

I experimented with a lot of cheaper fuels including WVO. Basically these vaporising burners are little more than a glorified candle and they will burn just about any hydrocarbon (I never tried animal fat) The tray at the bottom contains the hydrocarbon which then flows up the concentric wicks where it burns. The heat generated heats the tray full of fuel to the point at which the hydrocarbon fuel in it starts to vaporise (imagine a deep fat fryer on fire). The temperature control is achieved by increasing/decreasing the level of oil in the burner tray. There is an electric thermostatically controlled float chamber normally mounted on the left hand side of the Aga which controls the level of the fuel. If I remember correctly the static/unlit level in the tray is supposed to be around 6mm of fuel and can be adjusted/levelled by winding the mounting bolts up or down. The control unit has adjustment screws which allow you to determine the maximum and minimum rate of burn. It is imperative that once lit and hot these adjustments are made to ensure a clean burn. A clear blue flame on the top of the vaporiser on maximum and a clear blue flame inside the vaporiser on minimum.

I had a lot of problems with this and found that a smoky flame would quickly cause clogging in the flue pipe. Experimentation and constant vigilance overcame these problems. I also found some fuels difficult to light, a mixed air and propane gas blowlamp sorted the problem.

I eventually converted everything to run on red diesel because as a farmer it was the cheapest and tax deductible. Bob one/ government nil.

For those of you who have no idea what red diesel is it is a tax exempt fuel for farmers, industry and construction machinery, it`s also used by the military. If you get caught using it on the roads expect a very large fine, repeat offenders go to jail. The military also use a red petroleum. These fuels contain a dye which stains the inside of fuel systems and is easily identified by government inspectors during routine road side inspections.

Strangely enough my experiment with farming worked out very well. At the time the British government and the technocrats that run the EEC had the common agriculture policy in place. This was a system of subsidies which assisted farmers in producing foods that were in short supply. No surprise then that we ended up with beef and butter mountains, lakes of wine all being stored at huge expense to prevent a fall in wholesale price.

Rather than reduce or redirect the subsidies, which could have adversely effected farm revenues and votes, the gubermints decided to introduce the set aside scheme where they paid farmers not to produce anything. We were expected to maintain our properties and destroy weeds but grow nothing.

60,000 dollars a year to not farm is the sweetest deal I have ever had! I also received government grants to plant trees and hedges. All capital expenditure was tax deductible as were machinery/fuel purchases and the costs of any outside contractors. Bob two/government nil.

At the time I also ran a construction business and the cost of machinery hire became negligible as I simply purchased the equipment through the farm and claimed it back as tax deductible expenditure. Bob three/government nil

I probably drove my accountant to a near nervous breakdown but there is a huge difference between tax avoidance and tax evasion. No farmer that I ever met ever paid the government a cent in tax on any profit they made, It was all redirected back into their business. A call from the accountant and we would run down to the local agricultural supplier to by a new tractor, even if we didn`t need it.

Bob 
Title: Re: More panels!
Post by: BruceM on April 18, 2018, 05:19:16 PM
"I was thinking today I might put a meter in the kettle as well. I try to limit myself to about 10 Coffees a day and I'm wondering how much power that adds up to. I'm thinking it's going to be a surprising amount. Mrs has a habit of filling the kettle every time she boils it and I cannot get through to her to only boil enough for the cup she wants, not fill the bastard with 3L of water. "


My off grid 120VDC home/lead acid battery bank was powered by just 875 watts of panels until recently.  On sunny days I do mostly electric cooking, and very quickly I learned that excess water heating is your energy enemy. For tea, I use a 300 watt immersion heater.  Works fast and efficiently, even faster if I start with 130F solar heated hot water.  For cooking, I have crock pots and a small modified 600W toaster oven, and a 500 watt hot plate.

My favorite for general DC cooking is a modified  Aroma brand 300 watt rice cooker. I added a mechanical timer and changed the wiring so that the magnetic scorch switch on the bottom of the stainless cooking pot turns it off.  (The magnet looses strength and releases from the bottom of the pot if it gets hot, which opens a switch.) A single 250V MOSFET and resistors do the power switching, the timer and magnetic scorch switch control the MOSFET. This rice cooker is my favorite, as I can add just barely enough water in the bottom (1/2 cup) to cook/steam.   It also has a steamer pot that sits above the 6 cup pot.  I have serious short term memory problems and the biggest plus for me is that I can never burn up a meal with it, and even if I go out to the yard or shop and forget, when I come back there will be something edible and not a mess.

I've also learned that there is a good 10 minutes worth of slow cooking for free after the power times out. For a bachelor meal the timer is set for 25 minutes and food is ready in 30 minutes.  Just under 1/2 cup of water in the 6 cup cooking pot is sufficient.

300w x 25 minutes= 125 watt-hrs  or about 1 amp hour at 120VDC  for a meal.  My battery bank is 110 AH at modest current draw so both early breakfast and evening meal on battery power is not a problem.  I use the gas range on dark days and for most baking and cooking for groups.

It really doesn't take much electrical power to live on very comfortably if you are heating with solar hot water space heating and have no need for air conditioning due to super insulation with enough thermal mass and cool night time temperatures despite 100F days.







Title: Re: More panels!
Post by: BruceM on April 18, 2018, 11:21:20 PM
Thanks, Glort.  Now that I am no longer able to help disabled individuals with their homebuilding issues as I did for many years,  I would like to try and leave some sort of "leg up" for others so they don't have to learn it all the painfully hard way as I did.  Most people with seriously disabling MCS and/or ES have a unique pattern of brain damage (clearly visible on SPECT and FMRI) and have a hard time learning and visualizing complex things, so I think video clips with a more "hands on" demonstration might be more effective, though some sadly have no computer access at all. 

Truth is my writing skills are not great, besides being very mentally challenging for me.  I don't know how to write for non-engineers.  Over 20 years ago I wrote a 16 page condensed article on home EMF mitigation for a friend of a friend's book. (University professor writing about coping severe MCS disability.) She found it too complex, she had hoped it could be like a cookie recipe!  Some years later I was contacted by a newly disabled electrically sensitive guy (Phd in Biophysics who worked at Los Alamos). I sent him the article and worked with him via phone for first home and car EMF mitigation. He was able to improve his home situation by 90% and got back some health and is able to do some contract research work now, though he can't work full time in a typical office anymore.  A few years ago he wrote me to tell me how every time he reads the article, he has learned more and can apply more of what I wrote. 

This was intended as a compliment, but since I had attempted to write the article for lay people, I was pretty discouraged. 

I have attempted to find a co-author to help humanize my writing but so far they lacked enough technical savvy and so could contribute little more than correcting grammar and spelling.

I do have a digital camera that does video and sound that is exceptionally low in emissions and I can tolerate it for short periods.  I made 3 short videos about my prototype ultra low EMF inverter design for a civil engineer who has moderate ES and was interested in how it was even possible to have an inverter be low EMF.

I now have upgraded my rear projection workstation to a WXGA (1280x 800) projector over the last couple months; I had to add an external IR remote controlled focus adjustment since the Qume Q5 optics aren't temperature stable.  My old SVGA - LED pocket projector in a shielded enclosure would not allow me to use any video editing software at all- they are all designed for XGA as the minimum display.

I would much appreciate any advice and/or assistance in getting me going in a fruitful direction. I'll PM you with my email address.

 






Title: Re: More panels!
Post by: BruceM on April 19, 2018, 06:09:53 PM
"Amps from elbows" pretty much nails the problem. 

I'm not sure how tackle that problem.







Title: Re: More panels!
Post by: LowGear on April 20, 2018, 08:24:48 PM
Panel Price Alert:

I saw previously installed 250 Watt panels in the local craigslist (Big Island Hawaii) for $100 each.  I phoned and found the seller had eight inquiries in the first hour.  Not the screaming deals glort reports from Australia but still pretty darn good.
Title: Re: More panels!
Post by: BruceM on April 20, 2018, 09:39:39 PM
sunelec.com often has panels at 0.50 to 0.60/watt.  Decent outfit.
solarblvd.com used to be the bargain king but they seem to have fallen on hard times lately. 

Title: Re: More panels!
Post by: BruceM on May 20, 2018, 04:12:10 PM
13KW per phase is brutal.  Heat pump for heating when outside temps are 0C is a joke; most systems are on resistance heating at that point as I suspect yours was.  The duct losses are huge; often R1 insulation on leaky attic ducts above the insulated envelope.  It's as if most homes where designed by the power co. to maximize their profits, as well as the HVAC guy to sell the largest, most expensive unit, instead of designing the house to minimize energy use.  It's as if insulation was very expensive, and had to be maintained and replaced, so we must use as little as possible.

I think you're on the right track with night time zoned resistive heating.  Checking heaters with an ELF magnetic field meter and the AM radio will show you that the best heaters can be 100x lower.  The lowest EMF are typically the oil or water filled radiator type, or electric-hydronic baseboard types.  They have the smallest current loop area with a small element.  If they use diodes to create a low wattage, that screws the deal and you get lots of diode generated EMI since they didn't bother with snubber EMI supression.


 

 
Title: Re: More panels!
Post by: mike90045 on May 31, 2018, 06:16:51 AM
AC Heaters ?   Does your air conditioning use thermal coils for heating, or a heat pump?   Simple resistance heating has been surpassed by heat pumps, easier to move heat, then to create it.
Title: Re: More panels!
Post by: BruceM on May 31, 2018, 07:35:31 AM
Most air heat pumps get piss poor efficiency below 40F.  They promise the world but I've not seen one yet that is worth a hoot here at 5600 feet elevation.  A friend got conned- and what he really got was resistive heat strip heating with forced air (the highest cost heating on the planet) all through the typical 15F winter nights and colder days. His electricity bills were hideous.

In the Phoenix Metro area, air exchange heat pumps worked great for our minimal winter heating needs.  It was very rare that the resistive heat strips ever kicked in.

For Canadian style winter heating needs, ground source heat pumps are king.

 https://dandelionenergy.com/
Title: Re: More panels!
Post by: ajaffa1 on May 31, 2018, 10:39:35 AM
Hey BruceM, I`m interested in your experience of sensitivity to EMF. Recently a Telco build a telecom tower overlooking my property(approximately 400m and in direct line of sight). Since it went operational I have suffered depression and fatigue. Today my wife drove to town and reports that she does not remember the journey and had no idea as to why she had driven to town. We have also recently lost several of our chickens to cancer. Could these symptoms associated to the tower?

Bob
Title: Re: More panels!
Post by: BruceM on May 31, 2018, 06:29:07 PM
Bob, your response to the new tower is well within the types of changes that others have noticed.  All radio emissions have the effect of being a stressor,  which the US VA researchers Becker, MD and Marino reported in the early 1970s.  On military bases getting new high power, high frequency transmitters, residents of base housing showed elevated cortisol levels and other markers of stress.  Of course the military and telecom response to this was predictable.  Marino at LSU, ran the definative study proving that Electrical Sensitivity is real, physiological, and that effects of EMFs can further be detected via special QEEG even in those not consciously aware of it; other studies have shown profound brain effects from brief cell phone use, but there is big money in cellular communications. 

Those with brain inflammation from autoimmune, toxics, or head injury are often accutely aware of effects. Recent evaluations of those self reporting electrical sensitivity consistently show via FMRI and SPECT scans  brain damage much like that of a closed head injury. 

Your own home wiring and wireless use is also often a contributor, so I encourage those without OCD or panic disorders to get the appropriate meters and see if major improvements can be made there.  Often, the new cell tower is just the tipping point, and the underlying culprit is the EMI radiating 24/7 from the home wiring, as well as magnetic fields from wiring and grounding problems.  Both are readily correctable with some time and effort but very little expense.

Shielding of the home or at least portions of the home is possible but is much more of a technical project and expense. If done well it can have the effect of moving you 5 miles or more away from the tower.  Avoid the use of expensive shielding materials such as conductive paints, and instead use things like breathable foil barriers, wire mesh, or aluminum foil.  Many people have been fleeced and spent tens of thousands and accomplished such a small improvement as to be unnoticeable.  My own home was built as an experiment to see what could be accomplished re: shielding of a home on a small budget.  The house has been tested and provides -110 dB of shielding at 2.4Ghz. This is limited by the leaky front door, and would otherwise be 120dB.  I have "overscreens" of 47 thread per inch stainless steel wire mesh over all my windows.  Materials plus labor for the shelding added only about $10K to the cost, as I was already planning on using a foil laminate system over drywall which I had developed for those with severe chemical sensitivity.

I can send you an article I wrote over 20 years ago on practical, hands on home mitigation if you'll send me PM with your email address.  I'm happy to help those who are willing to take the bull by the horns, learn and do for themselves. For many, the whole notion of unseen forces (radio waves, radiated EMI, magetic fields) is so disturbing that they are afraid to do anything or lapse into denial.  (I was in the latter group myself.)

For normal folks without severe electrical sensitivity, Cornet makes a single combined broadband RF, ELF magnetic and E-field meter (ED-88T) which is adequate along with an AM radio- the old Radio Shack 12-467 or Sony ICF-S10MK2.  Learning to use the AM radio as a poor man's near field sniffer for detecting and locating home wiring EMI is especially important; in less than an hour you can both find and identify offending sources in the home by simply holding the AM radio as you switch off circuit breakers at the main panel.  Often the fix is as simple as unplugging something unless in use; for example I have found many electrical stoves have such unbelievably bad quality switching power supplies that the entire home wiring is radiating and can be heard via AM radio within 6 of any wires in the wall, ceilings, and floors. Adding a switch to turn off this portion needed only for the oven solves the problem, as the burners do not require it to be on at all. It only needs to be on for oven use.

I am very glad to help those who are trying to learn about this, and reduce the unnecessary health stress of their home electrical system on themselves and family members.  It is the cheapest health insurance you can ever buy.  Most problems are readily correctable!!!

Specifically for depression, I'd suspect that endocrine disruption is happening- your autonomic system is being affected.  Besides fixing the home situation to dramatically lower your daily EMF exposure, I'd suggest getting free T3 and reverse T2 thyroid tests done, as well as 4x a day saliva cortisol levels, and for men, testosterone.  These are all things that can profoundly affect cognition, energy, depression and/or anxiety, and are again are something that can be corrected via supplements and/or hormone replacement.  Correcting the thyroid and cortisol problem can restore you dramatically. 

Assessing the home situation via meter is always the starting point.  Without any meter, step one is to make sure the head of your bed isn't on the same wall as a power meter, and that you don't have wireless on in the home at night, and you don't have a plug powered clock/radio on your bedside table.  Meters are critical- you can't know what needs doing or if you've got it corrected without measurement.

Best Wishes,
Bruce

PS-  Your distance from the tower is alarming and depending on the antennae orientation you could be in a very high level situation.  If it has only just been installed in the last week, you may find that the accute symptoms will subside IF you and your wife are still sleeping OK.  If it has been months, uh oh.  Depression is a very serious thing, and as Glort suggested, taking a holiday from the home might be very helpful in sorting things out.  But please get a meter, as often unseen WIFI transmitters can cause microwave levels higher than the tower! For those who have developed severe electrical sensitivity, getting away from EMFs can be a serious difficulty.





 
Title: Re: More panels!
Post by: ajaffa1 on May 31, 2018, 11:42:49 PM
Thanks BruceM for your detailed reply. I have a mate who is an electrician and has access to an EMF meter, I`ll get him round asap. The tower went live about three months ago and I have had nothing but mental health issues since. My GP put me on an antidepressant called Sertraline, about 1 in 10,000 have an adverse reaction to this drug, guess what, I was the one. Ended up in hospital with blood pressure of 205 over 105, the ambulance cost me $800! The trouble is that Sertraline is extremely addictive so you can`t just stop taking it because of the side effects. I`ve been lowering the dose for weeks and am now free of it. Got to go back to the GP next week to try and find an antidepressant that isn`t going to kill me.

I think the attached photo should give you an idea of the view of the tower from my veranda.

Hey Glort, yes I have very nice .223 with telescopic sights. I have considered a little target practice but think the authorities would take a dim view of my blasting away at their critical infrastructure. This tower is a high power relay station, where it is it attracts a lot of  lightening strikes, I have considered going up there and disconnecting the lightening conductor/earth wire. First strike should fry all the electronics.

Bob
Title: Re: More panels!
Post by: BruceM on June 01, 2018, 01:13:24 AM
Bob, alas most electricians know nothing about EMFs except that they fully believe in the "religious training" (supported by shoddy power company cigarette science) they have had that there is no problem.  Electricians have no real technical training whatsoever in my state; they learn the rules by rote and by putting in their years under supervision but they are ill equiped to deal with technical issues outside their rules because they typically lack any technical background. Even a HS diploma is not required in my state.

In particular, I have NEVER helped with a home EMF mitigation project where we did NOT find serious high frequency EMI on the home power, radiating from all the home wiring.  Usually that is from the homeowner's own equipment.  Sometimes it is due to poorly maintained distribution lines, with arcing on loose and/or corroded metal hardware on the pole near the lines.  These can be readily located via AM radio and Air Band radio. I helped with a home of a woman with a very rapidly progressing case of Parkinson's a few years ago.  Ended up that two bad arcing sources within 2 miles were the culpret.  She had no AM radio reception in the house- the entire AM band was making a 120Hz buzz anywhere in the home and along the wiring coming into the home when home power was turned off (the tip off that it's an external source).  I had my helper walk the lines with my radio gear and he found both sources per Marv Loftness's approach in just an hours walking.  With the pole numbers marked down and poles marked with red tape wrap, the power co. was very cooperative. 

Whether this is someone's "big health issue" or is just another mild stressor is impossible to predict.  But there is no harm in correcting what are mostly simple EMI and code violations of wiring and some grounding issues.  You can't really tell by looking, the most innocent looking situations can be a horror show, and vice-versa.

It's hard for me to understand the necessity for wireless in the home. Pulling Cat6 cable is not a big deal and with a jack at each person's favorite working locations you're covered.  The idea that you must be connected at all times and in all places is telecom marketing hype for suckers.  The evidence is increasingly pointing to this as being NOT at all helpful for young people, who have a much greater incidence of all kinds of metal health and chronic health issues.




Title: Re: More panels!
Post by: ajaffa1 on June 01, 2018, 01:24:02 AM
Very good advice about staying away from these towers. I remember a group called Fathers for Justice in the UK, they protested against injustices in the divorce courts. One group climbed one of these towers to put up a banner, unfortunately they were unaware of the dangers and can no longer father anymore children.

Bob
Title: Re: More panels!
Post by: ajaffa1 on June 01, 2018, 01:37:33 AM
Hey BruceM, fortunately for me the local electrician is very knowledgeable and a campaigner against all kinds of pollution. They have recently put up another of these towers in the middle of the local village where he and his wife live. I`ll take a photo when I go to the market on Sunday.

I have purchased all  the new switch gear I need to redo the main distribution board on the house and I have already fitted two new earthing stakes. The energy company renewed the incoming overhead cable only last year.

I`ll check out Merv Loftness and work out what needs to be done to reduce the risks.

Bob
Title: Re: More panels!
Post by: BruceM on June 01, 2018, 02:05:37 AM
 Marv Loftness wrote a book about power line EMI and how to locate and correct it.  He was a wonderful man and helped me greatly.  The ARRL also has articles on locating power line arcing. 
http://www.arrl.org/power-line-noise

The arcing happens at power voltage peaks, when current is strongest so induced voltages in hardware near the lines are greatest.  There's a spark and the resulting broad spectrum burst at 120 or 60 Hz.  Older/poor tuner AM radios are best for detecting this, as the 120 hz buzz is distinct and characteristic. A tuner which has static (white) noise between stations is what you want.  Because it's broad spectrum, the frequencies fall off with distance, so while detectable in the standard AM radio band up to 2 miles away, the Air Band AM radio will only pick up the source if you are within a few poles, typically.  I modified an Air Band radio to add an external cut down UHF yagi, with shielding of the radio. It can reliably and quickly locate the specific pole.  Spectrum analyzers DONT WORK for locating this type of low frequency pulsed broadband source, because of the way their swept tuning system works.

Someone could make a good living finding power line sources by using these simple tools and a modified MB300D like mine for the search vehicle.  I can put a whip Air Band antenna on my roof and drive the power line, since my alternator is disconnected and so are all other car sources of EMI.  Alas, I get a very bad MS flare up and headache/depression from spending time along power lines. (Or in typical home EMF levels.)



Title: Re: More panels!
Post by: BruceM on June 01, 2018, 05:18:32 AM
To have a totally clean DC harness on the 1985 and earlier MB diesel sedans, I disconnect radio, motorized antenna control, environmental control unit, tachometer, cruise control and crankshaft TDC sensor.  The solenoids are clean resistive DC loads unless there is a dirty connector with arcing which shits the bed.  I've done some rewiring and plumbing changes to get my down the road DC load to 1 amp. (The stock 85 300D has a 2 amp solenoid energized all the time to NOT have heat.) The aftermarket alternator I modified for a filtered output and NOT using the alternator body as ground has no measurable stray field when off, though the MB stock one did. 

I use a PV panel in roof with my own linear charge regulator.  I can't drive at night anyway. A former Los Alamos physicist friend with ES converted his 1984 MB 300D headlights to LEDs w/ linear regulator, and added second larger battery in the trunk so he can drive for a quite a few hours at night now.  He does contract research now, as he can't be in a typical office (WIFI, etc) all day.



Title: Re: More panels!
Post by: ajaffa1 on June 01, 2018, 08:53:55 AM
Thanks BruceM for the link, that`s quite a lot of information to assimilate in one go. Being a bear of little brain, it could take me a while to digest it all. Then there is the issue of trying to implement/apply what I have learned. I think this is going to be one long weekend, especially with having to adjust frequencies from 60 Hz in the US to 50 Hz in Australia and the associated radio interference. I like a challenge, I`ll let you know how I go and no doubt ask a sh1t load more questions.

Bob
Title: Re: More panels!
Post by: ajaffa1 on June 01, 2018, 09:03:15 AM
Further to my previous post, I had a friend who lived in the Soviet Union before it`s collapse. He was being paid a western salary while there so he lived like a king. He decided to have his apartment redecorated, he was very surprised to find that wall paper came with it`s own built in Faraday cage to prevent the Stasi from bugging your home. I wonder if anyone is still selling such a product.

Bob
Title: Re: More panels!
Post by: BruceM on June 01, 2018, 04:54:05 PM
Yes, there are many specialty shielding products, however, none will perform as well as good old aluminum foil.  Aluminum foil can be applied to smooth painted drywall with cornstarch paste rolled on the wall, the aluminum unrolled down the wall, and pressed down with a plastic wallpaper smoothing blade to squeegee out the excess cornstarch. Faster than wallpapering and cheaper.  The seams are foil taped.  When there are no gaps, good old household foil will provide better than -90 dBm of shielding. (Decibels of milliwatts of transmitted power.) A typical 5 bar (full signal strength)  cellular situation is -50 dBm of power.  A typical building with WIFI will be -30 dBm.  0dBm (1 milliwatt) is utterly insane, from my perspective, and is only present in close proximity to transmitters. Bob's situation is likely in the 0 dBm range.  In close proximity to transmitters it will go to the +dBm range (over 1 milliwatt).  I prefer to work and can only think in dBm because a huge range of power can be intelligibly represented with 2 digits and a sign.  I have a chart for conversions to/from other units.

Shielding is almost entirely limited by cracks and gaps in the shield; windows, doors, etc. No point in sheilding a wall if there will be big cracks and gaps. You are unlikely to get more than -7dBm of shielding by metalizing a single wall facing the source, and that is often not enough shielding to be worth the effort and expense.  You get no points for effort or cost, only for the degree of measured improvement.

Title: Re: More panels!
Post by: ajaffa1 on June 02, 2018, 12:23:58 AM
Thanks BruceM, a little investigation shows that the entire building is wrapped in an aluminium foil type insulation/vapour barrier. The property has a tin roof which might provide some protection. The trouble is there is a large picture window facing the tower, it has a glass fibre fly mesh on the outside, wonder if someone does an aluminium fly mesh?

Doesn`t help when I`m gardening or working in my shed.

Bob
Title: Re: More panels!
Post by: BruceM on June 02, 2018, 12:36:50 AM
While the foil backed insulation will be helpful, cracks and gaps will abound (like at every outlet and light box and the base of the wall) so I would use regular aluminium screens over that big window which will provide about -22 dBm of shielding. You won't get more than that because of the gaps. etc.  Low E glass in an aluminum frame also provides about -20 dBm for cellular signals. I'm not sure 20dB will be enough in your situation, Bob.  Will know more when you can get a reading.

Another issue is that without metal siding or a foil faced sheathing board under vinyl or wood siding, all your home wiring is directly exposed.  Since you likely have corded lamps on the inside of the foil  to act as radiators, that can reduce your effective shielding by the foil to nearly nothing.  When testing ideas for low budget, lower performance shielding, I encourage testing with temporary, cheap materials such as foil faced building paper or just foil and foil tape, or a foil-plastic material such as radient guard or even space blankets. I'd put something over that window to see what you'll get with your "free" foil faced vapor barrier before blowing the dough on a screen and frame.  20dB is not a lot of shielding, but I'd take it for cheap every time.  Less than that, I wouldn't bother.



You really can't tell by looking, depends on how much power that transmitter has and whether you are centered in the beam of the antenna element covering your direction.  Readings will be highest with activity in your direction;  I don't know how rural this is and intermittent the transmissions in your direction might be.

Title: Re: More panels!
Post by: ajaffa1 on June 03, 2018, 11:56:44 PM
Hey Bruce, I tracked down the guy with the emissions testing equipment. He works as a park ranger and one of his jobs involves keeping an eye on what the Telcos are up to. I`ve invited him around and will let you know the results soon.

Back on the subject of battery storage, I have been looking into building a simple Edison battery, commercially available cells cost around $600 each . These only produce around 1.2 volts so a stack of 20 would be require to power a 24 volt inverter at a cost of $12,000. Space is not an issue where I live so I am thinking to get some 2" galvanised water pipe, cut it into 4 foot lengths and then cut a bsp thread on both ends. I will cap both ends with 2" bsp plactic pipe caps. I will then fill this with KOH which should strip the galvanising off the inside. This will become the cathode (-ve) part of my cell.

I will then drill a hole in the top plastic cap and insert a 4 foot length of 3/4 inch rebar. to increase the surface area of said rebar, I intend to place a permanent magnet on one end before rolling the rebar in iron fillings. This will then be cleaned in KOH before being nickel plated to provide the anode. Should cost less than $50 each.

If I ever get round to this particular pipe dream (bad pun  :laugh:), I`ll post some photos and data.

All advice greatly appreciated,

Bob
Title: Re: More panels!
Post by: BruceM on June 04, 2018, 12:59:40 AM
A nickel iron battery needs a nickel oxide-hydroxide cathode. Edison used an etching process to get more surface area on the nickel cathode, for modern nicad batteries a mechanical pocket forming method was used instead. 

The prices for NIFE batteries are not even close to competitive in most situations and the US manufacturer in Colorado hasn't brought prices down a bit and is now offering lithium batteries. 

Title: Re: More panels!
Post by: ajaffa1 on June 04, 2018, 08:04:29 AM
Thanks for the reply BruceM, I was aware that nickel oxide hydroxide was the preferred coating for the cathode and that it cycles between nickel 2 oxide hydroxide and nickel3 oxide hydroxide as the cell charges and discharges. I don`t suppose you know how Edison etched his nickel cathodes?

The approach I was aiming for was to produce a lot of cheap long lasting cells rather than a few expensive high tech items. I do not expect them to have the charging density of modern Nickel/Iron batteries.

Bob
Title: Re: More panels!
Post by: ajaffa1 on June 04, 2018, 09:23:20 AM
Hey Glort, I feel your pain. My solar has also dropped off a cliff. We at least have a wood burning stove to heat the place and 20 acres of woodland to provide the fuel.

I think people in Australia are afraid of insulating their properties after the pink insulation debacle. In the UK the specifications are so much higher: cavity walls with 100mm of insulation, roofs with 300mm of insulation, double or triple glazed everything. I installed a wood burning stove in my last UK home, my Wife and I would sit in our living room in shorts and tee shirts watching the snow fall outside.

I understand the idea that Australia is generally too hot, rather than too cold but insulation keeps heat out just as well as it keeps it in. If I had the time, money and strength I would be building the most heavily insulated home I could. It would have a ducted, reverse air conditioning system with heat recovery on the incoming fresh air supply.

Kingspan make a high density fibre glass reinforced insulation sheet which can easily be cut and formed into a very efficient ducting system, the addition of zoning gates (electric flap valves) ensures that you only heat/cool the areas you require.

Try to stay warm without allowing the greedy rich to get richer,

Bob.
Title: Re: More panels!
Post by: ajaffa1 on June 04, 2018, 12:16:45 PM
Hey Glort, seeing as you have almost unlimited access to waste veggie oil ( cruise liners and etc.), have you looked into the type of furnaces commonly used in the US? They are cheap, reliable and should be very easy to adapted to burn any type of hydrocarbon, simply by changing the size of burner nozzle. The only problem I can see is the spark ignition system they use to ignite the fuel. I doubt that would work with WVO but the addition of something more flammable (Kero, Diesel or RUG)should cure that. Alternatively it shouldn`t be too difficult to set up a small LPG pilot light to initiate combustion.

Bob
Title: Re: More panels!
Post by: BruceM on June 04, 2018, 05:08:18 PM
Bob, you probably know more about NIFE chemistry than I do. Edison had a patent on his etching process you should be able to find but patents typically don't give you all the needed details. It was chemically etched is all I can recall; my memory is shot.

Glort, I agree with Bob- if pouring 4KW of electric heat into the house does little, more insulation is clearly in order. I wonder what you have in your walls and attic?  Is the slab/stemwall concrete exposed outside?  7 doors and vast glass alone will certainly be a bugger for heating.

 You can imagine how in new designs, good design and insulation would save a fortune in heating/cooling system size and energy use.  For retrofit, walls can be blown, as can more insulation in the attic.  If the walls are already full then adding foam board on the inside or out is the next step. I had a 2200 SF home in Gilbert AZ (low desert- Phoenix Metro area) with 2" of foam over 6" wall with fiberglass insulation.   It cost me just under half what I'd been paying for AC for my previous 1100 SF home just a few miles away. (1/4 the energy per SF). Thermal bridging of wood framing is a lot more of an issue than people think, a couple inches of foam is worth more than just the added R value.

Super insulated home walls are typically R40 via 12" of fiberglass or the equivalent in foam and fiberglass or other.  R80 attic and at least R24 for stem wall and slab depending on soil temps. The minimum standards for new construction insulation are a farce in today's world, and should be changed to much higher levels.  Another thing that would help is to shoot the architects who design in sweeping expanses of glass for more extreme climates without some sort of insulating panels or shutters outside.  Each layer of glass is R1, roughly, so a double is R2 and triple pane is R3.  That is a thermal disaster.  Lots of doors - much the same problem, and not from leakage.  An insulated door might be R3.  I have the outside door to an airlock/coat and jacket/storage area that I only partially heat. 

One of my pet peeves is that instead of handing free money to big banks. a government low/no interest loan program to homeowners to add insulation, solar hot water, etc. should be done.  Conservation is the best payback you can ever get.  This creates jobs and would save a great deal of energy use, and could cost nothing to taxpayers. Better to spend a little more to have it well run with regionally appropriate insulation/energy upgrades with energy use data collection and publicly available so that people don't pay for white elephants. Likewise, interest free or very low interest insulation upgrades for new construction make sense.

In the winter I stuff my windows with a Reflectrix type aluminized double bubble layer material, which is worth about R8 facing the interior.  It cuts my night time loss in half.  If we have a heat wave over 100F and wildfires so I can't cool off at night passively, I stuff 1/2 of my windows during the day. I still have solar tubes for lighting and leave some of the N. windows unstuffed for light.  I also use the Reflectrix stuck to the inside of my security screen door via velcro in the winter.  It then acts as an insulated storm door and noticeably keeps the "insulated" door less frosty.  Our winter nightime temps are typically 15F but can be as low as -12F.

Pardon the rambling, please.








Title: Re: More panels!
Post by: BruceM on June 04, 2018, 11:16:52 PM
Thanks for being generous about my rambling, Glort. I'd look into the wall and ceiling insulation situation, as well as duct insulation. 12" fiberglass is the standard ceiling insulation here, but if walls can be raised to R19 then I'd want more than that in the ceiling.  Your wall that gets sun and warms up in winter; yes, but loss all night as well...the same problem as glass.  The only wall heating you really want is a Trombe wall with some sort of insulation outside at night.  Perhaps that sunny wall could be used for a hot air panel- which could be covered in summer?

I'm really spoiled in my new house-  with double framed R40 walls,  the west wall doesn't heat up inside at all in the summer.  For my new neighbor's upgraded and enlarged version of my house, I convinced him to have no windows at all on the west wall. I foolishly put a small one in, thinking better night time air cooling in summer, but have found it best to keep it covered with an outside insulating panel all year round.

If only foil in walls-  egads.

Another thought-  how about adding a large radiator in the central air handling system...with a hot water circ pump  loop from your own DIY veggie oil boiler.  The boiler would be quite a project... but with your oil experience...
Title: Re: More panels!
Post by: ajaffa1 on June 04, 2018, 11:42:16 PM
Hey Glort I vaguely remember a very cheap type of double glazing being available in the UK. It was a self adhesive clear film which you stuck to the window frame. A quick once over with a hair dryer and it would shrink tight and become invisible, trapping an insulating layer of air between the glass and the film.

Wish I could remember what it was called.

Bob
Title: Re: More panels!
Post by: ajaffa1 on June 05, 2018, 12:09:16 AM
Thanks BruceM, Interesting video here showing how to make Nickel oxide hydroxide using readily available, cheap chemicals.
https://www.youtube.com/watch?v=qB6B6u0qe_I

Bob
Title: Re: More panels!
Post by: BruceM on June 05, 2018, 01:11:38 AM
Interesting video, Bob, thanks.  How will you apply the paste to your plates?

I've used the 3M storm window film kit- it works fine.  The exterior version holds up OK, there is also an interior version.

Title: Re: More panels!
Post by: mike90045 on June 05, 2018, 01:28:53 AM
NiFe batteries, I have them.   Chicom versions.

The edison ones were pocket plates, packed full of nickel shavings to get as much surface area as possible.  They weren't slabs of metal
Title: Re: More panels!
Post by: ajaffa1 on June 05, 2018, 05:17:31 AM
Hi BruceM, how to apply the paste is the question. Finding some sort of conductive adhesive which isn`t going to dissolve in KOH or upset the electrolytic reaction is tricky. That`s why I originally planned to make something conductive with a large surface area and then electroplate it with Nickel.

Mike90045 believes that the original Edison batteries contained flakes of Nickel rather than nickel oxide hydroxide.

More research required I think.

Bob
Title: Re: More panels!
Post by: BruceM on June 08, 2018, 03:27:55 PM
Sydney is only 33.8 degrees south; so just imagine trying to collect winter solar energy at higher lattitudes N or S. Vertical panel orientation is often used, and only 4 hrs of useful production in southern Canada.

I'm at 34.8 degrees north, so I have similar to Syndey winter decline in PV production.  It's all about panel orientation for winter. Summer is a time of grand excess because of all those hours of production.

My daily electrical power use is about 2.7 KW in winter including 12V for circ pump (heating and solar collection) and sunny day electric cooking.  My refrigerator is propane which saves 1 KW/day. It's worth the $15/mo propane bill for the blissful silence.  Of course this is a 1100 SF house and just one person, solar heating and super insulated.  But looking like 1/15th the electrical energy use, despite being much colder at 5600 feet elevation. My solar hot water panel is collecting 26KWH worth of heat on a winter day at roughly 800W per 16SF flat plate collector x 8 (128 SF total) for 4 hours.  That 83% efficiency for direct solar hot water heating compared to 15% for PV pays off big time in winter. 

In looking at Sydney climate data, your winter temps are so mild that your problem is clearly one of throwing energy outdoors.  Improving insulation should dramatically improve the situation and make the house more comfortable all year round.  Solar hot water heating would work there, too, but I'd always start by seeing what could be done to improve insulation.  Insulation pays back for the life of the house. A good legacy.















Title: Re: More panels!
Post by: BruceM on June 09, 2018, 12:45:43 AM
Lots of single pane glass will certainly be problematic.  It's approximately R1.  It's area relative to ceiling and walls and their average R values for a room will determine your average R value and thus loss.  Insulating curtains or shutters for night time could greatly improve night time losses, when they are highest due to larger delta temperature.




Title: Re: More panels!
Post by: BruceM on June 09, 2018, 03:50:15 PM
Some of the window films as Bob suggested are very good optically and will perform similarly to double pane glass- doubling your window R value to about 2. 

There are plenty of sun angle calculators online for shading.  Deciduous trees can be quite marvelous for seasonal shading.  My Siberian Elms now shade my summer patio from the eastern sun so that it does not heat up.  West walls can benefit greatly from deciduous tree shade or vines on trellis when insulating them adequately isn't possible.
Title: Re: More panels!
Post by: Hugh Conway on June 09, 2018, 03:52:29 PM
Up here on the coast at 50* N it's quite  cloudy in winter. Around the winter solstice, even if the sky is clear, the sun does not rise above the trees, so we get no solar input. Same for the solar collector for water heating, though the woodstove takes over that chore from October to April. The Listeroid comes in handy for topping up batteries then, and logs about 300 hours annually. We are using about 2 to 2.5 kwh per day.
Re: heat loss through the windows.......even curtains drawn at night help a lot.........and wife likes them! Double layers help even more. Our biggest heat loss is from opening/closing/opening the doors for our old dog to go in and out. Sometimes he can't make up his mind.
Cheers,
Hugh
Title: Re: More panels!
Post by: mike90045 on June 13, 2018, 04:26:52 AM
> Our biggest heat loss is from opening/closing/opening the doors for our old dog to go in and out. Sometimes he can't make up his mind

That sounds like feline behavior   :D
Title: Re: More panels!
Post by: BruceM on June 13, 2018, 03:36:54 PM
Film has the same effect of double pane; adds R1 to your R1 single pane. That cuts your loss in half.  An insulated shutter for night is much more effective but is a building project.

I only use film on one window (already is double pane) for the winter; the frame sweats too much otherwise.
Title: Re: More panels!
Post by: BruceM on June 25, 2018, 04:34:49 AM
Cold tile on slab floor usually means exposed slab or stem wall outside with no insulation. (Foamboard and metal or foamboard and cement board.) Consider adding some- even a little will help greatly.  If there's a concrete walk outside against it, you're screwed.

Our night time temps are creeping up, I could only get the house down to 74F by this morning. 78F now, too damned hot for me.  I need to work on the inverter and then water chiller for in-slab cooling.



Title: Re: More panels!
Post by: LowGear on June 25, 2018, 07:38:52 PM
R values are not linear.  R2 is not twice as good as R1.  R1 is the butt kicker.  I seem to remember R10 being rated at something like 90% efficient what ever that means.  And R20 being  something like 93%.  Okay, time has taken it's toll but the relationship is close to those numbers.

In fact, back in Washington state those liberals passed a law making window sales people stop saying that R2 windows were cost effective because of energy transfer.  Quality of life - Yes!  Heating - cooling bills; No.
Title: Re: More panels!
Post by: BruceM on June 25, 2018, 08:15:09 PM
Alas, Casey,  the loss through the window glass alone, R2 really does have half the heat transfer as R1. The R scale really is linear.  Marketing types will make up all kinds of nonsense, but there is no such thing as "efficiency" in R values. It only relates to the rate of heat transfer.  Physics, not BS.  R1 is the heat transfer rate of 1 inch of soft pine.  Most blond foam boards (isocyanurate) have an R value of 6-7 per inch.  Straw bales are about R 2.5 per inch.  The insulation and building industries have done a great job at marketing BS, and I know one former building inspector who actually believed that 1/8 inch of fiberglass with a foil facing on the outside of a block wall was going to insulate his home to some fantastic effective R-value as claimed by the seller.  He had to throw 8KW in space heaters to supplement his in floor heat- even combined they could not keep up on windy cold nights. 

https://en.wikipedia.org/wiki/R-value_(insulation)

The R value of the insulation is often defeated by thermal bridging by wood (R1 per inch) from siding to wallboard, and also for fiber insulation, by air infiltration...thus the (typically shoddy) use of wind wraps.

Window loss is only a modest percentage of the total of outside surfaces and losses so halving your window glass loss may mean diddly squat in your power bill.   In a well done, super insulated home, window losses dominate; by the thermal model I used for my home design, my modest sized double pane window losses are now 50% of my total loss. It also is confirmed when I cut my 15F overnight house temperature drop by almost half when I cover them with Astrofoil (similar to Reflectrix- foiled double bubble).





 



Title: Re: More panels!
Post by: LowGear on June 25, 2018, 09:50:49 PM
Damn Readers Digest and all of the dead legs I've suffered because some pervert left them next to the toilet.

But on a slightly different note.

I had a revelation while pulling weeds this morning and it was inspired by one ajaffa1's recent posts.

I have become somewhat of a bore on anti petroleum and coal energy production.  I apologize.  This is my favorite forum and I will be getting back to basics from now on no matter how much I'm baited (see, I'm the victim).  Thanks for your time and energy.

Aloha
Title: Re: More panels!
Post by: BruceM on June 26, 2018, 03:29:55 AM
Windows can be big loss in an otherwise well insulated house, but how it affects the total heat or cooling bill depends on what percentage of loss is windows.  People get suckered into spending a fortune on double pane windows as a retrofit when their money might have been better spent elsewhere, like insulating shutters or curtains, and increasing other insulation. 

For winter heat loss, look at the total outside surface areas- walls and ceiling and exposed masonry/concrete slab edge. if you calculate the area of each type surface and it's temperature in degrees below room temperature, you will will have a good measure of the relative contribution of window vs wall vs door vs ceiling vs outer floor area vs inner floor area.  Then you can estimate how your proposed insulation will affect the total BTUs needed in that room.

For windows with solar gain in the winter, insulating shutters are the hands down winner unless you have too much gain.   On my previous home I made the mistake of way too much passive solar gain- all double pane glass on the south (northern hemisphere). The view was awesome and the daytime gain was so sauna-like that windows had to be open to keep it below 85F in the dead of the winter.  But the night time loss was so great that the rooms would be 58-60F in the morning.  That was very educational.  I had to add thermal shutters to all the windows and patio doors.  I later added reflective mirror film on the outside of all the south glass to cut down the gain, which was a huge help in the summer as well.

 For the thermal models, you have crank in all that data plus outside temperature, wind and soil temps and then you can play what-if's to see how it affects your BTU.  That's how I was able to figure out how to optimize my home insulation for my climate while on a low budget (plus 6 years of sweat equity). The biggest bang for my buck was the perimeter insulation; I had no idea that so much heat was lost through the outer floor in a slab home.  That's the reason so many in floor heat (slab) homes are so expensive to heat- heating mother earth is a loosing game.  The earth is NOT a good insulator at all, and even in our arid climate the one place that stays damp even in summer is under the slab and next to the footings.


You will certainly notice the cold convection draft from windows and solving that will help with comfort as well as some heating cost.  Just remember it's the total surface area x temperature drop below room temperature that makes your heating bill. 

For your situation only the parabolic trough solar hot water collectors would work as you must have high temperatures to use a radiator in your forced air system.  Which reminds me-  take a good look at your duct insulation; half your electric heat watts may be wafting out your gable vents and draping additional fiberglass bats over the duct work might be well worthwhile. 

Title: Re: More panels!
Post by: BruceM on June 26, 2018, 06:40:41 AM
Where exposed, slab edges are a big thermal problem both winter and summer unless you have a thick carpet pad and carpet as insulation.  (I think carpets are toxic indoor air polluters myself.)  Check the floor temps from the wall inward to see for yourself and use the temperature change below room temperature time area to figure the contribution to room losses.

A strip of 1.5" (EPS-R9) beveled edge foam board with some metal trim made to cover it and tuck under the siding, in a suitable color works well. Ideally it should go down to the frost level. (Not far for you.)  Most siding companies that do metal work can bend prefinished steel trim pieces to your dimensions. They usually have a wide selection in colors. There are some composite and cement board products used to cover foam perimeter insulation but that's less likely to be useful as a retrofit.

If you look at some plans online for foundations for the latest low energy designs in Germany you will see massive use (10s of thousands of dollars worth) of high density EPS foam around the foundation.  My climate is milder and frost line is only 16 inches so I was able to avoid the special molded foam products and roll my own simpler design.  For my new neighbor's home I had him increase the sub-slab 25 psi  EPS (blue board) to 3 inches for the outer 4 feet, plus the same 4 inches between slab edge and stem wall, and 1" outside the stem wall down to the footing.  The edge insulation is very cheap for it's performance.  The sub slab insulation adds up fast because of the area but the savings in being able to greatly downsize the heating system pays for the foam even before the first fuel bill.  We can hide the 4" of foam between slab and stem wall by having the 12" wall- the inside framing (non load bearing steel studs) sits on the heated/cooled slab.  The top block of the stem wall is only 6 inch to allow for an extra strip of 2" foam only 1 block high.  The second 2" foam goes all the way down to the footing. 

You may be able to find a good free thermal model to play with...it's tedious and time consuming but very educational.


Title: Re: More panels!
Post by: ajaffa1 on June 26, 2018, 01:09:25 PM
Hi Guys, I spent a lot of time in the French/Swiss Alps building in summer, skiing in winter. The issue of cold bridging is horrendous when you have temperatures as low as minus forty centigrade at night. Any property without sufficient insulation will be almost uninhabitable and have every water pipe burst. Cold bridges will very quickly identify themselves due to the condensation/ice that forms and destroys the interior finishes.

Remarkably they build primarily in concrete which has next to no insulating properties. The trick is to build the shell in concrete and then completely clad it in 150 mm of urethane foam with special attention to window and door reveals. Add triple glazing and you are in with a chance of staying warm. I wonder what they are going to do after the Grenfell tower disaster in London, can`t imagine they will strip all this flammable insulation and replace it. Skiers beware!

I did see the aftermath of a fire in one block of apartments in Val D`isere, wasn`t much left. Thankfully it happened in summer when the building was pretty much vacant.

Bob

Title: Re: More panels!
Post by: BruceM on June 26, 2018, 03:05:09 PM
There is much to be learned from designs for extreme climates; I borrowed from Canadian double framed wall designs.

An issue that I don't think is being considered enough is indoor air quality.  Air to Air heat exhangers will help dilute indoor pollution but reducing the pollution in the first place seems wise.  I used aluminum foil laminated to the mudded drywall and sealed at electrical boxes and base of wall to block wall and insulation materials from outgassing to the home interior.  The foil is finished with tile (we now use magnesium oxide cement as adhesive) and clay putty/paint - no exposed foil. The foil doubles as part of radio/microwave shielding and my house was measured at -110dB (voltage) or -55dBm (decibles of milliwatts of power) worth of shielding at 2.4 GHz.  I didn't need that much shielding for my rural location (until a cell tower goes up nearby) but wanted so see what was practical to achieve for whole house shielding without having the house look too odd and on a pretty tight budget.  I used heavy duty screen frames with 50 tpi stainless steel mesh as over-screens to shield the window openings. It was quite a design and construction effort. 
Title: Re: More panels!
Post by: ajaffa1 on June 26, 2018, 11:16:56 PM
Hi Bruce, double walling is a very good way to reduce cold bridging all modern UK homes us it. Interestingly they used to sell drywall backed with aluminium foil as a vapor barrier, don`t know if it`s still available.

Bob
Title: Re: More panels!
Post by: BruceM on June 26, 2018, 11:49:17 PM
The foil backed drywall is still sold in the US, but at a very high price. It is of no value as a vapor barrier unless you gasket all the seams, and still it will leak since it's penetrated by so many screws and is so thin it's full of micro-perforations.  We changed to laminating 1 mil (0.001 inch thick) foil on the mudded drywall and it's a vast improvement- thick enough to stop nasty insulation odors, no perforations, way cheaper than the foil backed drywall and a much better result.
 






Title: Re: More panels!
Post by: LowGear on June 29, 2018, 01:52:11 AM
Quote
Alas, Casey,  the loss through the window glass alone, R2 really does have half the heat transfer as R1. The R scale really is linear.

Hmmmmm.  So I'm standing on a barren mountain and it's cold.  I have a glass greenhouse put around me and it's warmer.  I have a second glass greenhouse put around the first greenhouse and it's not as cold.  A third and .......  That first greenhouse just has to have the greatest impact.  Of course I'm mixing R values with infiltration however the difference between greenhouse 1 and greenhouse 2 are not as great as that first greenhouse.  The marginal equivalence between greenhouse 1 to 2 and 19 to 20 just can't get past the little gray cells in my head.

I'm thinking that the 1 inch pine greenhouse might be a bit different than the single pane glass one?

Thinking is bothersome.  Give me a Readers Digest article in the throne position and you have me by the little gray cells for life.

My other educations have led me to believe that infiltration is the bad boy of heat loss especially in older houses.  I'm surprised that humidity hasn't come into the conversation yet.
Title: Re: More panels!
Post by: ajaffa1 on July 17, 2018, 12:38:43 AM
So much for global warming. Frosty here too, below zero in Grafton is unheard of, hope it isn`t going to kill my mango tree.

Have you thought about fitting wooden shutters to the windows? Painted up they can add a lot of character to a home and deter burglars.
Title: Re: More panels!
Post by: BruceM on July 17, 2018, 02:40:41 AM
Inspired by Glort's home power work, I've been working on my ultra low EMI inverter again in the last 10 days, both hardware and software mods. I did my first load of laundry with it about 5 days ago. By a minor miracle my MS related brain fog has lifted a bit lately.  I'm fine tuning at this point, set up with modified toroidal transformers for 230VAC (true RMS via shifting the width of the 5 step waveform), and am adding circuitry for remote control. The two H-bridges that do all the heavy lifting, power wise, only draw 5ma of 12VDC when "off" (open circuit outputs) so I am NOT adding an additional solid state relay for remote inverter control. Instead I'm just having the processor shut down the H-bridges and turn it's own power off. Running it and the H-bridges total 55ma of 12V. 

I just did an efficiency test with my two Antek transformers late this afternoon and am pretty pleased-  94% at 1000 watts of load.   Idle (no) load is only 14.1 watts (0.10 amps at 141V).  Efficiency could be improved by going with custom transformers but only a few percent.  I modified them with 64 added turns to the secondary windings.  There's presently a 1.6% loss in DC filtering to keep my 120VDC clean.  I have only 1 mv of 240 Hz ripple on the 120VDC supply at 1000 watts of load. I made a 14 MH choke/reactor for the first stage of the filter, using a 400W toroidal transformer core I gapped and wound with 118 turns of 12 awg. It works well but I lose 1.5V right there at 1000 watts of load, should have used 3 strands of 14 awg.

It's been a very educational project, and I'm looking forward to calling it quits on improvements and just putting it into service up in my battery bank shed.  But while I have it still on the bench it's hard to resist fiddling with it.

Title: Re: More panels!
Post by: BruceM on July 18, 2018, 04:39:48 PM
My clever design to remotely control the inverter without adding a solid state hv relay resulted in some failed power mosfets and ics.  My memory is so poor I forgot the high side of the h-bridges is powered by swinging capacitor which is only charged when it's mating low side mosfet is on, so the h-bridges can't be used as solid state switches.  i now remember figuring that out later last year, but it slipped. 

Back to the drawing board. 

 
Title: Re: More panels!
Post by: BruceM on July 19, 2018, 04:04:16 AM
Nothing like the school of the real world, that's for sure.  Studied the problem and have come up with a few solutions but will mull it over a bit more.  If I change the H-bridge circuitry polarity so that with the inputs off, the low side transistors are on (shorting the transformer primary), with a corresponding inverse change in in the data table that defines the sequence of events in shaping the 5 step sine, then I COULD use the H-bridges as solid state switches.  When the processor is "off", the low side transistors being ON will keep the high side power topped up, and the high side transistors will stay safely off.

I just hate to make a mess of my custom H-bridge PCBs-  they are clean- no cuts and jumps, and very dense since I had to squeeze it all onto the small "experimenters board" size.  I also like that it is presently all "positive logic" in software and hardware (1 is on or higher voltage) and the high side or low side circuitry is identical. It helps me keep things straight in my addled brain.

It's been fun luxuriating in my huge to me increase in PV power.  I've been using my shop heat lamps for load testing - while the sun shines I can turn on 1500 watts and still (just) keep the batteries in float charge.  Someday I'll turn that into water chilling for house cooling...




 

Title: Re: More panels!
Post by: BruceM on July 19, 2018, 04:05:55 PM
"Modern Architecture" has been largely about sweeping expanses of glass...which is a killer for thermal performance.
There is an architect in New Mexico who preaches and writes about "eco" housing, now using straw bales but previously cast pumice-crete.  Some wealthy friends (wife with severe MCS) paid her over $40K for house plans I reviewed.  I was flabbergasted. Her plans had pumice-crete poured right down to the footings with no barrier to stop damp earth moisture and bacteria wicking up into the house wall, and no vapor barrier on the inside to stop moisture migration into the pourous cement wall in winter (it was to be raw plaster finish).  Damp portland cement walls are notorious for causing health problems and became infamous for that in Germany when so much low income housing was built after WWII with cast concrete walls. It was known as "the concrete sickness". The interior walls were all pumice crete cast over thickened slab...so good luck ever making any changes for wiring or plumbing.  The slab details showed it was NOT insulated- yet the home was in floor heat(!).  Oh, and as drawn, for a small home of about 1400 SF, she had 4 levels of roof, and no means of support for the roof over the center of the L shaped home.  The open L courtyard faced the prevailing SW wind in an area notorious for high winds.

I don't think most people realize that architecture is ART SCHOOL.  Very few rise above that and actually try to learn something.

My plan for the house cooling is to run a 1.5 hp water chiller in the in floor heat system water.  Once I finish the inverter project I'll have to research details of propane and mineral oil for refrigerant.  It's the devil in the details bit that is a concern, I'm on a low budget.  It's got to be cheap since I will rarely use it; it's only during wildfires and/or controlled burns that I can't cool the house adequately by just opening the windows at night. 














Title: Re: More panels!
Post by: broncodriver99 on July 19, 2018, 07:52:33 PM
My plan for the house cooling is to run a 1.5 hp water chiller in the in floor heat system water.  Once I finish the inverter project I'll have to research details of propane and mineral oil for refrigerant.  It's the devil in the details bit that is a concern, I'm on a low budget.  It's got to be cheap since I will rarely use it; it's only during wildfires and/or controlled burns that I can't cool the house adequately by just opening the windows at night.

I can see 2 possible issues with that that you may want to do a little research on before committing.

First is the latency you will have with all of the thermal mass of the concrete. It would likely take a day or two or maybe more depending on your refrigerating capacity to cool the slab enough that you would realize any cooling benefit to the room and then it would be marginal. Remember, heat rises so any cooling benefit would likely be to the soil unless the slab is extremely well insulated. I can offer some real world info as far as the amount of horsepower it takes from my day job if you are interested.

Second, would be the temperature necessary to have any benefit and you would likely need airflow across the slab in order for it to absorb the heat. IIRC you are in an arid environment so humidity may not be an issue but if at any time your slab drops below dew point you are going to be making condensate all over your floor. It happens here on the East Coast all of the time.

If you are trying to minimize electrical usage(ie no fans/blowers) you could also look into a gravity refrigeration system. They require a lot of suspended piping and don't have a lot of thermal storage capacity unless you bank ice or have a large reserve of chilled water. The best time to bank ice is at night though when there is no solar available.
Title: Re: More panels!
Post by: BruceM on July 19, 2018, 09:09:07 PM
Glort,
Using the Lister to run an auto compressor is out-  it's 400 far away, over a hill.  Running the Lister as generator for a compressor is fine, since this is so rarely used.  But it would be neat if I could use my inverter to handle it during the day...I could use it more often which seems to be the trend for the SW US.

Window AC units direct would be the obvious solution but I can't use them, for ELF magnetic fields, sound, air quality and wrecking the shielding that my home provides with it's fine stainless mesh screens over all the windows.


Bronco,

Your comments were thoughtful and right on the mark for a typical home in a typical setting. 

Most conventional in floor heat systems in a concrete slab home are so badly designed that yes, for heating or cooling mostly you are trying to change the temperature of the earth and outdoors.  My home is only 1100SF and is superinsulated, including the 5.5" thick slab.  On a 100F day it gains 3-4 degrees.  The house air temperature is 2-3 degrees above the slab temperature.

In floor cooling has been well tested in concrete in floor heat systems in a study paid for by New Mexico state.  They were using night sky radiation via unglazed solar water panels on flat roofs to chill the water.  Their goal was to just remove heat load from the building overnight...and this it did quite well and for very low cost.

After reading the reports from NM, at elevations similar to my own, I did some testing on night sky radiation/evaporation cooling via water trickled down steel roofing measuring delta temperature, temperature, humidity, wind and flow rate.  It is viable but if there is no wind, and no clouds it requires a minimum collector area of 1000 SF for my 1100 SF home.  That's a lot of corrogated steel roofing.  If there are clouds, there is no night sky cooling so it is not a certain thing.   Using the shop roof for night sky cooling would be possible but is hell on the roof since the well water is pretty high mineral content. I'd rather put the steel on racks just above the ground, which also removes head so a 20 watt DC pump would easily manage the water flow at the minimal lift needed.   

My neighbor and I did some experimenting with running his 65F well water through his 900SF shop floor a few years ago.  It worked so well when the slab temperature was 10 degrees and more above water temperature that when he was living in the shop during home construction he ran it every afternoon to cool off the shop. His shop and slab is also insulated but not nearly as good as his and my homes.  Based on the flow rate and temperature rise, I did calculate that the typical BTU capacity of a 1.5 HP compressor was just adequate for my house.  65F water isn't really cold enough for a desired 72F...not enough delta T; you really want 55F water.  Running it for 4 hrs during the middle of the (summer) day when I have excess PV capacity should suffice to lower my house temperature the necessary 3-4 degrees.  My need would mostly be for June wildfires, where there is no shortage of PV power in the day.  My battery system isn't designed for carrying 1200 watt loads at night.

I did monitor indoor temperature and humidity here during the intended cooling period of June through July and there is plenty of margin so no chance of sweating floors in my climate here.  The floor mass is being cooled only a few degrees in a day... it will well above the dew point.  As you noted, it is not possible to use in floor cooling in a more humid climate because of the floor condensation, and besides, dehumidification is much desired.

My concerns about window AC units converted to propane are- can they be used on fuel grade propane, and how do I insure the right type and amount of oil...and concerns about purging the original oil. I have 10 gallons of white mineral oil so of course that is an appealing lubricant. 














Title: Re: More panels!
Post by: broncodriver99 on July 19, 2018, 09:38:21 PM
My concerns about window AC units converted to propane are- can they be used on fuel grade propane, and how do I insure the right type and amount of oil...and concerns about purging the original oil. I have 10 gallons of white mineral oil so of course that is an appealing lubricant.

I don't know that there is anything to be gained from converting window AC's to propane. They have to meet pretty strict energy requirements now so any modifications made would likely be detrimental to their efficiency and performance. I would run them as is and if one fails and you are inclined to experiment with it then so be it but you will likely never get it to produce the same cooling for the same amount of energy by changing the refrigerant and taking it out of design. Not to mention longevity.

About the best thing going these days is inverter driven mini-split systems. The efficiency they are getting out of them has gone through the roof in the last few years. Typical now is ~30 SEER which use ~40% less energy than a higher end EnergyStar window banger. They also perform very well in hot arid environments. Mitsubishi just came out with the smallest one on the market @6000 BTU which sounds about right up your alley, it has the ability to modulate down to about 1700 BTU/hr or overdrive up to about 9000 btu/hr when needed. There is also a company that makes one that can use solar PV directly into the units inverter to offset some of the load required on the AC(power) side of things. I will see if I can find their info for you.

The big question is how well they will run on an inverter and whether they will introduce any unwanted EMI to your situation. They do make some that can be ducted and you could likely then counteract any EMI if it is an issue.
Title: Re: More panels!
Post by: BruceM on July 20, 2018, 12:34:05 AM
The only point of changing refrigerant is that I have to modify the plumbing to add a stainless flat plate exchanger to cool the water so would have to evacuate and recharge. Propane is essentially free.  But I can keep it the same. Do you see a problem with using a stainless flat plate collector as the water cooler/evaporator?  I was thinking of some 1/4 tubing inside my gas hot water heater (used as a low BTU boiler) as an alternative. 

I agree split systems are a good choice, but fan motors in the house are a bust for me.  I can look into split system compressors, and see if there are any small enough.  The existing in floor system provides a way to extract the heat from the slab without and noise or motor EMFs and winding/bearing odors.  I'm not well at all, I didn't do a 120VDC powered, paintless and fanless interior home for sport, it's so I can function well enough to live independently.  I don't last long in normal homes.

I just finished fixing my inverter h-bridge with the 2 popped mosfets and one fried IC. Back in working order and tested out fine.

I decided to go for the PCB modification to solve my remote inverter on/off design goof.  I modified them both with 8 cuts and jumps each to reverse the polarity of the low side switches. Now with the microcontroller off, the H-bridge can be left powered, still drawing only 5ma of 12v and no extra solid state HV DC switching is required for my remote on/off control. The low side switches are both on, so the "resting state" is now with transformers shorted, and this keeps the floating high side powered (and off). (The design of powering the high side via capacitor, charged only when the output is being pulled low by the low side is commonly known as the bootstrap capacitor method.) When operating the inverter draws about 50 ma total of 12V, but when operating it is powered by a low voltage winding off one of the transformers.

Next up I have carefully modify the 19 step data table for the inverter gate control bits. I've got to invert just the low side bits.  It won't be pretty if I screw up, there is no built in hardware protection to prevent high/low dead shorts.  I didn't want to add the additional logic ICs and instead check the outputs via logic analyzer after every software change, no matter how trivial.





Title: Re: More panels!
Post by: BruceM on July 20, 2018, 12:56:32 AM
I just looked at some split system condenser units-  there are some small ones that fit my power budget, and would be perfect for my water chilling approach if only I can sort out the water chiller part.  Thanks BroncoDriver!

Looked again.  Alas, they are using "inverter" drives for variable speed operation, so I won't be using these. They are an EMI bomb.  I need something with a regular single phase motor, no frills.

Title: Re: More panels!
Post by: broncodriver99 on July 20, 2018, 02:48:43 AM
Bruce I didn't put two and two together that you were modifying the window units to be the water chiller you mentioned. I must have missed it somewhere, it makes more sense now. I see no reason a stainless brazed plate HX wouldn't work just fine. They make plenty that are refrigerant rated. I will look through some of my tech books and see if there is a compatibility issue with POE oil, the oil likely in a window unit compressor, and propane. I have never seen them recommended for use together but it doesn't mean they aren't miscible.

As far as the mini-splits I thought the inverters may be a problem. There are a couple of companies starting to make small chillers with them but I think 18,000 Btu is as small as they go.

As an aside, just to give you more to think about, 24VDC variable speed compressors are available pretty cheaply these days. Being an electronics guy you could likely come up with a control system for one, the simplest ones just vary the voltage. Being as your load will be pretty constant and intermittent use I think you are on the right track with a modified window banger chiller though. Cheap and simple. Any idea what kind of capacity you are looking for?
Title: Re: More panels!
Post by: broncodriver99 on July 20, 2018, 03:04:20 AM
I just looked at compatibility sheets on R-290(propane) and R-600(isobutane) and both can be used with POE oil. The only note is that it may cause increased viscosity in the oil. So, you don't have to do an oil change unless you just want to. Just make sure you don't leave the system open as moisture contaminates POE very quickly.
Title: Re: More panels!
Post by: BruceM on July 20, 2018, 03:32:49 AM
I need 10-12K BTU's cooling capacity, power budget is about 1200 watts running including the condenser fan. 
I'd love to do ground source but can't justify it for such intermittent use. 

It does begin to look like hacking a window unit is my best bet.  I liked the split system condenser approach because of the nice already built outside enclosure.  Pity they've all gone to variable speed inverter drives.  Grrr. 

The Danfoss 24V compressors are not something I'd want to use.  Again, because they are doing hard and fast switching for brushless DC motor control with no concern for conducted EMI.  Plus I don't have 24V anyway.  The beauty of induction motors is no conducted EMI.  You still have low frequency ELF magnetic fields, but distance solves that. 

I seem to be dropping words in my sentences today. Too much soldering and live circuit checkout on the inverter.  I'm tired and scatter brained.



Title: Re: More panels!
Post by: BruceM on July 22, 2018, 02:14:53 AM
After another 3 blown mosfets, and a lot of bench work over the last 2 days, I THINK I finally have my inverter remote on/off issue figured out.  Previously, I manually switch on the 120VDC supply in front of a two stage, massive LC filter.  The result is the h-bridges see a slowly rising input voltage.  Ditto on shut down.  It worked well and could even startup with load connected without a problem.

Then I tried to add a feature for remote on/off, using the existing H-bridges as the solid state switch, since they only take 5ma of 12V when idle. The processor gets powered off to save power.  When I start the inverter  via powering up the processor, it is starting with full voltage, and always on the positive going half wave.  On shut down, it detects the shut down request after the positive going half wave and stops.  This leaves residual magnetism in the 1000 watt toroidal transformer core, so that on the next start, the current surge is great enough to trip the 15 amp breaker per H-bridge ...which causes an input spike (my very slow switched design is sensitive to that) which pops those mosfets.

Two days of work to figure that one out, and a whole lot of test setups.  I was just SURE the software guy screwed up...but exhaustive testing via single shot logic analyzer captures vindicated software.  Removing the transformers and driving light bulbs, the processor turn on/off works flawlessly.

Now I have to think about just sticking with the slowly ramping up/down of the voltage via a solid state relay before the big dual L-C power filter, changing my on/off remote control board significantly. Plan B:  add no new hardware by adding a bunch of tricky software to do soft "starting" of the transformer by a special ramp up of alternating polarity pulse widths.  Damn hardware guys always expect software to solve everything.  ;)

I'll have to sleep on it to decide which way to go. 

Title: Re: More panels!
Post by: mikenash on July 22, 2018, 04:45:17 AM
Good on you Bruce

When I read this, I feel like our ex-Jaffa friend who would rather discuss erectile disfunction while standing naked infront of an audience of nuns than attempt electronic work . . .

I'm glad somebody knows how to do that stuff . . .
Title: Re: More panels!
Post by: BruceM on July 22, 2018, 06:12:52 AM
The nuns and erectile dysfunction line was hilarious.  Cracked me up.

I've been forced to learn power electronics since moving off grid but it was never my field or in my experience.  Necessity being the mother of invention I have proceeded to lurch my way through with many missteps.  Highly educational though frustrating at times.  Rough spots or outright disasters are perhaps the biggest opportunities to dig deep and learn. I really enjoy learning new things, even though now the "evaporation" rate is alarming.




Title: Re: More panels!
Post by: BruceM on July 24, 2018, 12:46:07 AM
More fiddling about and some research and I solved my problem with some new "soft start always positive" and "always negative" shut down software.

It seems large toroidal transformers with high efficiency grain oriented steel laminate cores are notorious for whopping big start surge currents; so bad they typically resort to things like a current limiting power resistor with a time delayed relay to bypass it after startup. One company even sells an electronic soft starter.  For my testing I stripped down to driving a single transformer/h-bridge with a small fast blow inline fuse to protect my H-bridge circuitry.  The Antec 1000W tranformers I switched to when changing up to 230VAC would pop my 15A per H-Bridge breaker.   The surplus Toroids International 1100 watt transformers I used during all my early testing at 120VAC output (with both secondaries configured at 90V, so 180V peak) did NOT blow even a 1 amp fuse even without any soft start pulses. So the problem was clearly the start surge current of the Antec transformers.

That encouraged me to try fiddling with my own soft start routine.  After a pile of fried fuses,  I found that starting at 50usec wide 140V pulses, positive then negative, and incrementing by 50 usecs each cycle until pulse width of 3000 usecs (3 milliseconds) with a fixed 4 msecs between did the trick.  After that it starts the normal sine generation.  Now I can start the Antec transformers with the full 140VDC, even on 1 amp fuses, though they do blow after 4 starts in rapid succession. The soft start is about 1.5 seconds and makes funny winding up sound. The soft start pulsing is done so that the transformers don't add, it's only one or the other.  The inverter AC output is switched into my 230 VAC line from the generator with a 230V coil relay so it's won't attach itself to the load (and disconnect the generator) until after the soft start is complete and full voltage is available. If a motor load is left turned on, it won't see the oddball, low voltage soft start.

My next step is to modify the secondary transformer windings, again, to get my peak voltages with 140VDC input down a bit.  I overshot the last time exactly by factor of two... I goofed on the math.

I'm very pleased I was able to solve my remote start problem without adding a bunch of hardware, and I'm glad that what I've learned about large toroidal transformers answered a lot of mysterious problems I had during the switch over to 230VAC.  When it's all my own software and hardware, I tend to suspect that first...


Title: Re: More panels!
Post by: BruceM on July 24, 2018, 04:03:38 PM
Glort, please remind me, is your cloud effect overvoltage on the DC (panel) side of the inverter, and exceeding the max allowable input voltage, thus causing an inverter shut down?  If so, what's the max allowed voltage and what's your panel series configuration? 

If it's on the DC side, one (or more) panel in each series string could simply be shorted via DC SSR, dropping voltage by about 24-30 volts.  Mager brand DC SSRs from China are pretty cheap and I have a couple of their 40 amp - 230V ones I could test for you.  A simple peak voltage limiting circuit could do it automatically.

Title: Re: More panels!
Post by: EdDee on July 25, 2018, 09:03:59 AM
Hey Glort,

An insult and a compliment all in one.....

You have great taste and judgment in your current missus..... Pity she has the opposite in men!!

But seriously though... Wish her well and a speedy return to home ground...

The washing pile must be over 6ft by now!

Cheers
Ed
Title: Re: More panels!
Post by: ajaffa1 on July 25, 2018, 09:27:38 AM
Hey guys, before I had my accident and subsequent heart attack, my missus went to Sydney to care for her ailing parents. She was away almost six months and my electric bill dropped to almost nothing. That said I spent a small fortune on take away meals.

I finally got to the root of the problem when she returned and fired up the tumble dryer. Why anyone would use a tumble dryer on a forty degree centigrade day was a total mystery to me, she tells me it activates the fabric conditioner and removes the fluff, dog hair and etc. Sounds like a crock of sh1t to me.

Glort, hope your wife is continuing to make a good recovery.

Bob

Title: Re: More panels!
Post by: LowGear on July 25, 2018, 01:56:52 PM
Quote
Sounds like a crock of sh1t to me.

I'm sorry ajaffa1 but your missus is correct about the magic of dryers.  Well, except the fabric conditioner which falls outside my zone of understanding as well.  At 40 C it should take about 15 minutes to dry an elephant. 

The big question is what were you using for clean clothes?
Title: Re: More panels!
Post by: BruceM on July 25, 2018, 03:56:53 PM
Computer/projector and lighting (incandescent) are my only electrical load, besides daytime electric cooking. 
I only switch to gas cooking on dark days or nights because I'm in the habit.  I never feel like I'm short on power.
The new inverter will find sunny day uses, but won't be running at night.

I remember now about your wire size problem.  You could still use the panel shorting SSR's to limit PV input if adding loads gets to be a problem.  The Mager brand Chinese one's are about $8 each. You could test this yourself by putting in the Tee connectors for a panel and manually short it on a day when you're getting overvoltage trip outs.  The same voltage relay approach could operate the panel shorting. 

Title: Re: More panels!
Post by: BruceM on July 26, 2018, 01:06:46 AM
I rewound mine 2- 1000 watt inverter transformer secondaries today.  Did the trick nicely, peak voltage range is lowered just enough, I think.  I haven't put the 120 turns of 1/2" heat shrink mylar strip around it...that's a PITA and I'm keeping my options open. :)

I'm going to do a jury rig hookup in my battery bank shed so I can test the well pump, which has it's controller/starter there.  The well pump has a wicked surge current, about 3x running current.  I'll have to see if the Antek 1000 watt transformers are up to it. 

The final hookup will have the transformers in a steel box in a far corner so that when I have to do some troubleshooting I won't get immediately incapacitated.  6 feet makes quite a difference when the field is falling off with the cube of the distance thanks to the use of toroids.

I had a good chuckle at myself this AM.  Last night I thought I could "tighten up" the RMS voltage regulation and would take more samples of the recitified and scaled down to 4V peak AC waveform.  On closer inspection this morning, I found that the ATMega328P (Arduino Uno Processor) is so overtaxed that it's a freaking miracle that with 128 usec between samples that my real time RMS voltage computation works at all.  No way it's sampling right on time, it's more like ''semi-random". The A/D takes 100 usec per sample, and the poor little AVR is timer- interrupting 19 times per 16.67 milliseconds. Some of those are time critical 45usec apart as I'm doing some H-bridge hardware functions in software.  32 bit integer math is tough on an 8 bit processor.  I can't use timer interrupts or A/D interrupts since the main 16 bit timer routine is too time critical.  It does warrant some investigation-  I can imagine how it works as well as it does.

I can live with +-2 volt regulation under load, and +5V no load.  If I was planning on developing this further , with features such as variable frequency and/or 3 phase options I'd need a lot more of a processor. 

I like the looks of the Arduino IDE compatible Teensy LC. It's 32 bit, 48Mhz, fast 12bit A/Ds, much more ram, timers, etc. The power consumption is shockingly low if the data I found is to be believed.




Title: Re: More panels!
Post by: ajaffa1 on July 26, 2018, 10:59:57 PM
Hope you can cook better than I do or there is likely to be a nasty outbreak of botulism.

Glad your wife has been given early release, good luck with the logistics side of things.

Bob

Title: Re: More panels!
Post by: ajaffa1 on July 27, 2018, 11:28:35 PM
Hey Glort, when I was living in the UK I had a kettle that held about 4 liters of water but only boiled one cupful at a time. You put  a cup under the spout and pushed a button, twenty seconds later and the cup was full. Saved an absolute fortune on the power bill. Haven`t seen them for sale in Australia but might have a look on one of the online retailers.

Bob
Title: Re: More panels!
Post by: BruceM on July 28, 2018, 01:41:45 AM
Brilliant idea, Bob. The sales pitch (for the wife) is faster cuppa. 
Title: Re: More panels!
Post by: BruceM on July 28, 2018, 03:30:48 PM
Someone led you astray on criticizing solar hot water performance in winter. While your Sydney sunshine is lower in June, the rest of your winter looks pretty decent for solar - PV or direct hot water.  You do have less hours of sunshine but you still get the 85% vs 15% efficiency boost heating water directly vs PV.  85/15= 5.6 times more area of PV.  If water heating does prove to be a big part of your winter power load, then solar hot water (of the drain back type) might make sense.  It certainly can make sense for space heating as well... it does for my house in a much colder winter climate.
Title: Re: More panels!
Post by: ajaffa1 on July 31, 2018, 09:35:03 AM
Hey Buddy, sorry to hear the missus is still crook. If she is feeling the cold she may have a bit of a fever please check her temperature as post operative infections usually start with a fever. If caught early they are usually easily treated with antibiotics.

On the subject of panels, had a bit of a problem with my solar installation today. My hot water is provided by an electric immersion heater in a 300 ltr pressurized tank. To make the most of our free solar energy we have a timer which is set to heat hot water, during the day, while the sun is shining. The first timer failed less than six months after installation, it was replaced free of charge under the guarantee. The replacement now looks like this:

Very lucky it didn`t burn the house down, if you have one of these cheap pieces of Chinese crap in your distribution board get rid of it before it kills you! Spoke to the installer and he is going to fix the problem and visit a lot of his clients that have a similar unit.

Bob
Title: Re: More panels!
Post by: EdDee on July 31, 2018, 11:14:37 AM
Re cooked timer....

Been there, had that.... What I found was the sparky was using his special "low torque" screwdriver to tighten the terminals... The internal contacts were well within rating, but the things were overheating at the ecternal terminal junctions.... Got out my special heavy duty screwdriver, a 6ft pipe to extend the torque, and then leaned 2x 300lb gorillas on the end to get the terminals nice-n-tite.... Well, not quite, I maybe exaggerated just a wee tiny bit, but you get the idea...

Since then, no more problems... but I do check over ALL the terminal screws in a box that I have been working in every time before I close it.... Saves a lot of expensive smoke in the long run....

Cheers
Ed
Title: Re: More panels!
Post by: ajaffa1 on July 31, 2018, 12:54:30 PM
Spoke to my mate who`s a sparky, he tells me that these cheap units are sh1t and should only be used to trigger a power relay that CAN cope with the load. The draw on the heater element is just shy of 15 amps and the timer is rated at 15 amps, so at it`s limit and will burn out in no time.  I`ll wait till the installer replaces the timer and then fit a power relay after it. May be illegal for me to mess with the electrics but clearly I know how to do it and they don`t and it`s my bloody house that could have burned down! >:(

Very glad to hear you wife is making a good recovery Glort. Keep up the good work with the nursing.

Bob
Title: Re: More panels!
Post by: ajaffa1 on August 14, 2018, 12:00:02 PM
Hey Glort, one thing I have found is that it is much cheaper to keep a home cold/warm than to heat it or cool it once it has become uncomfortable. Hook the AC to your solar and use it as much as possible during the day, much cheaper to come home to a cold/warm house than to come home to a hot/cold one and try to heat/cool it down using imported electricity when it gets dark. Ditto hot water, which should never be heated at night. I have also found that when boiling the kettle, it is a very good idea to put any excess hot water into a thermos flask. Your next cuppa costs nothing.

Bob
Title: Re: More panels!
Post by: BruceM on August 29, 2018, 03:36:44 PM
Game cameras with IR motion detector is what you want, I think.  I've not used them but was considering them when a meth junkie was crowbarring into my secure mailbox once a week.  They eventually caught the two women who had been raiding all the rural mailboxes in the area for half a year.  The county sheriffs have zero hidden camera gear.  Apparently too busy with petty drug busts to be bothered with preventing/solving thefts.

Title: Re: More panels!
Post by: BruceM on August 29, 2018, 05:16:35 PM
In small town, very rural US, the police have been militarized by federal funds, and even in a tiny town of 5000 actually have heavily armed, black suited SWAT team that look like Gestapo to me. All part of the "war on drugs", while big pharma profits obscenely every day by creating new opioid addicts.

I know a guy who lives in town who had long hair, surrounded by Mormon neighbors who didn't like that. His wife is an artist and makes stone statues of dragons that are very cool. The local Mormon Justice signed a warrant based on his electric power bill being $15 more than his neighbors(!), for suspected pot growing. A dozen man SWAT team with automatic weapons smashed in his door with a RAM, trashed his home and found...absolutely nothing. A year later he was still trying to get reimbursed for the damages.

Last year, my county rolled out their big SWAT team to make a big drug bust- on an elderly man with terminal cancer living in a rural area outside town who was licensed to grow his own pot in a walled in, secure area per the law.  He moved there to pursue his treatment. His son and daughter in law were his caretakers and were also licensed to grow, but the daughter in law's license was recently expired. So there were a few plants too many (cancer treatment takes a lot of pot) given her expired license so they seized all the plants, and threw the son in jail and pressed charges against them.  There was no evidence or even suggestion that they were selling pot. 

The county wants more tax money for more officers. They want more money for more prisoners, the bulk of which are there for petty drug offenses or waiting for trial for same.
It sure doesn't remind me of Mayberry, RFD. 


 










Title: Re: More panels!
Post by: mike90045 on August 30, 2018, 04:25:43 AM
Calling 911 in rural California?
Danger might be close, but the law can be hours away
  ( 911 is the USA emergency number that goes to the dispatch center for
fire, sheriff or traffic control )

Most of inland and California north of San Francisco, is rural.  My area has 1 patrol sheriff officer to cover about 1,000 square miles.

https://www.sacbee.com/latest-news/article215453050.html

excerpt
"Kristine Constantino, had dialed 911 from her cabin five hours northwest of Sacramento and hung up. The closest deputy was en route from the county seat of Weaverville, 97 miles away. But the drive — through rugged forest and over steep passes — would take almost three hours"