Author Topic: More panels!  (Read 8913 times)

glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #45 on: March 14, 2018, 10:15:44 AM »

Would the good management you have in mind manage the cells individually or just in the packs?

Got to admit, this balancing things seems a counter productive to me. If I have a group of batteries all connected together, I would assume they would automatic balance themselves in the higher ones charging the lower ones etc. Obviously not.

I have my reservations about lithium. As usual it's hard to get a clear picture of reality but it seems it is a limited commodity and that's never a good thing to base a technology on.  Then again, we are told Oil is running out but notice that's only ever rammed down your throat when the price goes up? All the rest of the time seems there is a limitless supply and plenty of wells to go round. A suspicious person ( unlike me) might just think that's a diversion to make people thankful they can get it at all  and not notice how they are being bent over and screwed.

Tesla has supposedly been busy developing another battery about 3 times the size of the 18650.  Due to those mathematical anomaly''s that go with needing about 6x 1/2" pipes to flow the same as a single 1" pipe, they can increase the size of the cell 3x but get something like 5x the energy density in the same over all pack size.  They are supposedly going to or have gone to this new size in the model 3 or the upcoming Roadster.... if they are still around that long.

It is interesting that they are still using "cells" as we know them rather than the flat type Lipo packs.  A lot has to do with packaging and placement but still.  I would assume it to be easier to get more density in a given are with square objects than round ones. Then again, they may be counting on the dead air space for cooling.

From what I have seen, It will be a very long time before the good ol lead acid battery becomes more expensive than anything else for stationary use. 

Making power now is relatively cheap with panels but storing it, that's one hell of an expensive handbrake to over come.  Maybe.
I once read a piece on Cold Fusion and it's possibilities. The writer concluded that it was not only possible it had been developed in some Gubbermint Skunkworks, but Highly likley.  The apparent conspiracy theory turned around when the guy explained why he thought it would never see the light of day.
Balance of power.

Basicaly you have all these countries will huge numbers of people they are usually very poor and have long histories of war. If suddenly clen, cheap, readily available power were available to them, the first thing they would so would be manufacture the weapons they could not afford now. They could mobilise great military power with personell in the many millions and there would be basicaly no stopping them.
Thats a very brief and oversimplified explanation but essential the Crux of the matter.  Energy and it's cost is what keeps the rich countries rich and the poor ones not.  Give everyone affordable energy and the tables start turning and that not what those at the top of the heap want

I wonder if battery power tech is being withheld in the same way?  There are a lot of vested interests in power, many of the worlds largest companies in fact and I'm pretty sure they are not going to be Doing a Kodak and rushing into a technology that will put them out of business for a very huge chunk of their market. If the average household could cover it's roof in panels, get a battery that would last many years with no maintence and at low cost, Imagine what that would do to the power industry. Not just power companies but people like GE who make nuke reactors, turbine generators, transformers and power conditioning equipment, switchgear etc.
Industry would also bail into self sufficency and the downturn for large traditional markets would be catastrophic for those in the game now.

There would also be a loss of the big brother factor which is being pushed so hard these days with the likes of smart meters and appliances.

BruceM

  • Hero Member
  • *****
  • Posts: 2592
    • View Profile
Re: More panels!
« Reply #46 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.   











glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #47 on: March 15, 2018, 12:43:37 AM »

Geez Bruce, I'm surprised at you!!!

You don't believe that I picked up a tin can by the side of the road, urinated in it, attached a couple of old bits of fencing wire to it, sat it beside the carb so it could inhale the orgone energy that lets the car burn the 70% of fuel normally wasted and the vehicle suddenly made 1000Hp, 2500Ftlb of torque and got 176 MPG up a mountain side at 90 Mph with a 5 ton trailer on the back??

Geez, loads of other people I told about it on the net did!  Think I'll have to find myself another forum where people aren't so mean and offensive as to not believe every stup.... helpful thing I say with this stuff!
 :laugh:

Wait till I show you my free energy machine that is a flywheel with a bunch of pulleys, belts and shafts that you spin up and then can connect your whole house to and power it forever@
I put a YT Vid of that up and you would be amazed how many  Idi.... open minded Crac.... people complimented me on my achievement and want to buy it.  Unfortunately now I'm in hiding because the gubbermint ( which Gubbermint I don't know) want to kill me like they did with all the other Nutca.... inventors.

Look Bruce, this stuff is real easy to see the potential in if you look at it the right way.
You just have to be open Minded and forget about restrictive things like Physics, and mathematics and science and Logic, common sense, proven formulas rules and laws of engineering.  Get that out your head!
IF you can put Fac... limitations behind you and start thinking in terms of the tooth fairy, Santa Claus, Mythical unicorns, the man on the moon and other such rubbi.... open mindedness, You'll see it's all perfectly possible.
I have observed from the people that can see past these worldly limitations,  Alcohol, LSD, Crack, Pot, vallium, Cocaine, sniffing glue and petrol, heatstroke, deyhyration, loss of blood and other Mind altering substances and the abuse thereof, can help one greatly in seeing the potential and understanding how these things work with perfect clarity!

I hope you will take a more open minded look in the future so you too can see the great Bullsh.... promise these things hold.

 ;D


BruceM

  • Hero Member
  • *****
  • Posts: 2592
    • View Profile
Re: More panels!
« Reply #48 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. 


glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #49 on: March 17, 2018, 10:34:25 AM »

Did a deal on another used solar setup today.

3 Kw of little 170W panels, 3.6Kw inverter, usual isolators, racking and crap. Didn't take long to bargain the guy down on this one either.
It's all getting a bit too easy and I managed to put my bargaining skills to work again yesterday.
Getting a lot of this racking and there is no market for it so I'll either build another pergola with it or cash it in for scrap.

Went furniture shopping with the Mrs yesterday.  $11.5+K worth of stuff went out, delivered for $8k. Discovered this morning they left a cabinet worth $900 off the order.
Rang and they said they hadn't priced that in. Said we had spoken about it, I'd spent the budget and it was all or nothing.  That started a 20 min to and fro with them finally falling over . I was glad it was a fight and I didn't think I 'd get it actually but if they hadn't fought me over it, I would know I left too much on the plate in the deal.
I then really went for broke and said I'd take a 2nd cabinet as well. That cheered them up..... Until I started bargaining them on that having seen the cost price on it when we were in the shop on the computer.  Well I did leave $44 in it for them. Seems they work on 40% average markup. Some was 20% off already and then I bargained on the total. Spose in reality we got even more off than I really counted.

I think the manager who was serving us was pretty happy when she gave us the total. Then I casually sat on the display lounge behind her and said "So what can you do it for all up with delivery?" She said that was the price. I said you are going to have to do a lot better than that.  Lot of painful faces, lots of no way, lots of what if we substitute this for that so in the end, they were happy to give me the price I wanted and get us the hell out the place.

Woman said, " I have been in this company 11 years and I never came across anyone quite like you before."  I said yeah, I know and with a lot of luck, you'll never have to put up with any mongeral pain in the arse like me again!
She laughed and we chatted when the business was done so all good.

As Mrs is almost happy, now, we just have to find a couple of new lounges. Like some we saw already but can't decide which ones. We are going to wait till the other stuff is delivered and I throw a lick of paint around and then go back and terrorise the poor woman at the same place again.
Meanwhile, because she has all this new stuff she wants,  I can go shopping for that new camera lenses, laptop and a few other bits and pieces I want.

If I can turn these panels for what I hope, that will at least put bit of dent in it. Hopefully a lot more will come along I can grab at the right price as well.


glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #50 on: April 11, 2018, 04:34:28 AM »

Started installing some panels on the house today.  I have 9Kw of 240 and 250 panels I want to get up in preparation for our winter and the subsequent heating that will be needed.  So far we are keeping up nicely with about 9kw installed but that has been when the solar radiation has been at it's high point and no it's on the rapid downhill slope. I'm, already noticing in good clear sunshine like today the yield is way down on what it has been.
The weather is unseasonably warm atm, was over 30oC here yesterday when it should have been in low 20's and today supposedly to be cooler is back up in the high 20's.

Putting the panels on the house is a real challenge.
The roof is sloped at 35o and being tin, it's impossible to walk on and not slide off.  I'm working on the part where the verandah is which is much flatter and I can get a row of panels on the bottom line of roof screws and on the flatter section. this is the west side and the north which is the best aspect here is at 35o with no verandah or other " Catch" area should one slip. Not real sure how to go about putting the panels there. I thought about hiring a cherry picker but not sure I could get down to the roof with it anyway. Mate has all the safety harnesses I could borrow but not sure how I could stay tethered and work with it anyway.  I think I'll try and borrow an aluminum ladder, clamp it to the roof on the sheet metal screws and work up from there.
Still seems a challenge handling the 20 Kg panels.

Mate might have some better ideas and tips. there is another huge area at the otehr end of the house on the west side that would be good for probably another 8-10 Kw of panels if I wanted to install extra but that is on the same 35o pitch.
Sure was a lot easier working on the 5 and 13o pitch shed roof that's for sure!

I'm also seeing the house ( and the shed) is becoming far more shaded than I realised.  the weather Cock on the shed is now shading one panel a fair bit  and the lower panels are being shaded on the ends by the eve of the higher pitch of the barn style roof.  I was aware of that when I put them up and thought I had allowed enough backspacing but obviously not.  No big deal, I can easy move them to the outer edge of the roof as there is plenty of space.
Also thinking about adding more panels there and limiting the output as I need to by the wiring with a 2Kw inverter.  With a heap of extra panels, thing should run the full 2 kilo from early morning to late in the afternoon maximizing generation time wise if not ultimate output wise. 
Can't remember what I even have up there atm, have to get up and have a look and then work out what smaller panels I have juggle around for best output.


BruceM

  • Hero Member
  • *****
  • Posts: 2592
    • View Profile
Re: More panels!
« Reply #51 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. 

glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #52 on: April 11, 2018, 07:59:46 AM »

I was pretty much thinking of ladders on the roof. I'll hit the well equipped guy next door up. I know he has some monster thing he's offered me a couple of times but something more manageable might be the way to go.
Also thinking this won't be a one man job. I may not worry about playing with 100V generators, 400V+ solar outputs, 500Kw oil burners and other things people cringe at but I do recognise when I am about of my depth and what a real danger to me is. Falling off that roof is a significant risk and one I'm not keen to take. I'll be only too happy to put on a harness to stop myself falling and ending up in a wheelchair or worse.

I started on the part where the verandah is where I can't slide off but trying to do anything on the pitched part of the roof is very telling.
I'll get more knowledgeable advise of my mate and think this very well through before attempting the north side of the roof with the other 250W array.

Got all the other panels up for the west side, now just to wire them together and screw them down. I'll have to go buy another roll of cable as I'm out atm.  I'm thinking I'll do them in 2 strings and use a common heavy ground wire to save on cable. That's what I did with the small arrays on the south side of the shed and that is working fine. Total capacity of the system will still be well below the max amperage of the wire. I'll use a splitter to have an input into both sides of the inverter.  Some of my inverters have 4 inputs but all go to a common set of terminals inside the inverter itself.
The one I'll put these arrays on have seperate controllers.

I got up on the shed roof and had a look.  That was interesting!
The panels were shading with the crown of the roof as I suspected but geez louise they are Filthy! The set on the bottom 5o roof have a layer of dried dust/ mud on them shading the edge of the last set of cells. It's thick enough I can't see through it at all.  The rest are really dirty but obviously the ones on the 13o pitch are better. 
I moved the lower set further to the edge of the roof but they may need to be moved more which will mean I have to extend the wiring. As the winter comes on I think the sun will get lower and they may have to go right to the edge. there is one spot where I tree I have cut back has obviously some birds roosting and there is a mountain of bird crap there. I have cut the tree back far as I can standing on teh shed roof with my pole saw so it will be tricky from here.  Might have to get a cherry picker in and take the top out of some of these damn trees..

I noticed another one I cut back early on has sprouted with great gusto and is probably at a height where it is going to be shading the panels on that side for too long in the monings.  Looks like that is going to need another and shorter haircut still. WTF was I thinking moving onto property? Work is getting away from me and I'm going flat out.

 I am thinking now about reverse pitching the lower panels on the south side of the shed.  The roof on that side angles the wrong way but at only 5o I wasn't worried.  Seeing the dirt build up, I'm now thinking about using the heaps of racking I have picked up and angling the lower edge back to the sun.  If I do that they will be pretty visible where as now lying flat they aren't so noticeable.

Might leave it till I get these others up as I might have so much power I don't need to worry.  The dirt is going to annoy me though. It has been VERY dry here and winter is drier still so I'll get up and clean them and see how they go from there.

I always thought this thing about cleaning panels I see advertised was a load of crock but I can see on low pitched roofs it may be well worth while.
Spose if you get someone in and they charge $100, that would be a LOT of power to make up over and above just leaving the things as is and waiting for the rain.  Getting a hose and a broom yourself and spending 10 Min may be a lot more worthwhile however and just squirting the hose up there may be effective as well.
 
It's certainly a learning curve this DIY solar but an enjoyable one.

BruceM

  • Hero Member
  • *****
  • Posts: 2592
    • View Profile
Re: More panels!
« Reply #53 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. 

oldgoat

  • Full Member
  • ***
  • Posts: 109
    • View Profile
Re: More panels!
« Reply #54 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.

glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #55 on: April 12, 2018, 04:19:00 PM »

I think the angle has a lot to do with the amount of dirt the panels hold. I can see the difference between the ones at 13o  which is still pretty shallow and the ones at 5o which are virtually flat.

There are heavy Dew's forming at night here now and I think there may be just enough condensation on the panels to move the dust down where it puddles on the edge of the 50 panels where there would be enough slope to allow it to run right off on the steeper ones.

The 5o's will have to be cleaned as the buildup is causing a definite shadowing rather than just a bit of a reduction in light transmission.

I didn't see any increase in that lower array output today. The numbers were precisely the same on all 4 arrays as yesterday. Given the panels were shadowing on the top edge and now aren't, the shadowing caused by the dirt buildup must be significant.  I estimate I am looking around 700W over what I would expect to see.

I will try and get up there early tomorrow and give them a clean and see what difference there is with them.  I'm quite sure there will be a noticeable one if the day is the same.

Other job will be to finish mounting and wiring the other array on the house. that went no where today as I got caught up in other things and then a friend dropped by for a good while.  I couldn't have finished it anyway as I need to go buy another roll of cable and couldn't get out.

glort

  • Hero Member
  • *****
  • Posts: 2775
    • View Profile
Re: More panels!
« Reply #56 on: April 15, 2018, 05:42:09 AM »

Finished mounting and wiring up the latest 4Kw array yesterday and got it commissioned. Chugging along at between 2.5 and 3 Kw which isn't bad considering the time of year and orientation.

Neighbour next door saw me up on the roof and said there wouldn't be any need to mount them there, they wouldn't blow off lying flat on the roof.
I showed him the caluking gun and explained I was removing a roof screw, putting caluk whee it came from and screwing it back down with a proper solar bracket clamping  every panel down.

Said I rather take an extra hour to do that than lie in bed on a windy night wondering how many would be there in the morning.
Didn't take long for my investment to pay off. Last night was the windiest on record for 3 years here with the wind topping 100KMh. NONE of my panels on the house or the shed have moved. Got up to check this morning.  The old bush shed lost a sheet of metal that was overhanging which was no surprise and I was going to redo any how.
panels all OK.

Went out for breakfast and was surprised how clean the front lawn was with the huge gum tree we have that is shedding bark atm.
Once we got onto the street we could see why. It's all up and on the road and footpath. Don't think there will be much more bark dropping for a while, tree has been well cleaned off.

Next thing will be to Mount the 5Kw of 250s on the house. That will take some doing.

Still trying to figure out how to switch High voltage DC current so I can direct power the water heater.  Don't need to do it but I want to learn how to do it and test what it will take over winter to keep us in hot showers.

LowGear

  • Casey
  • Hero Member
  • *****
  • Posts: 2022
  • What? My diesel had fries for lunch?
    • View Profile
Re: More panels!
« Reply #57 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.
NPR Tipper/Dump Truck
Kubota BX 2230
Witte BD Generator
SunnyBoy 6000 + SolarWorld 245

mike90045

  • Mendocino Metro
  • Hero Member
  • *****
  • Posts: 1356
  • Mmmm BBQ
    • View Profile
    • Mikes Solar PV page
Re: More panels!
« Reply #58 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

ajaffa1

  • Hero Member
  • *****
  • Posts: 1213
    • View Profile
Re: More panels!
« Reply #59 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