In the bit of research I have done into battery's, forkliftpacks are by FAR the best bang for the buck.
I contacted one company and they were most helpful and happy for their product to be used this way. Reckoned it was a lot easier on them than being used as they were intended... in forklifts. I can well see why. Stationary setup with probably a much lower DOD than people would do with mobile application.
The people I spoke to said they would gaurantee their packs for 5 Years IF the automatic watering system was fitted. For $200, sounded OK to me.
They said that in the systems they had done before, 10 years was pretty much a minimum if they were in a really harsh climate or really flogged with deeper than usual discharges. they admitted they weren't the lightest or most compact or anything else new and trendy but they were a tried and proven technology that was not the most reliable and the cheapest storage available on a watt per $ basis.
I would like to have a go at one of those DIY powerwalls with the 18650 laptop batteries. You'd need a DAMN good supply of them though.
I am watching a couple of YT channels and my question of how do you know even after all the testing and conditioning the things won't go belly up in short order. Seems the answer is you don't and several of the people on the channels I'm watching have had this happen. Not the end of the world I spose but would be interesting to see how many times this happens over a few years. Easy enough to swap them out but if you are doing it every few months, could get to be bit of a drag.
One thing is for sure, these guy are getting some SERIOUS storage going. A tesla battery holds 10Kwh. These guys are starting with 20KW, going to 50 and after that seems to be easy to go to 80 and 100KWh. One guy has just hooked up 120Kwh. That is a LOT of energy storage and several tens of thousands of batteries he's mucked around with to get his capacity that high.
I am told there are other and better sites but i have found the PVWATTS site very helpful and informative in planning out the positioning of my setup. It tells you the amount of power panels will generate in different locations at different angles and orientations. Very hand when you are not sure if the south ( worst in the northern hemisphere) roof which is very flat is better than the west roof at the supposed better angle and what their outputs will be at different times of the year. For me the near flat south side is better but I have never come across a site yet that would tell you that.
Like about everything else I have learned through the net, the approved practices and advise taken as the correct gospel have holes you could drive a truck through. Sideways.
The " Optimal" angle of latitude for instance is very often not the best angle at all! I was trying to work out how best to mount my panels and what I was going to build my mountings with to get them to the correct angle. I decided to throw them on the shed roof which is 5 and 13o pitch and I wondered how much that would kill my generation. Much to my surprise I found having the things near flat yelded me significantly more power over the summer from nov to Feb than the " ideal" angle would. The over all for the year laying them direct on the shed rood was so little that there was no way to justify the cost, effort and risk of having the panels kicked up a foot at one end rather than lying them flat on the roof and much less susceptible to the high winds we get here.
Came back to my old solar efficiency rule, cheaper and better to add generally a couple of panels to the ones you have to get better production than try and make them more efficient. The gains are generally small with optimising, the costs are usually high and no improvement in making an array more efficient works as well as just having more panels on a cloudy day.
That site and I imagine similar give you the opportunity to crunch numbers and see what would be best and moreso, suit YOUR ( or your neighbours) needs best.
The other ones I'd recommend looking at but are a bit variable and tend to err on the side of overcaution are the cable length/ size/ power calculators.
If these panels are not going above where the power will be used and there will be a decent cable run, these are very helpful even if conservative.
I have changed my plans to a degree with my setup. Going to locate the panels closer to where I want the output rather than the best yield possible. Again, for what i'm buying panels for ( and geez I'm slipping, haven't bought any in almost a fortnight!) it's cheaper to throw a few more on the less than optimal roof than run the required cable to where they would make a bit more power. I have a heap of roof so no problem space wise. If I covered the roof in panels, I'd have to have the cable back to the power pole upgraded..... and they might have something to say about that!
I'm going to invest in a roll of 6mm. won't need it all but a sparky mate uses it and say he'll buy whatever I have left over. Then again, probably end up using more than I damn well think!
I am going to cheat a bit and put one solar array on the water heater circuit. I have moved that from the off peak already and been testing with my voltage monitor relay to kick it in. had a couple of days where it was cloudy and I don't think it got any juice but the system is a 400L which is well beyond our needs and stays hot enough for about 3 days showers etc .
That is a 20A circuit already and I will tap into it near the heater anyway. When the solar is generating and the heater kicks in, the load on the wiring will be minimal because most of the power will go about 3 ft to the heater and not all the way back to the board. When the heater isn't active there will be plenty of headroom for the solar array.
It's getting easier to mount all the panels than it is to run the power they generate somewhere. I am looking forward to a very cosy and cheap winter though. ironically it will be cheaper to run several fan heaters than it will be to run the reverse cycle... not to say we won't use that as the main heating to get the place up to temp then use the fan heaters to maintain it in the rooms we are in.
I have learned a lot with solar and I find it very fun and enjoyable. There is a fair bit to take on board but it is all fairly logical and straight forward. I'd say rely more on your own findings and don't put an over amount of weight on what commercial sites say but you can rely on the calculaors which tell a different story with the numbers plugged in to what the sites, even the DIY ones tell you. Might be a case of trying to be all things to all people but certainly paying attention to YOUR circumstances gives far better results that worrying about what best suits other people 10K km away in a totally different climate.
One tip i'd give is when dealing with used stuff, pay attention to connectors. I have bought several systems and none of them came with the inverter AC connector and they can be difficult and expensive to get. I don't bother with them now. I just open up the inverter, take the connector away and run heavy cable through a grommet or strain relief right to the board. Probably Kills their IP rating but I don't want them out in the weather anyway.
Other thing is tell your neighbour to order about 20 Pair of MC4 connectors through flea bay. This the last ones I got the other week were about .70c pair. at places like jaycar, they want $12:50 for the bastards! I can buy a whole bag of them sent to my lettterbox for $15 and I have not had any trouble with them yet.
Often the slack arses that take the old panels off jus chop the wires and the last lot I had they must have just reefed on them till they seperated one way or the other. I found a couple of panels which tested OK but the array was open circuit. Traced that back to the conductor being pulled too far back in the connector housing and failing to meet up with the opposite conductor. Couple I undid and reseated them correctly, another couple were chop and replace jobs. Pays to have those Mc4's on hand. And get some of those little plastic connector tools as well. Some of them can be near impossible to disconnect without them. Dollar odd each on fleabay.
I'm sure your updates on the project will make for interesting and satisfying reading and look forward to it. Don't forget lotsa pics! :0)
