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i'm using 1800 kilowatts a month for power i am wondering what size wind and solar setup i would need to cover my usage and how large of a battery bank i would need to go off grid
i'm using 1800 kilowatts a month for power i am wondering what size wind and solar setup i would need to cover my usage and how large of a battery bank i would need to go off grid
I assume you mean 1800 KWH of energy. That is 60 KWH per day. The number of panels you will need will depend on where you live which determines how much sun you get and seasonal variations. If you want to be off grid and will only use solar power you need to design for the worst time of year, winter, and will need to look at worse-case scenarios, like a 5 day snow storm. If you plan on say, 3 days of living off a battery with no wind or sun to replenish it, your battery bank will need to provide 3 x 60 = 180kwH of energy. That is an enormous battery bank. Tesla Power Wall is one of the best batteries for storage and it only stores 5 KWH of energy. So you would need 36 of them.
People who are off grid reduce their power usage and also have separate circuits for critical power and discretionary power so they only power the critical stuff off batteries. 60 KWH /day is a lot of energy to be using for an off grid system.
Energy storage cost varies between $300/KWH and about $600/KWH. Lead acid batteries are the cheapest but they don't last long. Lithium is expensive but out lasts lead-acid batteries and can be discharged deeper. There are other exotic storage technologies coming out.
... Tesla Power Wall is one of the best batteries for storage and it only stores 5 KWH of energy. So you would need 36 of them.
I am on solar-power, we have a number of neighbors who are on solar/wind power, and I am active on a couple solar power forums. Within the off-grid community, I have not heard any positive reviews of the Tesla power wall [outside of Tesla marketing].
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... Energy storage cost varies between $300/KWH and about $600/KWH. Lead acid batteries are the cheapest but they don't last long. Lithium is expensive but out lasts lead-acid batteries and can be discharged deeper. There are other exotic storage technologies coming out.
An odd thing I learned as we were making the shift to solar-power, is that as you go through the learning curve and adjust to the lifestyle off-grid homes will burn through their first battery-bank somewhere between 10 and 15 years along. This is regardless of whether you use lead-acid or Lithium. Nickel–Iron batteries (NiFe) last a long time though.
It may be a good idea to go with a cheap battery-bank for your first, then select a more expensive battery for your second time.
Our battery-bank is 48v / 600ah [28,800Wh] and cost us $2,200 [$13.09/Kwh].
I am on solar-power, we have a number of neighbors who are on solar/wind power, and I am active on a couple solar power forums. Within the off-grid community, I have not heard any positive reviews of the Tesla power wall [outside of Tesla marketing].
The reason why you have not heard any good reviews is probably because there aren't any, good or bad. For all the hype from Tesla, they have only made the Power Wall available to a small number of customers. For whatever reason it has been more widely available in Australia. They are now commercially available here on Maui (since September) and I know people who have them and are satisfied.
The complaints I heard were that (a) Lithium is unproven, which is not a complain about the Power Wall product, just about the technology, (b) the bus voltage is 300V while most PV systems run at 48V. This is a legit complaint but higher bus voltages mean less money on fat wires and you are going to convert everything to 110/220 anyway so does it really matter, and (c) that you must hire Solar City technicians to install it and they charge $3k to do that. The latter is no longer true.
Lithium has some very good attributes. It also has much better peak power than lead acid. I think Lithium is good technology but I also think there are better battery manufacturers than Tesla. Like LG Chem, for instance.
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Our battery-bank is 48v / 600ah [28,800Wh] and cost us $2,200 [$13.09/Kwh].
Wow, prices have come down for LA batteries in the last year or so. But even so, you got a good deal. I just looked at Wholesale Solar which has pretty cheap stuff and theirs are about $125/KWH, but closer to $175/KWH once it gets to your door. (I get $78/KWH from your figures).
The cost analysis is really more complicated because the DOD (depth of discharge) of LA is much less than Lithium, and the lifetime in cycles is also different. You really need to compare cost/cycle/KWH of usable storage (not rated storage). I don't know what the most recent figures are for that but it used to be that Lithium came out ahead. But it looks like LA has gotten pretty cheap so maybe it is ahead now.
All that power usage currently is all AC power. As some one mentioned cutting down usage when going off grid.
When I lived off-grid, everything that could be found to run on DC power, was. Lights, TV and players, radio. We have a three way Dometic refrigerator. Runs 110 AC or 12v DC, but also propane. It is extremely efficient on propane. If you plan on leaving for a weekend, it has to be turned down or everything will freeze.
A friend of mine who wanted to learn more about off-grid power systems went to one of those really fancy RV dealers and got 'a tour' as if he was a potential buyer and asked a lot of questions and poked about the onboard 'power plant'. He learned a lot.
The reason why you have not heard any good reviews is probably because there aren't any, good or bad.
A lot of negatives have been written by industry pros.
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... Wow, prices have come down for LA batteries in the last year or so. But even so, you got a good deal. I just looked at Wholesale Solar which has pretty cheap stuff and theirs are about $125/KWH, but closer to $175/KWH once it gets to your door. (I get $78/KWH from your figures).
We got our E-panel from Wholesale Solar, they are great.
All that power usage currently is all AC power. As some one mentioned cutting down usage when going off grid.
When I lived off-grid, everything that could be found to run on DC power, was. Lights, TV and players, radio. We have a three way Dometic refrigerator. Runs 110 AC or 12v DC, but also propane. It is extremely efficient on propane. If you plan on leaving for a weekend, it has to be turned down or everything will freeze.
A friend of mine who wanted to learn more about off-grid power systems went to one of those really fancy RV dealers and got 'a tour' as if he was a potential buyer and asked a lot of questions and poked about the onboard 'power plant'. He learned a lot.
One of our neighbors went off-grid in the '80s. You could not ask for a more simple system, but everything is 12vdc.
It really cuts the cost a lot if you can be happy with 12vdc. Solar power does not have to be expensive.
Unfortunately at the time of our install, our well pump was 240vac. Inverters that make 120/240vac were all 48vdc inverters. Which pushed us into a 48vdc battery-bank [which is more complex than a simple 12vdc battery-bank]. And this pushed us into using 120vac through-out the house, which as everyone knows is a much more expensive system.
ok so what am i gonna need i know i'll need an inverter batteries charge controllers and cables solar panels and a wind turbine and a stand by genset.. am i missing anything..
and i am looking at the trojan batteries what ones would you recomend for power storage. i prefer to go lithium up front than make something cheap that will fail me at the worst time
ok so what am i gonna need i know i'll need an inverter batteries charge controllers and cables solar panels and a wind turbine and a stand by genset.. am i missing anything..
and i am looking at the trojan batteries what ones would you recomend for power storage. i prefer to go lithium up front than make something cheap that will fail me at the worst time
Cables : if you are located anywhere that requires building inspectors, you will need to buy the expensive off-grid power cables. If you have no inspectors you are fine to use 4/0 welding cables, they are cheaper and handle more power but are not building code rated for this purpose.
Windmills need to be 20' higher than any surrounding trees [or higher].
Batteries: there are a lot of opinions on that top. Lead-acid batteries if they are allowed to go dead may freeze and destroy themselves if exposed to cold temps. You never plan to let them go dead, but a leaking faucet, on a -20F night can drain a battery empty. If you have the money than maybe getting Lithium is best.
And this pushed us into using 120vac through-out the house, which as everyone knows is a much more expensive system.
Can you explain this?
If I run 12 VDC in my house, the current that must be carried in the wires is 10x what the current is with 120 VAC. More current means lower gauge wires, means more copper, which is more expensive. Furthermore, I either have to find 12 VDC appliances and electronics, or put a converter in front of each appliance. That does not sound cheap to me. I can see that maybe lighting at 12 VDC is easier but for us, the bulk of our power consumption is the refrigerator, the washer, the dryer, and the water heater. Perhaps you are assuming propane would be used to power those other things?
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and how large of a battery bank i would need to go off grid
