Hello James
Very doable. We need some input from you about what you want to power. The first thing you need to do is a power audit, to document what it is you want to run. No sense putting together a 10kW system if you just have some
LED lights. On the other hand, you're don't get to run power tools on a car battery with a 100W panel. So, first outline WHAT you want to power, and then we can go from there.
I can give you a few generalities that can help you make decisions. First,
people ALWAYS underestimate what their power consumption is, and OVERESTIMATE what their panels can produce. For whatever number you come up with as consumption, then double that, 2X in terms of system size. In terms of what you can produce, multiply however many panels you want by 0.8X to get an honest value for production.
I do NOT recommend you buy an all-inclusive kit that includes solar panels. What I've found is that shipping all that glass is grossly expensive, and you will find far better deals on your
local Craigslist, instead of mail-order. Buy your electronics over the internet. Buy your batteries and panels locally.
There are generally two large classes for solar right now, 12V and grid-tie. The 12V panels have a large price premium because they are for the automotive market. High-voltage grid-tie panels though have lots of production overruns and are being sold dirt-cheap on Craigslist. For example, you can get a 100W 12V panel for about 80-100$ right now, but you can get a 240W 30V grid-tie panel for 55$. But, the high-voltage electronics are more expensive. A 12V only charge controller might cost 40$, whereas the high-voltage controller might cost 130$. So, the smallest systems favor 12V, whereas the larger systems favor higher voltage. I'd say the break-even point is around 200-300W. Once you get over a 300W system size, high voltage is the clear winner in every respect.
More importantly, the really good, sophisticated electronics start at 24V. What does that mean? At 12V, you are pretty much limited to inverters have 1-2 standard 120V NEMA sockets on them. Starting at 24V, you can buy sine-wave inverters that have split-phase 120/240V AC, a built in generator charging pathway, and can be hard-wired directly into your house's main electrical panel. BTW, you will want to have sine-wave power if you want to run anything with an electrical motor, such as your electric drill/saw, refrigerator, ect. Square-wave and Modified Sine-Wave is cheaper, but produces low quality power suitable only for things like
incandescent lights.
I'm gonna recommend you go with 24V. At a minimum, here's what I think you need....
4 6V 225Ah golf-cart batteries, 130$ each
4 240W 30V grid-tie panels, 55$ each. Wire these in two parallel strings producing 8A each at 60V. That's referred to in solar designations as 2S2P, meaning two parallel strings with two panels in series for each string.
1 12/24V Epever MPPT charge controller 130$
1 24V 1500W Sine-wave inverter, Samlex is 520$
Total = 1390$ Throw in some copper wire and fuses/breakers, an call it 1500$ Add a 5000W
gasoline generator costing 500$, so 2000$.
Here's what this system can provide....
Assume you don't want to deplete the batteries more than 50% for prolonged life. What you can get is 225Ah X 24V X 0.5X capacity = 2700Wh or 2.7kWh. Assuming you want the batteries to last 2 days, then 1350Wh per day.
The panels could produce about 85% of the power they are rated for times the number of SunHours you get per day. In winter assume 1000W X 3 SH X 0.85X production = 2550Wh. In summer it would be 1000W X 5SH X 0.85X production = 4250Wh, or 4.25kWh of power.
This is system that can grow as your needs increase. In a few years swap out the golf-cart batteries for larger 400Ah L-16 batteries. Add a third or fourth string of two panels. Add a second or swap out a larger charge controller. Swap out a larger more feature rich inverter.
Good luck!
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