Ok, let's take the 7819.5 watt hours and round it up to 7820. Let's say you go with a 48 volt nominal system rather than 24.
7820 / 48 = 162.9 amp hours per day
I'm going to multiply that by 1.2 to account for batter losses, wiring losses, and add a safety factor. These numbers can be calculated much more intricately, but I'm not going to do that and 1.2 is a safe number.
162.9 x 1.2 = 195.5 amp hours
Here is Hilo, Hawaii the worst insolation (daily sun hours) if you're using the wrong inclination, etc according to nrel.gov (
http://rredc.nrel.gov/solar/old_data/nsr...state.html) is 2.9 hours per day. We'll use that number to build in additional safety.
We divide 195.5 by 2.9 which equals 67.4 which is your total PV array current in amps.
Now we'd have to choose a solar panel. As an example, I'll use a Sharp NE-165U1 which is 165 watts and is rated at 4.77 amps.
That means we take our 67.4 amp PV array from above and divide it by 4.77 which equals 14.1 or 14 such solar panels in parallel. We aren't done. We take our system voltage of 48 and divide it by the module voltage which is 12. That means we need 4 modules in series. Multiply that by our 14 panels and we find out that we need 56 total panels. Not cheap.
Let's look at battery sizing. We determined our daily amp hours was 195.5. Standard reserve time (how many days of juice your battery bank has) is 3. You can go higher or lower but we'll use 3. So 195.5 x 3 = 586. However, we NEVER want to go below 50% capacity on our batteries or we'll kill them. So we divide the 586 by .5 and get 1173 amp hours. We then choose a battery type. I'll choose a golf cart battery with 225 amp hours of capacity. 1173 divided by 225 = 5.2 which we round up to 6 batteries needed in parallel. Since our nominal voltage is 48 and the battery we chose is 6, then we put 8 batteries in series. We multiply that by our 6 batteries in series and come to the shocking realization that we need 48 golf cart batteries. That means we'd likely go up to L16's which are more expensive but live longer IF you take good care of them.
THIS is why if you're going to be off grid, cutting down on your energy consumption is first and foremost. You need to ditch the guzzlers and get that 7820 watt hour number WAY DOWN.
How much is this going to cost you? I did a QUICK search and a 12kw (you're almost 8kw) system on ebay WITHOUT BATTERIES and a ton of other needed equipment is selling for $41,000:
http://cgi.ebay.com/solar-panel-off-grid...RCH:US:101 and that includes 72 solar panels.
If you want to be off grid and not completely break the bank, you have to change your lifestyle.
Disclaimer: My numbers could be wrong. Always work with a licensed professional. Blah blah blah.
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