2009 August | Solar energy

solar water heater panels

Posted August 29, 2009 By admin and has no comments yet.

solar water heater panels
How many solar panels (PV) for a 1500 sqft off grid home?

We use about 400 to 500 kwh per month. We have a tv, computer,microwave, and of course fride, washer/dryer, and back up water heater. (solar water heater is the main one)

Also how much would such a system cost, including batteries and inverters? Rough estimate okay.
I try to use very little energy, and those are the figures on our current electic bills

I use about 500 kWh a month and have a 1600 sqft home. It is two years old.

500 kwh divided by 30 days is 16.6 kwh a day. I don’t know where you live so I can’t say how many peak sun hours you get so lets just use five.

16.6 divided by 5 = 3.3 kwh in solar modules. You said the home was off grid so $30,263.70 for parts. Add in 10% to 15% for the install and you got it .

Really there is no way to know without asking you a lot of questions.

What is the total wattage that will be on the system at any one time.. (tv set, freezer, coffee pot and hair drier and a few lights) that will tell you how big of an inverter you need. Then you will need a battery bank that will only be drained by 50% by the end of the day before re-charging. Which you can find because you know you use 16.6 kWh per day. 16.6 divided by 48 volts battery bank is 345 amp hours in battery power plus like said above you need to double that so 700 AH should do it.

There is still more to it because you need to make sure that the 3.3 kWh in solar power will give you a 5% to 10% rate of charge. At 48 volts you would have about 68 amps so you are close to 10% so all is good so far.

If you plan to do it all your self you should start out by buying the parts for a small system and teach yourself all about it. Or talk to a dealer.

Here is a good info page to help you out.

http://www.oynot.com/solar-info.html

And here is a price list of complete systems. http://www.oynot.com/solar-grid-tie-backup-by-array-size.html

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