If this was sold back to the grids what would be the profit i would stand to make per day on energy received in these panels? How did you come up with this answer?
This question is too generalized to answer. Are you australia? If so ergon buys the power back at 45cents a KWH which is 3 times what they sell it for.(this is guaranteed for 20years) We have a 2.4kw system and it will take approx 5years to pay itself off. Once carbon trading is in full swing electricity costs are going to go up by 40%, then obviously it will take approx half the time.
Considering capital outlays, such a system might never recover its initial investment. That's why we don't see such small photovoltaic plants popping up around the country - the economic case isn't there. One of the problems is that you would have to sell your electricity wholesale, at a ridiculously low price like 2 cents / kWh. If you were displacing electricity that you would otherwise use, then the financial case is different. Retail electricity could be 20 cents / kWh, 0 times as much, and you could get your money back over time, and start to make a profit. I've assumed you're in the US, with no special feed-in tarrifs. If you're in a country with a premium rate for solar-generated electricity, the business case could be very different.
I'm putting in a $00,000 solar wind project on ST Thomas, Virgin Islands so I have some experience here..... ) depends on where you are...the further north the less efficient the panels are because early morning and late afternoon sun hitting at a great angle isn't anywhere near as good as noon hitting perpendicular..........the US Department of Energy has a solar calculator showing how many hours a day over the year you get enough sunlight to actually run the panels....in the Caribbean the answer is 6 so in Wisconsin you might only get 4 really usable hours a day, Nevada 5, Seattle...forget about it..... 2) the panels I'm putting in are ( roughly) 2 x 3 feet...you would need access around all four sides of a panel...you are NOT going to crawl 35 feet across an array to fix a unit in the middle......so lets say you get 35 panels tall ( 70/2) by 2 wide (3 foot with a 3 foot access area between each row = 72/6) or 420 panels. Each puts out 75 watts at max. So you are cranking out 73,500 watt hours, or 73kW. If your local utility buys back ( net metering ) the juice at, say, 20 cents a kWh, you get $4.75 an hour. If you have 4 usable hours a day x 365 x $4.74 you get back something like $20,000 a year. You pay about $7.00 a watt for a panel. The 75 watt panels are, rounding up, $200. each. Times the 420 panels number is $475,000 dollars. Add in about $2,000 for the inverter to change panel volts to power company volts, and maybe another $20,000 for installation you are looking at $500,000 AT LEAST to put in the system you propose. AT $20,000 a year in sales, its 20-25 years payback. Now, you can play with these numbers up and down but you still get the answer of A LOT of money to buy and build and a LONG time till payback.
