Quote:A watt is a unit of energy per time, so a 5,000 watt AC unit will require 5,000 watts of solar panels == 20 panels. Since AC usage is highest when the sun is beating down on the roof, one probably wouldn't need much more than that. Offsetting the AC is probably the 2nd best use of solar, after heating water. The water is heated directly from sunlight, so conversion to electricity is not needed in that case, which makes it more efficient.


It's still more expensive than electricity delivered by the power company, but if it makes someone feel good about being 'green' then that has value too.

Two things our appliances are measured in watts but power is billed in kilowatts that's the reason for conversions when trying to figure out how much solar energy one needs.


Second the ac unit is 5000 watts per hour of peak usage so you have to multiply that 5000 watts times the amount of hours in peak use. In Florida it's easily 16 hours during the summer. To figure out how many panels you need to run that ac all day you'll néed to multiply each panel by 4 hours of peak solar activity and then by .85 to compensate for some loss of electricity in conversion from harnessing to production.


You are correct solar water heating tanks are more effiecent and require less energy but if you want hot water at night or during cloudy days you'll need additional heat generates by electricity

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