PV Gap

Larry Said:

How much real kWH can I expect from a 4kw CEC-AC solar system?

We Answered:

The industry figures in about 30% system losses from the rated output of the system. Your location determines the number of sun hours, or the equivalent hours of the standard test condition, let's use 4.5 for this example, that's fairly average. You would multiply the rated output of 4kW x 4.5 average sun hours x 70% = 12.6kwh a day. Multiply that by 30 days, you average 378kwh a month. Compare that with your monthly bill from the electric company, and you can see what percentage you'd be offsetting.

P.S. A great bang for the buck is solar water heating. Much lower cost of entry, and they are 85% efficient instead of solar electric's 20% efficiency. Depending on the rebates in your area, and how you currently heat your water, you can have a payback in half the time as solar electric.