Solar Electricity is here for the longterm.   But one of the more difficult aspects of understanding solar, is determining the costs of a solar system vs. the benefits a homeowner gains when purchasing a system.

In this article, we will explain how you can produce $100 worth of electricity from your own home solar system.  And we will give details on how much the solar electric system would cost to produce that same amount of electricity.

To start, we need to choose a location in the United States to be working with.  This is important, because nearly every location has a unique amount of sunlight hours per year, and different locations also have different prices for electricity.  Another varialbe that should be taken into consideration are the current solar rebates that may or may not exist as this will affect the systems costs.(For this example, we will not take into consideration any rebates or tax incentives for solar)

Solar Example:

• Location:  San Francisco, California
• Average sunlight hours per day per year = 5.2
• Average cost per kilo watt hour of electricity = $.23

So, first we need to determine how many kilo watt hours equal $100

• $100/.23= 435 kwh equals $100

Next, we need to figure out what size solar electric system is necessary

• 435 kwh would equal 435/30= 14.5 kwh per day
• 14.5 kwh/day  divided by the average sun hours per day of 5.2 (14.5/5.2)=2.79kwh

So, 2.79 kwh AC need to be produced during each of the 5.2 average sunlight hours

Next, all we need to do is bring the 2.79 which is an Alternating Current number to DC and then we are finished. Since there is an energy loss going from DC to AC, the actual DC number will be about 18% larger than the AC number.

• 2.79DC(1.18)= 3.29 kW solar system

So, in review, it looks like a 3.29 kW DC solar electric system would be able to produce about $100 of electricity per month for someone in San Francisco, CA.

That would be about a 20 panel solar system and would be roughly 300 sq. feet of solar panels.