PV Gap

Audrey Said:

How do I figure out how much Solar Energy I will need to convert my house to solar energy?

We Answered:

Yes, you need to look at your annual electrical usage. Not the dollar amount but the KWH used. Then you need to know what your peak usage has been. (the highest month) It would also be good to know what the usage is during the month with the least available sunlight (insolation) Last you need to guess how your future usage may increase. Using an electric car or electric heating will reduce the payback period. You may wish to add one of these options in the future and should add it in now.

Then you want to determine how much of the usage you want to cover with solar panels. You may wish to cover 100% of your needs 80% of the time and the balance you will get from a grid connection. Alternatively you may wish to cover 120% of your needs 100% of the time and also invest in a battery backup system. The more coverage you have the more expensive the system will be. A grid connection will be cheaper than a system that has a battery back up.

Once you have the amount of capacity required you can begin to shop for available panels. Not all are created equally. There are different efficiencies. A lower efficiency will mean that you will need to install more area in panels (need more solar energy.) But basically you will be working in Watts (energy) and KWH (power.)