Sunday, August 30, 2009

Income and Savings on PV

30 Aug '09: This calculation is based on the Solar Century method of calculation. To be truly electricity negative, we need to increase the roof installation from 17 to 22 panels.

Working out the income and savings as a percentage of the cost of installation, that is about 8 percent return on the installation. That sure beats leaving it in the bank at half a percent. And if in the future, electricity prices rise, that shortens the payback with every rise. If electricity is 13p/ kWhr now, any guesses for what it will be in 10 years time?

Costs are based on our present annual consumption of 8500 kwhr/annum.
We have also done a calculation with the idea that the Solar earth charging might reduce the annual electricity consumption by 10%. Optimistic? but this is what we shall find out over the next two years.

No comments:

Post a Comment

Comments will be moderated before showing. Please make them relevant to the subject of the posting. Comments which advertise commercial products will usually be deleted.

Popular Posts