Man, I almost forgot about this. My brother had sent me a link to a web site with very useful "Java based" calculators. Now the author, Chuck Wright calls them "calculators to figure out conservation and renewable energy". I call them "Green" calculators.
There is one that figures out your personal carbon foot print. Then he has others to calculate how insulation saves you money and how it wastes if you don't. There is even a calculator to help you size a PV system.
For you DIYers out there, this may be very helpful.
Browse his site there is other Green information there also.
I'll add a permanent link on the side for future reference.
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