I have half a dozen free computer programs to help people save energy on my new website:
Bar X Software
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There are programs for all skill levels, from the homeowner to the experienced engineer. The novice programs do the same robust calculations but have a simpler menu driven front end. All the programs have a single screen and are quite easy to use and understand.I hope you get a chance to visit ~ and learn how you can save LOTS on your utility bills, at home or at work!!