Results interesting on the TVA's energy efficient home program

This mornings article in the Tennessean describes the results that the TVA is getting doing research on energy efficient home. Going so far as to put solar panels on homes among other upgrades, the energy cost savings are significant, but the up front costs are significant too.  One has to consider the pay back period on such a big investment.  The fact is that big energy savings can be achieved without big costs, particularly to older and existing homes.  Caulking, programmable thermostats, and weather stripping for example are all affordable and offer big saving.  So, read the article here to see what you think.