This is courtesy Mary Beth Breckenridge of the Akron Beacon Journal (Akron, Ohio)
Credits are available for these qualifying products: insulation; roofs; heating and cooling equipment; water heaters; exterior doors, including storm doors; exterior windows, including skylights and storm windows; and heating stoves that burn biomass fuels, such as wood pellets or corn.
Credits are also available through 2016 on geotherml heat pumps, small wind turbines and solar energy systems, but these are not common home improvements.
The most understandbale information can be found on the government's Energy Star website at: www.energystar.gov/taxcredits. the Alliance to Save Energy also has helpful information at: www.ase.org/taxcredit.
Hopefully this information can save you some money come tax time.