Tax credits are available for many types of home improvements including adding insulation, replacing windows, and purchasing high efficiency heating and cooling equipment. The maximum amount of homeowner credit for all improvements combined is $500 during the two year period of the tax credit. This tax credit applies to improvements made to your primary residence from January 1, 2006 through December 31, 2007. Federal tax credits are also available for hybrid gasoline-electric, diesel, battery-electric, alternative fuel, and fuel cell vehicles as well as for solar water heating systems, solar photovoltaic systems, and fuel cells.