Federal tax incentives are better than ever now for home improvements that conserve energy. The Stimulus package offers some great tax advantages for work you have done to save energy (and money). The Federal Weatherization Assistance Program allows for up to $6,500 to spent on energy saving improvements. Tax credits up to $1,500 are available for energy saving improvements are Energy Star qualified including; insulation, windows and doors, roofing, HVAC and solar systems.

For a great explanation and chart on what is covered take a look at the Energy Star website