Many of the energy efficiency tax credits are limited to $1,500 combined total for 2009 and 2010. The $1,500 maximum tax credit covers insulation, windows & doors, roofs, HVAC, biomass stoves, and non-solar water heaters.
Improvements not affected by the $1,500 cap include:
* geothermal heat pumps
* solar water heaters
* solar energy systems
* small wind energy systems
* fuel cells (up to $500 per .5 kW of power capacity)