Consumers who purchase and install energy-efficient heating and cooling equipment in existing homes can receive a tax credit for 30% of the cost, up to $1,500, for improvements "placed in service" starting January 1, 2009, through December 31, 2010. See EnergyStar.gov's Federal Tax Credits for Energy Efficiency for a complete summary of energy efficiency tax credits available to consumers.
Homeowners who install solar water heaters, geothermal heat pumps and wind energy systems are eligible for a tax credit of up to 30% of the cost, with no caps. Previously, caps on these types of projects ranged from $2,000 to $4,000. These tax credits are available through 2016, and both labor and materials qualify.
