Under the American Recovery and Reinvestment Act of 2009 and other more recent legislation, tax credits can be claimed by homeowners who install energy-efficient products, including:
Geothermal: An uncapped 30-percent tax credit for residential geothermal heat pump installations through 2016. REHAU's geothermal system qualifies under this program.
Windows and Doors: Claim a tax credit for the purchase of windows, doors and skylights that meet ENERGY STAR program requirements. Many REHAU window and door designs are eligible.
More details available at these sites:
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