So, you took the $1,500 credit in 2009? Are you eligible in 2010. In a word, “no” — but there is one exception.

$1,500 is the maximum you can claim for all of the efficiency measures combined over the two-year 2009-2010 period; you can purchase up to $5,000 worth of products over the two years and get 30% or $1,500 as a tax credit. If you get the full $1,500 tax credit in 2009, you are not eligible for a tax credit on these products in 2010.

The credits for products subject to the $1,500 limit are only available for primary existing residences and only through 2010. The maximum does not apply to geothermal heat pumps, solar energy systems, wind energy systems, and fuel cells, which have no upper limit and are “products eligible for tax credits through 2016.” You can receive both the tax credit capped at $1,500 AND the tax credit for products with no upper limit. Visit Energy Star’s FAQs for more information on tax credit amounts.

The credits are nonrefundable; that is, the credits are only available to the extent you have a tax liability. For 2010, the credits for home energy improvement products eligible through 2010 may be limited if you are subject to the Alternative Minimum Tax (AMT).