In an attempt to stimulate development of U.S. solar projects, Congress has approved a one-year extension on its 30% solar tax credit (no credit cap for business entities; see PDF for details). It is not known whether this credit will be in effect beyond the 2007 tax year (2007 ends on December 31, 2007 for calendar-year taxpayers). Although the size of the U.S. solar market is growing, tax credits help to encourage capital investment in solar projects. A longer extension (10 years or more) would incentivize investors to add more solar projects to their portfolio. A solar tax credit also provides some breathing room for green real estate builders and developers. If home prices level out in 2007 as expected, builders and developers of green projects can use the solar tax credit to lower tax bills and take the sting off an anticipated lower net margin.