There are also proposals for a permanent research and development tax credit, temporary expensing of business investment, and payroll tax holidays.

FORBES: Understanding the Laffer Curve

Federal tax credit: The federal government offers a 30% investment tax credit on the cost of the system after rebates. (The credit is higher in Denver, for example, because there is no state or utility rebate.) To claim the full credit, your tax bill must be bigger than the credit.

WSJ: The Economics of Solar Power for Your Home

The Tax Reform Act of 1986 basically cleaned out bloated tax benefits, like the Investment Tax Credit, as a way to generate enough revenue to allow for a significant lowering of marginal tax rates.

FORBES: Connect