Third quarter estimated tax payments are due on September 15.

How to Make Payments. To make your payment, you can use the paper Form 1040-ES or you can use the IRS EFTPS electronic payment system.
Who Needs to Make Payments. For guidelines on who needs to pay estimated tax payments, see the estimated tax payment details.
Payment [...]

Energy efficiency tax credits are for homeowners to improve their house with energy efficient appliances, windows, and other energy saving upgrades.
Most of the improvements must be placed in service January 1, 2009 through December 31, 2010. Here is a summary of the energy efficient upgrades and the tax credit available. For specifications of each, see [...]