As of early 2009 (as a part of President Obama's American Recovery and Reinvestment Tax Act of 2009) there is a tax credit up to $1500, or 30 percent, for the cost of the products falling within a criteria for energy efficiency. Many windows, glass doors and skylights will have an "ENERGY STAR" sticker to verify that your purchase is a 'green product' and will qualify for the tax credit. If not, look to see if there is a manufacturer certification statement before checking out at the register. Your local retailer should have more information on how to submit your receipts for the tax credit. As with any tax question we suggest speaking with a CPA prior to making a decision to upgrade. You can also visit the Energy Star website for more information.