To qualify for PSNC's $100 rebate for natural gas furnaces, you'll need to purchase a system that is 90 percent efficient or higher. The rebate will be given as a credit on your natural gas bill. Hang on to all of your installation documentation and use it to help you fill out the rebate application form.

You may still want to invest in a 95 percent efficient system because not only will it save you a lot of money on your utility bills every winter, but you may also qualify for the federal residential energy income tax credit. The credit is equal to 30 percent of the equipment and installation costs for up to $1,500. To qualify, the furnace must be installed on your primary U.S. home.

Also, Piedmont Natural Gas offers $300 rebates for new energy efficient gas furnace installations in North Carolina homes. You must be a Piedmont Natural Gas customer to apply.