Cool Off

It's useless to keep heating the tank of your water heater if there's no one in the house to use it. Set your water heater to the lowest temperature—or to the "vacation" setting—and save up to $7.50 on energy costs for a two-week vacation.

You'll also save 8 therms of natural gas or 150 kilowatt-hours of energy—keeping up to 100 pounds or more of CO2 out of the atmosphere.