If you heat with electricity and live where electrical rates are lower at off-peak hours, an electrical thermal storage heater could save you money.

This kind of heater consists of a well-insulated shell filled with ceramic bricks that efficiently absorb and store heat. The bricks heat up during hours when power rates are low, then release the heat, using a blower, when the rate rises, potentially saving you hundreds of dollars a year.

Al Takle, national sales manager for Steffes Corp., says the units only make sense where rates dip for part of the day. Where’s that? He listed:

• Arizona
• Colorado
• Indiana
• Maine
• Minnesota
• New Jersey
• New Mexico
• Pennsylvania
• Wisconsin
• Wyoming

Thermal storage heaters sit on the floor and are about 12 inches deep, 24 inches high, and 30 to 60 inches long. They require only a little clearance on sides and the top, so you can easily build them into bookcases or window seats. Costs range from $1,200 (for a small bedroom or office) to $2,200 (for a 1,000-square-foot, open living room and kitchen space), or $2-$12 per square foot of living area.