This is the time of year when home improvement and hardware stores are beginning to advertise this season's super-duper deals on the newest and most modern thermostatically controlled, ultra energy-efficient electric baseboard heaters. Those with water in them are called portable hydronic units.

They're easy to buy and use, but there's a catch. Both of these types of electric baseboard heaters use electric-resistance heat. And even though they're easy to purchase, install and use, in the long run, dollar for dollar, electric-resistant heating is the least cost efficient source of heat.

If you have a choice, there's another reason to consider gas. If you have an older home, you could be taking a chance by burdening old electric circuitry with a new high-powered electric heater. If electric heating is the only way for you, then at least be sure to install a dedicated circuit to handle the increased electrical load. A small electric-resistance heater will use more power than fifteen average television sets.

Gas-fired heaters are more expensive and slightly more difficult to install than electric baseboard heaters, but in places where gas is available, we recommend the installation of a small gas furnace.

If your home is all electric and there isn't a gas line or propane tank on the property, then there is no choice but to utilize electric heating. In that situation, only highly efficient electrically operated devices should be used.

Spending more on a gas heater than on an electric heater, in the long run, will save money and precious energy at the same time. Natural gas is far less expensive that electricity.

A gas-fired heater doesn't have to be a central heating unit or even a full-sized wall furnace with an expensive exhaust flu that has to be installed through the roof. Small, energy-efficient gas-fired wall-mount heaters can be purchased that will easily heat 400 to 600 square feet. And, they can be installed in a weekend.

The only requirement is that the unit be mounted on the inside of an exterior wall. This is because the exhaust for the unit is on its rear side, so it can exhaust directly to the outside air. No fancy flues or ducting are needed.

First, use the template that comes with the unit to cut a hole in the wallboard between two studs. Next, use the same template again to locate and cut a hole through the exterior wall-covering layer for the exhaust port.

Once the holes have been cut, it's time to run the gas line. This is the hardest part of the job and you might want to hire a plumber to do it. When the gas line is ready, use four screws to mount the unit into the wall and four screws to mount the exhaust flange in place. Remember to use lots of exterior latex caulk between the exhaust flange and the exterior wall surface before attaching the flange. If you cut out both wall surfaces carefully, you won't have to make repairs to either the inside or the outside walls because both the heater and the exhaust flange have edges on them that will cover the cut-out areas.

Follow the instructions to ignite the unit, set the integral thermostat to the desired temperature and start saving money. If you have an electric-resistance heating unit, store it for use in an emergency.