Heat Your Home with Less Energy
Many people dread winters, and not just because of the cold:
depending on where you live, your furnace or boiler may account for more than 60
percent of your yearly energy costs. If it’s at least 20 years old, consider upgrading
to a higher-efficiency model, which will significantly reduce heating costs and
avoid as much as 2.5 tons of heat-trapping carbon dioxide emissions each year.
Furnaces and boilers are rated by their annual fuel utilization efficiency (AFUE), which represents the percentage of fuel converted to heat. Older models have average AFUE ratings of 65 to 72 percent, whereas today’s Energy Star-rated models have a minimum AFUE rating of 85 percent for oil furnaces and oil/gas boilers, or 90 percent for gas furnaces.* Upgrading from an AFUE of 70 percent to 85 percent would save you approximately $17 for every $100 spent on fuel; upgrading to 95 percent would save you $26. This savings (up to $250 or more per year if you spend $1,000 for home heating) could quickly cover the higher cost of a super-efficient unit.
Before you shop for a new furnace or boiler, weatherize your home. Installing weather stripping around doors and windows, then sealing and insulating ceilings, walls, and air ducts, reduces heat loss, allowing you to purchase a smaller heating system. (In general, properly sized heating systems operate most efficiently.)
In addition to a high AFUE rating, consider these energy-saving options:
Condensing furnaces and boilers capture heat from combustion gases that would otherwise be lost through the flue, making these units about 10 percent more efficient than conventional models.
Heat recovery ventilators (HRVs) can improve a forced-air system’s efficiency by capturing up to 85 percent of the heat from the outgoing air and using it to warm the incoming air, reducing the furnace’s heating load.
Regardless of whether you upgrade your heating system, make sure it runs at its optimum efficiency by:
- Having the system serviced annually and cleaning the air filter monthly, which can reduce heating costs 5 percent.
- Setting your thermostat to 68 degrees or lower when you’re at home during the day and 55 degrees when you will be sleeping or away. Every two-degree reduction in temperature saves up to 10 percent on yearly heating costs and reduces carbon emissions by 6 percent.
* All-electric furnaces can have AFUE ratings of up to 100 percent because there is no fuel combustion in the unit, thus no heat lost through exhaust gases.
