AFUE Annual Fuel Utilization Efficiency, an efficiency rating as set forth by the Department of Energy to rate natural gas, propane and oil heating equipment. The rating is based on average usage, including on and off cycling. Use this rating when comparing systems just as you would mileage ratings on cars. The higher the AFUE rating, the more efficient the appliance and the lower the operating costs. |
Batt Insulation Pre-cut insulation, usually fiberglass or rock wool. Best suited for standard joists or rafters spaced 16 or 24 inches apart. |
Blanket Insulation Rolls of fiberglass or rock wool. |
BTU British Thermal Unit, the amount of heat needed to raise 1lb. of water 1 degree F. A BTU is about equal to the heat produced by one lighted match. |
Kilowatt One thousand watts of electricity. |
Kilowatt Hour A unit of measurement by which BGE and other electric utilities bill their customers. One kilowatt hour is 1,000 watts consumed for 1 hour. |
Loose Fill Insulation Fiberglass, rock wool or cellulose which can be poured or blown in. Good method for insulating enclosed spaces, nooks and corners. |
Rigid Board Extruded polystyrene, bead board, urethane board which provides high insulating value with relatively small thickness. |
R-Value R stands for materials resistance to heat flow; the higher the R Value the better the material insulates. |
SEER Seasonal Energy Efficiency Ratio, the total cooling of a central air conditioner or heat pump in BTUs in its normal annual usage period divided by the total electric energy input in watt-hours during the same period. The higher the SEER rating, the more efficient the unit and the lower its operating costs. |
Therm One-hundred thousand BTUs of heat. |
Therm Factor A measurement of the actual heat content of the gas flowing through your meter. The prices at which BGE both buys and sells gas are determined by the heat content of that gas, and that content varies from month to month. The gas meter measures the volume of gas, and the therm factor converts that volume to heat content. |
