Buying Guide - Understanding Energy Efficient Ratings Buying Guide - Understanding Energy Efficient Ratings

Energy Star LogoThis easy-to-read guide may help you understand how appliances are rated for efficiency, what the ratings mean, and what to look for while shopping for new appliances.

The ENERGY STAR label is the government's seal of approval. It was created by the U.S. Department of Energy and the U.S. Environmental Protection Agency. These agencies set the criteria to help shoppers for large and small home appliances identify the most energy-efficient products on the market. ENERGY STAR-labeled appliances exceed existing federal efficiency standards, typically, by 13 to 20 percent, and as much as 110 percent for some appliances. Customers can be assured that the appliance being purchased is a high-performance product which will reduce the operating cost of that appliance or product every month during the course of its lifetime.

Appliances Rating Special Considerations
Natural Gas
and Oil
AFUE is the Annual Fuel Utilization Efficiency rating. The AFUE measures the seasonal or annual efficiency. For ENERGY STAR® products, 90 is the AFUE rating. Size is one of the most important factors affecting the efficiency of the AFUE. Too large a system costs more and operates inefficiently. Bigger is not always better! Have a professional assess your needs and recommend the type and size of system you should purchase.
Room Air
EERis the Energy Efficiency Rating. The higher the EER, the more efficient the unit is.

ENERGY STAR® units are among the most energy-efficient products and exceed minimum federal standards by at least 15%.

Two major decisions should guide your purchase. Buy a correctly sized unit*! Buy an energy-efficient unit!

If the room is very sunny, increase capacity by 10%. If the unit is for a kitchen, increase the capacity by 4,000 Btu per hour.

Central Air
SEER is the Seasonal Energy Efficiency Rating. SEER rates the efficiency during the cooling season. Look for a SEER rating of 12 or above. Air conditioners that bear the ENERGY STAR® label are at least 20% more efficient than new air conditioners that meet the federal minimum standards for efficiency and may be twice as efficient as some existing systems. Contact a professional for advice on sizing a central air system.
Heat Pumps
SEER indicates cooling efficiency. HSPF is the Heating Seasonal Performance Factor and indicates heating efficiency. If you live in a cool climate, look for a heat pump with a high HSPF. If you purchase an ENERGY STAR® heat pump, you are getting a product that is in the top 25% for efficiency. Contact a professional for advice on purchasing air-to-air heat pumps.
Refrigerators and
Look for the FTC (Federal Trade Commission) label on the appliance to tell you how much electricity, in kilowatt-hours (kWh) a particular model will use in one year. The smaller the number, the less energy it uses. Look for an "energy saver" switch on models with the freezer on top. When buying a frost-free refrigerator, find one with an energy-efficient option. Refrigerators with freezers on top are more efficient than those with freezers on the side. Look for heavy door hinges, which create a good door seal. ENERGY STAR®-labeled units exceed federal standards by at least 20%.
Dishwashers EF is the Energy Factor. This number represents the number of complete cycles that a dishwasher will operate while using one kilowatt-hour of electricity. ENERGY STAR® dishwashers have an EF of 0.52 or greater, 13% better than current federal standards. Look for features that will reduce water use, such as booster heaters and smart controls. Ask how many gallons of water the dishwasher uses during different cycles. Dishwashers that use the least amount of water will cost the least to operate.
Look for a thermostat that allows you to easily use two separate programs; an "advanced recovery" feature that can be programmed to reach the desired temperature at a specific time; a hold feature that temporarily overrides the setting without deleting preset programs. Look for the ENERGY STAR® label.
EF stands for Energy Factor. The EF is the number of complete cycles that a clothes washer will operate while using one kilowatt-hour of electricity. ENERGY STAR® units must have an EF of 2.5 or more above the current federal standard of 1.18. Look for the following design features that help clothes washers cut water usage: front-loading design, water level controls, "suds-saver" features, spin cycle adjustment, and large capacity. For double the efficiency, buy an ENERGY STAR® unit.
Hot Water
EF is the Energy Factor rating the overall efficiency of the heater. The FHR is the First Hour Rating of the system, which measures the maximum hot water the heater will deliver in the first hour of use from a cold start. Buy a water heater with a thick insulating shell. If you want hot water fast, the FHR rating will be important to you. Sizing is important � call your local utility for advice.

*What size air conditioner to buy?

Area in
square feet
100 to 150 5,000
150 to 250 6,000
250 to 350 7,000
350 to 400 9,000
400 to 450 10,000
450 to 550 12,000
550 to 700 14,000
700 to 1,000 18,000

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