REDUCING ENERGY CONSUMPTION
Steps Any Homeowner Can Take to Save Energy

Contents There are a number of things that all homeowners can do to make significant reductions in their energy consumption, whether or not they are embarking on a major home construction or remodeling project. These include the following steps that the owners of this house have taken to reduce their energy consumption and that in turn contribute to the overall energy efficiency of the house.

1. Monitor Energy Consumption.

Just as keeping a record of the foods eaten each day can help people eat less and lose weight, so can keeping track of the amount of energy used help homeowners reduce their energy consumption and their energy bills.

The owners of this house had always considered themselves to be pretty savvy about using energy efficiently but discovered that they could do a lot better when they began monitoring their actual energy consumption in their former home. They experimented with compact fluorescent lights (CFLs) in a few fixtures and saw the impact immediately in lower electric bills. They gradually replaced most of the incandescent bulbs in the house with CFLs, ultimately reducing their electrical consumption by 30 percent.

Electrical consumption in the new house is roughly 70 percent lower than it was in the former home. Big contributors to this high performance include wide use of CFLs, of course, as well as the selection of a super-efficient clothes washer and a super-efficient dish washer, and reliance on ceiling fans in the main living areas rather than air conditioning on all but the hottest days.

Daily monitoring of energy usage continues and has led to further adjustments. Consumption is lower in year two, for example, because the owners turned off the small basement refrigerator during the winter months and discontinued the use of the air handling system.

2. Replace incandescent bulbs with compact fluorescent lights.

Most of the energy consumed by a standard incandescent bulb is wasted; 90 percent is given off as heat while only 10 percent is converted into light. A compact fluorescent light (CFL) is much more efficient, using roughly one-fourth of the electricity an incandescent bulb consumes to give off the same amount of light. CFLs cost more initially, but they last ten times longer and easily pay back their higher purchase price through lower utility bills. Simply replacing the incandescent bulbs in the five most heavily used fixtures in a home, as recommended by ENERGY STAR, will result in at least $60 in energy savings every year.

Halogen lights use slightly less energy than standard incandescent bulbs, but they put out a great deal of heat. This can be dangerous (especially in the case of halogen torchieres) and can also add to the cooling load of a home during hot weather. By comparison, CFLs are nearly three times as efficient and produce far less heat.

CFLs are now available in hundreds of different styles and a range of colors, including "warm" colors comparable to incandescent lamps. The color that a light bulb will emit is indicated by its Correlated Color Temperature (CCT), which is measured in degrees Kelvin. Incandescent lamps have a CCT of 2700 as do the residential CFL models typically found in retail stores. CFLs with higher numbers (and correspondingly "cooler" colors) are also available, from a warm white (3000 degrees K) to a cool white (4100 degrees K), and even higher. Lamps in a shared space will look best if they are all of the same color temperature.

While still living in their former home, the owners replaced most of their incandescent bulbs with CFLs and found that they reduced their electrical consumption by 30 percent. CFLs are used almost exclusively in the new house. Exterior landscape lighting is solar-powered.

3. Choose ENERGY STAR appliances

ENERGY STAR-labeled appliances meet strict guidelines for energy efficiency set by the U.S. Environmental Protection Agency and the U.S. Department of Energy. The label helps consumers easily identify products that use less energy, reduce home utility bills, and help protect the environment. The savings can be significant: a home that is fully equipped with ENERGY STAR-qualified products will operate on about 30 percent less energy than a house with standard products and will save the homeowner about $450 per year.

A companion program--the Super-Efficient Home Appliances Initiative of the Consortium for Energy Efficiency (CEE)--promotes a subset of "super-efficient" ENERGY STAR appliances. As part of this initiative, CEE has developed performance specifications for super-efficient clothes washers, dishwashers, refrigerators and room air conditioners and endorses appliances that are generally in the top 25 percent of efficiency.

A third resource for consumers is the yellow-and-black EnergyGuide label that manufacturers of most major home appliances are required to attach to their products. Appliances covered by the Federal Trade Commission's Appliance Labeling Rule include refrigerators, freezers, dishwashers, clothes washers, room air conditioners, water heaters, furnaces, boilers, central air conditioners, heat pumps and pool heaters. The label provides an estimate of that appliance's annual energy use, together with estimates for similar models, as well as an estimate of the annual operating cost for the appliance.

  • Clothes washers are among the most energy-intensive appliances in the home and offer the greatest potential for energy savings. An ENERGY STAR publication estimates annual savings of $41 (in 2000 dollars) in home electrical bills with an ENERGY STAR-qualified clothes washer compared to a standard new machine. (Savings of $8 per year are estimated for an ENERGY STAR dishwasher and savings of $4 per year for an ENERGY STAR refrigerator.)

    Even among ENERGY STAR-qualified clothes washers there is a wide range of efficiency, with some models as much as two to four times more efficient than others.

    • The more efficient the machine, the higher its Modified Energy Factor (MEF), which takes into account the capacity of the tub, the energy used for a load of laundry, and the dryer energy required to remove the remaining moisture in the wash load.

    • Since heating water accounts for 80 to 85 percent of the energy used in washing clothes, selecting a machine that uses less water is also important. The lower a machine's Water Factor (WF)--the number of gallons of water needed for each cubic foot of laundry--the more efficient its use of water. Using cooler water for washing and rinsing can also make a big difference; switching temperature settings from hot to warm water can cut energy use in half.

    According to the American Council for an Energy-Efficient Economy, front-loading washing machines continue to earn the highest energy-efficiency ratings. These horizontal-axis machines tumble the clothes in a partially-filled tub of water; by contrast, vertical-axis top-loading machines fill up completely with water and agitate the clothes to clean them. Newer top-loading models that spray rinse water on the clothes (rather than soaking them in a full tub) are more efficient than traditional models, but they don't rank among the ACEEE's 20 top-rated machines.

    Front-loading washers use 50 to 70 percent less energy than traditional top-loading washers and 30 to 60 percent less water. They generally are more expensive than vertical-axis washing machines, but their substantial energy and water savings will more than offset their higher purchase price.

  • Although clothes dryers are typically the second or third largest energy-consuming appliances used in the home, they are not rated by ENERGY STAR because the different models don't vary much in the amount of energy they use. Nor are clothes dryers required to display an EnergyGuide label. The more energy-efficient dryers are those with a control that shuts off the machine when the clothes are dry. These controls range from simple timers, which rely on the user to guess how long the load will take to dry, to temperature sensors, which indirectly estimate dryness by sensing the temperature of the exhaust air, to moisture sensors--the most effective--which directly measure dryness.

    In most parts of the country, gas dryers will cost less to run than electric dryers. The cost of drying a typical load of laundry in an electric dryer is 30 to 40 cents compared to 15 to 25 cents in a gas dryer.

  • For dishwashers as for clothes washers, most of the energy used is the energy required to heat the water consumed. An efficient dishwasher, therefore, is one that uses less water to do the job. The most water-efficient dishwashers on the market today use about five gallons of hot water per load in light or energy-saving cycles, compared to eleven gallons or more for conventional dishwashers in the same mode.

    In addition, virtually all dishwashers available today have a built-in booster heater, which further heats the water to the higher temperature required for dishwashing, so the homeowner can reduce the setting for the home's hot water heater to 120°, the highest temperature needed for other household uses. Another energy-saving option is a switch that allows the user to choose between heated- and unheated-air drying.

  • Of all appliances, refrigerators are the single biggest consumer of electrical power in most households, accounting for about 15 percent of all residential electrical usage. Advances in technology, however, have improved refrigerator efficiency substantially over the last 20 years, making it cost-effective in many cases to replace a still-working refrigerator with a current model. ENERGY STAR-qualified refrigerators use at least 15% less energy than required by current federal standards and 40% less energy than conventional models sold as recently as 2001.
4. Use less water

Fresh, clean water is scarce and getting more so. Moreover, conserving water is an important means of saving energy. Reducing the demand for water can help to save rivers and wetlands, maintain aquatic habitats, and protect groundwater from depletion and contamination. Using water more efficiently also helps reduce the amount of energy needed to pump, treat and heat water and to treat wastewater.

In addition to making water efficiency a criterion when selecting appliances (as described above), installing water-efficient plumbing fixtures can go a long way towards protecting this valuable natural resource.

  • Toilets are the greatest water user in the house, accounting for over one-quarter of the total daily indoor water use in a typical single-family home. Installing high-efficiency toilets, however, can result in dramatic water savings. "Low flush" residential toilets--toilets using 1.6 gallons of water per flush (compared to the 3.2-gpf standard of older models)--have been shown to save an average of 10.5 gallons of water per person daily.

    The Caroma dual flush toilets used in this house reduce water use still further. The key feature of these toilets is Caroma's 0.8/1.6 gallon two-button technology--one button for liquid waste and the other for solid waste.

  • Water-efficient showerheads and faucets are also important water-saving devices. Low-flow showerheads cut the water flow through the showerhead to levels below the federal minimum standards for showerhead flow rate. By replacing standard 4.5-gallon-per-minute showerheads with 2.5-gallon-per-minute heads, a family of four can save approximately 20,000 gallons of water per year.

    Flow reducers, which fit into the aerator at the tip of the faucet, can be installed easily in most conventional faucets. Newer, more efficient kitchen and bathroom faucets are also available. These use only 2 gallons of water per minute compared to standard faucets, which use 3 to 5 gallons per minute.

5. Use window treatments to control heat loss and heat gain.

The owners have installed Hunter Douglas duette shades on all the windows of this house and use them conscientiously--at night in the winter months to retain heat and on sunny days in the summer to block unwanted heat gain.

Links and Resources

  • The Rocky Mountain Institute has put together a series of nine practical guides describing what the average homeowner can do to save energy. Topics include lighting (No. 2), cleaning appliances (No. 6), and kitchen appliances (No. 8).

  • Consumers looking for help in identifying energy efficient appliances will find information on more than 50 categories of products on the ENERGY STAR website. Also outlined are five easy steps that consumers can take to make their homes more energy efficient.

  • The U.S. Department of Energy's Energy Savers Tips on Saving Energy & Money at Home offers an array of practical solutions for saving energy throughout the home.

  • The American Council for an Energy-Efficient Economy's Consumer Guide to Home Energy Savings is a comprehensive reference to energy-efficient home appliances and techniques for saving energy around the home. A condensed online version, including a Home Energy Checklist for Action, is also available.

Website prepared by Eleanor Revelle and Ellen Galland.
Last updated: April 2007