Home Energy Diet

THIS CHAPTER LISTS THE MOST COMMON household electrical appliances, along with some comments about their energy usage, and ideas on how to reduce their contribution to your energy bills.

The “Appliance Use Chart” in Appendix C goes on to list over 100 household appliances along with their average power usage. It will help you to:

Air Cleaner: A small, plug-in, household-size air cleaner uses approximately 40 watts on low, 60 on medium, and 120 on high speed. A high quality vacuum cleaner with a good filtering system may reduce or eliminate the need for an air cleaner. Smokers should have a place outside to keep second-hand smoke out of the house.

Air Conditioning: Keep the filter clean. Reducing humidity can offer increased comfort at higher temperatures. Using an air conditioner in conjunction with a ceiling fan will offer increased comfort levels at higher temperatures.

Answering Machine: A phantom load, always consuming power, from five to ten watts. Look at the “wall cube” adapter that plugs into the power outlet to find the wattage.

Aquarium, Filter Pump: Various sizes, 5 to 25 watts. Ten watts is common for a 20-gallon aquarium.

Aquarium, Heater: Various sizes from 50 to 300 watts. 75 watts is common for a 20-gallon aquarium. Keep the aquarium in a warm room.

Aquarium, Light: Various sizes — usually a 15-watt fluorescent bulb. These lights can be used for long periods, so if the light is not fluorescent, switch it over!

Battery Charger: Varies. The cheaper hardware-store variety is very inefficient (about 60 percent). A 6-amp charger might draw 125 watts from the wall socket, but only deliver 75 watts to the battery. Look for more efficient, two-stage electronic chargers.

Blanket, Electric: Various sizes. Check the tag. These will cycle on and off depending on the thermostat setting. Don’t forget to turn it off in the morning!

Blender: Average draw is about 400 watts, with a small variation based on the speed and how hard it is working.

Boom Box: Varies from 5 to 50 watts. A good choice for the off-grid house, they use far less power than a full-blown stereo for times when you don’t need to rock the house.

Bug Zapper: These things are best at attracting more bugs and annoying the neighbors. Unplug it. Uses about 40 watts.

Clothes Dryer, Electric: A potentially high use item, the main power draw in an electric dryer is the 5,000-watt heating element. The thermostat will cycle the element on and off so that the clothes do not burn. This cycle factor may allow the heating element to be “on” about 75 percent of the time. If your clothes take an hour to dry, the heating element will consume about 3.75 kWh per load, and an additional 0.3 kWh per load for the drum motor. Some new dryers have moisture sensors that turn the unit off automatically when the clothes are dry. Depending on local fuel prices, it may be worth while to switch to a gas dryer. Use a front-loading, ENERGY STAR-labeled clothes washer that will remove more water from the clothes in the final spin, reducing dryer run-time.

Clothes Dryer, Gas: The only electrical consumption here is the motor, using about one quarter to one half kWh per load, depending on the length of the cycle. It is important that the gas dryer be properly vented so that combustion by-products don’t enter the home. New gas dryers have electronic ignition so there is no wasteful pilot light.

Clothes Dryer Venting: Would you pour two or three gallons of water on your basement floor? Dryers need to be vented to the outdoors. Dryer ducting (especially the flexible type) can easily clog with lint and water, effectively stopping air movement and ensuring wet clothes and high electric bills. Keep ducting short with minimal turns that aren’t too tight, avoid dips or valleys, and try to use smooth-wall rigid ducting. Flexible ductwork may be easy to install, but its corrugations slow the air movement down and restrict flow, and it’s easy to crush. Clean the vent pipe once a year or as needed. Use a tight-sealing vent hood so that cold air doesn’t enter the house through the dryer, and periodically look at the vent from the outside to be sure that air is blowing out of it.

If you don’t connect the vent and allow all that moisture to stay in the house, you may develop indoor air quality problems along with structural damage caused by the moisture. If you want to capture some of the moisture from the dryer because your house is too dry, you need to find out why your house is so dry by reading Chapter 6. The worst case is that you have a dryer vented to the basement, and then operate a dehumidifier to deal with the excess moisture.

• Dry full loads, but don’t overload the dryer as it will take more energy to dry the clothes.

• Don’t over-dry. Some new dryers have moisture sensors that automatically turn the dryer off when clothes are dry.

• Wash and dry similar types of clothing together. Different fabrics dry at different rates.

• Be sure the dryer is vented to the outside to avoid moisture and lint build-up in the house.

• Be sure the outlet vent ducting is free of tight turns, or elbows. Lint can build up at elbows, slowing airflow out of the machine, increasing drying time, and creating a potential fire hazard.

• Rigid venting is better than corrugated flex vent at keeping air moving and avoiding blockages.

• Don’t exceed 25 feet of vent length (or per manufacturer’s instructions).

• If you like how your towels feel after coming out of the dryer, try using it for only ten minutes or so and then hang dry.

• If your clothes tend to take longer to dry than they used to, perhaps the thermostat or heating element has gone bad. Are the clothes hot but not dry? Check the venting system.

Fig. 3.2: The inside of the dryer vent in Figure 3.1, showing heavy lint buildup.

The US Consumer Product Safety Commission estimates that in 1998, clothes dryers were associated with 15,600 fires, which resulted in 20 deaths and 370 injuries. Fires can occur when lint builds up in the dryer or in the exhaust duct. Lint can block the flow of air, cause excessive heat build-up, and result in a fire in some dryers.

Plastic or foil duct material can burn, and lint is highly combustible. Only rigid metal venting should be used. Metal venting also resists crushing better than plastic and foil, Reduced airflow and the resulting lint build-up reduce dryer efficiency and create conditions ripe for a fire. Reduced airflow can also cause overheating and wear out the clothes and the dryer faster. Many state and local municipalities have placed requirements on new and remodeling projects to include all-metal dryer venting.

Figure 3.1 shows a dryer vent that started to burn and Figure 3.2 shows the inside of that vent.

Clothes Washer: Top-loading washers use from 30 to 60 gallons of water and 300 to 500 watt-hours per load (not including water heating). Up to 90 percent of the energy needed to wash clothes is attributed to heating water, so using cold water is the biggest energy saving action you can take when washing clothes. There are many good cold water detergents on the market. Experiment!

My horizontal axis (front-loading) washer uses about 200 watt-hours per load for the longest possible load. The water well pump requires an additional 33 watt-hours to pump the 25 gallons (with extra rinse) needed by the machine. If you have municipal water, you’ll save on water and sewer costs. The front loader’s action is gentler, reducing wear and tear on clothes, and it spins much more water out of the clothes, allowing for shorter drying time.

Clothes washers are rated for efficiency using the Modified Energy Factor (MEF), a figure that considers washer capacity, electrical energy used, water heating energy required, and how dry the clothes are when they come out of the washer. The higher the MEF, the more efficient the washer is. When buying new, look for a Modified Energy Factor of 1.42 or higher.

Coffee Maker: A popular automatic coffee machine consumes about 100 watt-hours to brew six cups. When on, a coffee maker can draw 800–1,100 watts and cycle on and off to keep the coffee warm. This is a potentially big electric user, so turn it off when you’re done.

Computers: Computer energy consumption varies from 10 to 40 watts for a laptop, and 90 to 150 watts for a desktop model. If your computer salesperson tells you it’s better to keep the computer on all the time, ask if it would be better

• Wash full loads only (but don’t overload) to save water, time, and energy.

• Weigh a load of clothes once to get an idea of what 15 pounds (or whatever the rated weight for your machine) looks and feels like. When buying, size your washer and dryer for equivalent load sizes.

Off-Grid Tip

I use an ENERGY STAR-labeled laptop computer in my solar-powered home office that uses only about 20 watts and goes to sleep (using less than five watts) after ten minutes. A laptop is the most efficient choice, though generally more expensive to buy than desktop computers. The additional power consumption of a desktop model can strain your solar-power budget. In order to power the desktop computer from my solar electric system, I would need to buy an additional 170 watts (about $1,000 worth) of solar electric panels. Table 3.1 shows the savings of using a laptop six hours a day instead of a desktop model.

for him or her to pay your electric bill. There really is no good reason to keep the computer on when it’s not in use. Today’s modern electronics are not as prone to on-off cycling wear and tear. If you keep your computer on to answer your faxes, you would do well to invest in a lower-power fax machine. If you’re away from the computer for more than an hour, turn it off. Screen savers do not reduce electricity use. Sleep settings help, varying the power draw from not much less than the rated power to a quarter of that, depending on the model. Printers, copiers, scanners, and other computer peripherals are all phantom loads. Plug the computer and peripherals into a switched power strip so that you can turn everything off easily and avoid any phantom power consumption.

Crock Pot: Draws around 300 watts over a long period of time. These are in the expensive category of electric resistance heaters, but can still use less power than an electric oven (see Cooking Diet).

Dehumidifier: Before using a dehumidifier, be sure you need one. It should be a last resort in dealing with moisture problems. Try to eliminate the source of the moisture problem. Have you installed gutters and sloped the ground away from your house to drain water away from the foundation? Does the problem occur throughout the house or just in certain areas? Showers, plumbing leaks, unvented dryers, and dirt floors can contribute to high humidity in your home. Human activity creates moisture that should be removed at the source (showers and cooking). Perhaps an exhaust fan is all that’s needed to remove moist air from a damp room. This can be accomplished in smaller homes by running the bathroom exhaust fan. For larger homes, an air-to-air heat exchanger would be an efficient way to improve indoor air quality and deal with moisture problems. You can read more about these issues in Chapter 6.

If you do need a dehumidifier, buy the correct size. Dehumidifiers are sized by the amount of water the appliance removes from the air in pints per 24

• Avoid using the temperature boost setting — water heating can account for up to 80 percent of the energy required by a dishwasher.

• Keep your water heater temperature as low as possible and let the dishwasher heat what it needs.

• Try different settings and detergents to see which gives you the best performance (my dishes come out cleaner by filling the soap dispenser only two thirds rather than completely full).

• Air dry dishes — use the “no-heat dry” setting or allow dishes to air dry by opening the door after the wash cycle is complete.

• Don’t rinse dishes before loading into the dishwasher — just scrape them off.

hours. Efficiency ratings are described as how much water can be removed for each kWh of power used. These ratings range from 2.7 pints per kWh (less efficient) to 5.7 pints per kWh (more efficient). To help you decide how much drying power you need, see the dehumidifier sizing chart, Table 3. 2.

A dehumidifier’s operation is similar to that of an air conditioner, and they can use nearly as much power. If you must use one, try not to overuse it. Comfortable relative humidity in a home is around 35–55 percent, and up to 70 percent is tolerable for long-term paper storage. Invest in a hygrometer to keep track of relative humidity so that you can adjust the dehumidifier’s controls accordingly. Dehumidifiers use condensing coils to remove moisture. If the space is too cold (below 60°F), reaching the too cold (below 60°F), reaching the condensation point is more difficult and may cause icing of the coils, greatly reducing the dehumidifier’s efficiency.

Dishwasher: Older dishwashers use 12 or more gallons of water, while those built after 1994 use between seven and ten gallons. My Asko dishwasher uses under five gallons of water per wash. Most of the energy used by a dishwasher is due to heating water, but the power consumption will vary with the control settings. Some have the option to raise the water temperature higher. Without using the temperature boost or heat dry cycle, the Asko uses 0.5kWh per normal cycle. With the temperature boost on, it will use 1.3 kWh per load, and the heat-dry cycle uses an additional 0.4 kWh. In this case, keeping the temperature boost and heat-dry cycles off saves 312 kWh per year if I do five loads a week.

Table 3.3 is a savings table that shows the potential savings of turning off the heat-dry setting on the dishwasher.

Dishes: By Hand or by Machine?

Does it use more water and energy to wash dishes by hand or in a machine? Finally, there is a definitive answer. A study conducted by the University of Bonn, Germany, reported that volunteers washing dirty dishes in a sink used an average of 27 gallons of water and 2.5 kWh of water-heating energy to wash a complete 12-place dinner setting. An automatic dishwasher handling the same number of equally dirty dishes used only 4 gallons of water and about 1.5 kWh of total electrical energy. After the volunteers were finished with their task, about half the dishes were judged to be “really dirty” or at least not acceptable to be placed on a dinner table, while the machine dishwashers offered consistently cleaner dishes.

Fan, Bath: Look for an energy-efficient model using less than 40 watts with a “sone,” or sound intensity, rating of less than 1.5 sones. Be sure it is vented to the outdoors, not into the attic where it can cause moisture, mold, or rot problems by introducing moist air from the house. Using rigid ducting will increase the airflow through the fan. Flexible ductwork may be easy to install, but its corrugations slow the air movement and restrict flow, while sagging vents can trap mold-growing moisture. Make sure the vent joints are properly sealed with foil tape, and keep elbows to a minimum.

Run the fan during and at least 15 minutes after showers to remove moisture from the room.

Fan, Attic: One way to cool your house in the summer is to use a fan that exhausts hot air from the attic and pulls cooler, outside air into the attic. This setup only works if there is enough air available from outside the attic — meaning outside the house — to make up for the air being removed by the fan. What you want to avoid is pulling conditioned air from the living space below into the attic, wasting energy and possibly bringing potentially damaging moisture into the attic. The attic should be well insulated and completely air-sealed from the living space below.

Using a whole-house exhaust fan for ventilation during warmer weather can be accomplished by using a fan installed in the top-floor ceiling that pulls air from the living area and exhausts it into the attic. In this case, it is important to ensure that there is enough free-vent area between the attic and the outdoors to match the air flowing through the fan. It is equally important to be sure that any air leaks between the attic and the house are thoroughly sealed, and that the exhaust fan is covered with insulation and seals tightly when not in use. This will prevent heat loss from the house during winter, and potentially damaging moisture problems in the attic. Tamarack Technologies makes one such whole-house fan.

You may want to consider adding insulation to the attic, which will keep excess heat out of the living area and reduce your heating and cooling loads. Solar-powered, temperature-controlled attic fans are available that will operate automatically when the sun is out and the attic is hot.

Fan, Ceiling: Use a reversible fan and switch it so it blows downward in the winter, bringing the heat down to where people are. In the summer, reverse the direction to keep the air moving. Turn off the fan when you’re not in the room — they only work when someone is there to enjoy the breeze!

Fan, Window: On average, a three-speed box style window fan will use 60 watts on low speed, 100 watts on medium, and 200 watts on high. Many people run fans at night for “white noise” to block out extraneous sounds and help them sleep better. It’s probably just as easy to get into the habit of sleeping without the fan as it was to get used to sleeping with it. Try earplugs, or if you really need white noise, try tuning a small radio to the static in between stations and put it across the room. It will save you a noticeable amount of power and money.

Fan, Range Hood: These are recommended to remove moisture, heat, and odors from the kitchen. Beware the high-powered exhaust fan as it may back-draft the chimney used for the heating system or water heater, pulling exhaust fumes into the house. If it’s a big enough fan, you may need “make-up” air from a dedicated duct or nearby open window.

Fax Machine: A phantom load. If you’re not expecting faxes, put it on a power strip and turn it off when not in use.

Garage Door Opener: The typical 0.5HP motor used ten minutes a day consumes about 100 kWh per year. There is an additional phantom load of around four watts for the remote-control receiver electronics, adding up to 35 kWh per year.

Hair Dryer: A big user in the resistance heat category. Maybe it’s time to try the natural look. My wife’s hairdresser gets a big kick out of the fact that she doesn’t use a hair dryer. We both are amazed that she is the hairdresser’s only client who doesn’t regularly use a blow dryer!

Heat Lamp: You may not like this, but if you need heat, get it from your heating system. Heat lamps are high wattage incandescent bulbs ranging from 200 to 500 watts.

Heat Tape: A last resort to keep pipes from freezing. Look for the root cause of the problem, such as a cold air draft blowing on the pipe. Look closely around the pipe for clues. Use caulk or expanding foam to seal holes that may exist in the basement wall or perimeter band. Insulate the perimeter band joist cavities, as well as the pipes.

Heater, Engine Block: These are not all that necessary anymore due to low temperature fuel mixes and low viscosity engine oil. My diesel car and diesel generator have no trouble starting down to 25° below. I am diligent about using the proper grade of oil for cold weather, which helps greatly for low temperature starting. If you really need a block heater, put it on a timer to turn on 30 to 60 minutes before you need the vehicle.

Baseboard heat demands 250 watts of power per foot. An average size home might need 50 to 100 feet, depending on the climate and size of the home.

Heater, Portable: Those little cube-style electric heaters average about 1500 watts. After an hour, it has used 1.5 kWh. Those portable electric, oil-filled radiator-style heaters are no exception; 1500 watts is 1500 watts, despite what the advertising says. The advantage these heaters have is “thermal mass,” meaning the material inside can “store” heat, much like a rock outside stays hot for a few hours after the sun sets, then radiates the heat to you. These heaters may save a bit because the radiant heat helps you feel warmer at a lower thermostat setting.

Heating System, Hot Water Boiler: Varies depending on size and your climate. A boiler circulator pump uses about 100 watts. A well-insulated and air-tight house, with a properly sized energy-efficient heating system, coupled with a programmable thermostat will help keep your heating costs low.

Heating System, Furnace: Varies depending on size and your climate. A furnace-blower motor can use 250 to 1,000 watts, depending on the size. A rule of thumb for furnace-fan power consumption is that you can expect to use approximately one kWh for every therm (Ccf) of natural gas, gallon of oil, or gallon of propane. Again, a well-insulated and air-sealed house with a properly sized, energy-efficient heating system, coupled with a programmable thermostat will help keep your heating costs low.

Hot Tub: A well-insulated outdoor hot tub can use from 3 to 12 (or more) kWh per day depending on the climate, size, and temperature. If insulation is missing from the bottom or sides, you can try spraying on a two-part urethane insulation. These “Froth-Packs” can be found at good hardware stores or from efficiency product suppliers such as The Energy Federation <www.efi.org>.

Most hot tubs are electrically heated, but they can be retrofitted to operate less expensively off a boiler heating system. Contact a good plumber or heating contractor.

Humidifier: Why is the air inside your house too dry? Human activity produces moisture. If your house is too dry, it may be due to excessive air moving through the house, carrying all that moisture outside. Try to eliminate the need for humidification by decreasing air migration into and out of the house. If you need to run a humidifier in the winter, be sure to keep an eye on humidity levels with a hygrometer so that the relative humidity does not rise over 40 percent. See also Chapter 6.

Lighting: OK, maybe you tried those efficient bulbs in the past and you gave them away. Let me reassure you that efficient lighting products have come a long way in the past ten years and I would encourage you to try them again. Lights are one of the easiest things in your home to make energy efficient by switching to low wattage compact fluorescent lamps (CFLs). There are many sizes and styles of CFLs on the market today using one-quarter to one-third the power with equivalent light output, and lasting six to ten times longer than an incandescent light. Those that have electronic (not magnetic) ballasts generally offer a better light quality, and flicker-free start-up and operation. Ask your electric company if they have a rebate program for CFLs. If the lights are in low-use locations such as closets, or in places where they tend to be turned on and off a lot, consider using a low-wattage incandescent bulb instead of a fluorescent bulb, as fluorescent lights may fail prematurely if used in these locations. When choosing a CFL, think about the incandescent wattage you normally use, and then divide by three. That is the fluorescent wattage you should use to replace it.

• Avoid halogen torchiere lighting. These lamps use from 250 to 600 watts and are a fire hazard. You can actually cook on top of them! Look for energy efficient torchieres using dimmable CFLs.

• Put lights where you need them. There are many kitchens with recessed lights shining wasted light onto the top of cabinets! Use low wattage, under-cabinet lights in the kitchen.

• Use overhead task lighting to concentrate light where you need it, allowing you to turn off background lights.

• Look into “Light Tubes” tubular skylights that bring light through the roof and attic, around corners and into your living area. Some brand names are Sun Tunnel, Sola-Tube and Natural Light.

• Fluorescent lighting runs cooler than incandescent, offering greater summer time comfort.

• To learn about efficient outdoor lighting and light pollution, look into the International Dark Sky Association at <www.darksky.org>.

Lighting Action

ENERGY STAR has issued a call to action:

“Make your next light an ENERGY STAR. If every US household makes their next light an ENERGY STAR, the reduction in air pollution would be equivalent to removing 1.2 million cars from the road for one year. This would amount to 8.5 billion kWh in energy savings. That’s enough to power over 808,000 homes for one year yielding $840 million in savings on power bills nationally.”

Traditional incandescent light bulbs are based on a design that’s over 120 years old! Would you buy anything else with such antiquated technology? (Well, yes, your car’s engine is about as old, and so is its starter battery, but that’s another subject). Incandescent lights are only about ten percent efficient at turning electricity into light; the rest is wasted as heat. This puts them in the electric resistance heat category.

The next wave in lighting technology is the Light Emitting Diode (LED). LEDs are those little red or green lights you see on most appliances these days. They are extremely efficient and very long lasting. LED lights are being used in some traffic signals where they not only save energy, they greatly reduce maintenance costs. The city of Syracuse installed LED traffic lights at 299 intersections, saving $225,000 in energy costs each year. The city of Chicago estimates that it could save $4.4 million a year by replacing all of its traffic lights with LEDs. White light LEDs have not yet been found to be very efficient, and this is an area of current research. Some manufacturers are putting an array of whitish-blue LEDs in a standard bulb housing that will last about 100,000 hours, and use about 4% of the power of an incandescent light, but the color rendition may not be appropriate for all locations.

Fluorescent Lights: Mercury Content, Disposal and Cleanup

A coal power plant will emit ten milligrams (mg) of mercury to produce the electricity to light an incandescent bulb over five years, but only 2.4 mg of mercury to run a compact fluorescent (CFL) bulb for the same time. A typical CFL contains about 4 mg of mercury, while a watch battery can contain between 5 and 20 mg.

Anything that contains mercury should be treated as hazardous waste. Check with your local waste collection facility for proper disposal locations. If fluorescent lights break, do not vacuum! Using rubber gloves, pick up the big pieces and put them into a plastic bag. Use wide tape to pick up smaller pieces, wash the floor, and put all cleaning materials in the plastic bag. Bring the bag to your local household hazardous waste collection facility as you do your dead mercury-containing batteries.

If you have trouble getting the kids (or your parents or your spouse) to turn off the lights, you might need to take some more serious action:

• Occupancy sensors will sense motion (or lack of it) and turn the light on or off accordingly.

• For outdoor lights, use motion and/or light sensors so the light is on only when you need it.

• Try fines — my parents would fine us kids 25 cents every time they saw one of our lights on and we weren’t using it. That was a big chunk of our allowance money back then.

Table 3.4 is a savings table that shows the potential annual savings from switching all your lights from incandescent to fluorescent.

Microwave: Uses a lot of power (up to 1,000 or more watts) while operating, but overall a very efficient way to cook, using from 11 to 50 percent of the energy of conventional ovens. Keeping the inside of the oven clean increases efficiency. See Table 3.5 for a comparison of cooking energy costs.

Motors and Pumps: In general, motors of average efficiency will use about 1,000 watts for every rated horsepower. The actual power demand depends on the motor’s size, efficiency, and how hard the pump is working. Surge current is a big issue in motors, using from two to ten times more power to turn on as compared to the amount of power they use to run continuously. So if you have a furnace that “short cycles,” or a well pump with a bad pressure tank, the motors in the equipment will cycle on and off more frequently, dramatically increasing their power consumption.

Range top, Oven, and Broiler: If you have a gas range, keep the burners clean to ensure maximum efficiency and reduce carbon monoxide production. A blue flame indicates good combustion. If you see much yellow in the flame, call for service. It is difficult to find a new gas range without electronic ignition and “glow bars” in the oven requiring electric power.

Math Box: How Much Will a Single CFL Save Over its Lifetime?

If you replace a 100-watt incandescent bulb operating four hours a day with a 25-watt CFL, it will reduce demand by:

100 – 25 = 75 watts

At four hours per day, it will reduce annual consumption by:

75 × 4 × 365 ÷ 1,000 = 109.5 kWh per year

If you pay 10 cents per kWh, the bulb will save you:

109.5 × 0.10 = $10.95 per year in electricity costs.

If the bulb costs you $10, it pays for itself in less than one year. If the CFL lasts for 10,000 hours, a burn time of four hours a day means that the bulb will last 6.8 years. An incandescent bulb’s lifetime is only about 1,000 hours, or about 250 days at four hours per day. The lifetime energy savings of this 25-watt CFL is:

$10.95 per year × 6.8 years = $74

What about the cost of the bulbs? You would need to buy ten incandescent bulbs at a total cost of about $6, in place of the single $10 CFL. Over 6.8 years, the CFL will save you a total of:

(total energy cost savings) – (the difference in bulb costs)
OR:
$74 – ($10 – $6) = $70

• Use the right size pot on the stove burner. A six-inch pot on an eight-inch burner wastes over 40% of the heat produced by the burner.

• Inspect the oven wall insulation, especially if it has been in storage for a while.

• Minimize pre-heating time. Most ovens take only ten minutes or so to heat up.

• Water will not get any hotter after it’s boiled — turn boiling water off!

• Allow sufficient air circulation inside the oven — avoid using foil on the racks, don’t overfill the oven, stagger multiple pans.

• If you keep an electric coffee maker on all day, try an insulated carafe instead • Food continues to cook after the heat is turned off and the food is removed from the oven. Turn off the oven a few minutes early and use residual heat to finish the job.

• Use the range hood exhaust fan to remove excess moisture produced by cooking.

• Avoid using foil around burners as it can block air flow and reduce efficiency.

Refrigerators and Freezers: A new refrigerator or freezer can use as little as one-half the energy of a ten-year-old model. See the refrigerator section of the “Appliance Use Chart” in Appendix C to get an idea of savings potential based on type and age.

According to the Alliance to Save Energy, refrigerators in the US alone use the equivalent of the output of more than 20 large nuclear power plants. If all the nation’s households used the most efficient refrigerators, electricity savings would eliminate the need for about ten large power plants.

I’ve heard it a hundred times: “I got a great deal on that fridge. Free!” Are you the proud owner of a free refrigerator or freezer from your brother-in-law? Well the old saying, “free ain’t cheap” applies perfectly here. If you have an old refrigerator it’s probably costing you more than it should to keep your food cold.

The Sumers’ fridge was old enough to replace anyway, but I metered it just for kicks. I estimated its use at about 2,000 kWh per year (I always add 500 kWh per year to my best estimate for those lovely colors from the 1970s: olive green, burnt orange, or chocolate brown). The metering proved a good idea — the fridge used just over 3,000 kWh per year! The likely cause of this was age, leaky door gaskets, and a self-defrost heating coil that

Cooking Efficiency

Research by the Electric Power Research Institute (EPRI) reports very high efficiency from new magnetic induction ranges using high frequency AC magnetic fields to induce heat in the bottom of iron-based cookware. Because the energy is transferred directly to the cookware, the range top’s ceramic heating element stays cool. This heat transfer method has an efficiency of 92 percent (losing only eight percent of its energy as waste heat) compared to 72 percent for a standard electric range and 47 percent for a residential gas range, and only 30 percent for a commercial gas range.

appeared to be stuck on. I suspected this because my watt meter indicated the fridge used more power than I would have expected. While your fridge or freezer is running, you can expect it to use between 200 and 400 watts. High efficiency compressors and better insulation reduce both power demand and run time.

If you happen to have an old (1950s or earlier) manual defrost fridge or freezer (the ones that look like an old Buick), you may want to think twice before replacing it. Those nice thick walls are well insulated and they were built to last. Definitely meter this old gem before replacing it.

Refrigerators, Gas: Refrigerators are available that will run on liquid petroleum (LP) gas, natural gas, or kerosene. These are typically found in off-grid homes or camps where there is no electricity or where electricity is at a premium. Most are not very big — nine cubic feet is the average size. See the analysis comparing gas to electric refrigerators in the accompanying sidebar.

Satellite Dish (including receiver): A phantom load (20 to 40 watts) and a perfect candidate for putting on a switched power strip.

Swimming Pool Filter Pump: See motors. Put it on a timer and find the optimum time needed for proper cleaning. Choose a timer rated for the size of the motor.

Buying a New Refrigerator

How do you know when it’s time to replace your refrigerator?

The answer, as usual, is that “it depends.” It depends on the difference between operating costs of the old one and a new one. A refrigerator is a major electric user in your home with a high up-front purchase cost, a long lifetime (15 years or more), and the potential to cost you far more in operating expense than purchase price. Therefore, you don’t want to buy one if you don’t need to, but if you do need a new refrigerator, you want to get a model that will not be a long-term burden on your electric bill.

The only way to be sure of how much power your fridge or freezer consumes is to meter it. A week is a good length of time to meter the fridge to get the best data, though after a day you will have a good idea of what it uses. I have metered refrigerators for only two hours with a digital meter and was able to accurately estimate their annual consumption to within ten percent. I would not recommend this short a time though, as the defrost cycle can come on at any time, throwing off your calculations.

Depending on the size and type, a new energy-efficient fridge will use from less than 1 to 1.5 kWh per day. Look for the new size and style that you need, avoid energy-guzzling options such as cold water taps and automatic ice makers. When you have a model in mind, subtract its annual kWh consumption (from the yellow Energy Guide tag) from your current refrigerator’s consumption and multiply that figure by your cost per kWh. This is your annual energy cost savings. If you don’t have access to a watt-hour meter, the Appliance Use Chart compares refrigerator and freezer usage by size and age.

Here’s an example of how much a new refrigerator can save:

Your old, olive green fridge from the 70s uses 2,000 kWh per year. The new ENERGY STAR model uses only 500 kWh per year.

2,000 – 500 = 1,500 kWh per year saved.
1500 kWh × $0.10 per kWh (use your own power cost here)
= $150 per year savings.

Your new fridge costs $700, which gives you a 4.7-year simple payback ($700 ÷ $150), or a first year, tax-free return on your investment of 21.4 percent ($150 ÷ $700). With these numbers at your disposal, you can decide if it’s worthwhile to repair or replace an old or broken refrigerator or freezer.

Television: A phantom load of up to 12 watts. If you leave it on for background noise, try the radio instead; it will use much less power. Use a switched power strip to eliminate its phantom power draw.

VCR: Another phantom load of up to 13 watts. Put it on your entertainment center’s switched power strip.

Water Cooler/Heater: These are convenient, but may use more than the convenience is worth. Put a pitcher of cold water in your fridge and use the stove or microwave to heat water as you need it.

Water Heater: A water heater is probably the second largest energy user in your home (after the heating system).

Waterbeds: Waterbeds have heaters ranging from 150 to 375 watts. An unmade king-size bed can use up to 1,800 kWh per year, a queen up to 1,200.

Be sure that your waterbed is covered and insulated so that it is not heating your bedroom.

• Avoid heating the room with your waterbed! Keep the bed covered and the room heated.

• Keep the mattress away from exterior walls to prevent heat conduction through the walls.

• Consider a quilted, insulating slip cover, a second mattress or a foam insulating pad that may allow you to turn the heater down or off.

• Check the gasket by closing the door on a piece of paper. You should feel some resistance when the paper is pulled from the door.

• Clean the condenser coils behind or under the fridge. The black coils of metal tubing you see in back of (or under) your fridge are used to transfer the heat from inside the fridge, to outside of it. Any dust accumulation around the coils will act as insulation and the fridge will work harder. Unplug the fridge every few months and vacuum the coils and around the fridge.

• Provide three inches or more of space on all sides of the fridge to allow air to move and heat to escape from the cooling unit.

• Turn off the “anti-sweat” feature. A switch inside the fridge labelled “power saver” or “winter/summer” turns on a heating element inside the fridge to prevent condensation from forming on the outside of the unit during humid summer months. If the condensation bothers you, save energy and wipe it off.

• Don’t put the fridge next to heat generators such as the stove or dishwasher.

• Take out everything you need at the same time. Do the same with putting things back.

• Keep the proper temperature. Refrigerators should be kept at 36° to 40°F and freezers at 0° to 5°. To check the temperature, try using the outdoor probe of an indoor/outdoor thermometer.

• Keep it full! Fridge or freezer, it will use less power if you keep it full. It is easier to keep jugs of water or ice cold than it is to keep air cold. This is due to the thermal mass of a material. The denser a material is, the longer it takes to absorb and release heat or cold. Opening the door of an empty fridge allows most of the cold air to escape and be replaced by warm air. The fridge then comes on to cool off the air inside. If the fridge is full and you open the door, it will take a long time for the food items inside to lose their cool. They have more thermal mass than air and hold the cold much as a rock outside stays hot long after the sun sets. A full fridge or freezer keeps food colder longer in the event of a power failure.

• Humidity makes the fridge work harder: cover foods to keep moisture in and wipe containers dry before putting them in the fridge.

• Size the fridge and freezer appropriately for your needs. Too big wastes energy and food.

• Remove the two 60-watt bulbs (which are really electric heaters) from the inside of the refrigerator, and put in a single 15-watt bulb. Although they will work, refrigerators are not a great place for compact fluorescent bulbs due to the cold.

• It’s more efficient to make ice in ice trays than to have an in-door icemaker.

• Avoid options such as automatic icemakers, cold water, and specialized compartment warmers.

Electric vs. Gas Refrigeration Costs

Is a gas refrigerator the right choice for you? It depends on what your needs are. The short answer is that they are worthwhile where electric costs are at a premium. Let’s look at the numbers.

A popular gas fridge uses about two gallons of propane gas per week. We know (from Table 1.2 in Chapter 1) that there are 91,690 Btu in a gallon of LP gas.

• In one week the fridge uses 183,380 Btus.

• In one day, it consumes 26,197 Btus.

Now let’s translate this into equivalent kWh. First, we’ll need to convert kWh to our common energy denominator, the Btu.

• We know that there are 3,413 Btus in a kWh.

26,197 Btu per day ÷ 3,413 Btu per kWh = 7.67 kWh per day.

Over the course of a year, this gas fridge uses the equivalent of 2,800 kWh. That’s five times more than a new fridge twice the size. In reality though, this is an unfair comparison because if you were to run this fridge on electricity, it might only use about 1,500 kWh per year (or 14,026 Btus per day). The reason is that the conversion of LP gas to usable cooling energy by the fridge is not a very efficient process. Much energy is lost as heat.

A gas refrigerator might be the right choice if your electric cost is more than twice your gas cost per equivalent Btu, or where you have no electricity and can easily transport gas bottles to the site.

What would it cost to operate the gas fridge over the course of a year?

2 gallons LPG per week × 52 weeks per year = 104 gallons LP gas per year.

If you pay $1.50 per gallon of LPG, that’s $156 per year. To run this fridge on electricity at $0.10 per kWh would cost $150 per year. A toss-up.

However, were you to buy an energy-efficient 19-cubic-foot electric refrigerator using 500 kWh per year, you’d pay only $50 per year in electricity cost.

If you want to go off-grid, then you need to weigh the costs of supplying propane to fuel the fridge for ten or fifteen years, and the possibility of buying extra generating and storage capacity to meet the electrical needs of the refrigerator. Often, choosing a new, highly efficient electric refrigerator and buying more solar panels is the most cost-effective solution.

Well Pump: See motors. Make sure your well pump isn’t stuck on due to a faulty pressure tank or switch, underground or in-home water leaks, faulty foot valve (check valve at the bottom of the well), or a dry well. Water-saving efforts will reduce pump run-time. Water softeners will increase pump run-time during the backwash cycle.

Power consumption of a well pump for an average family can range from 100 to 400 kWh per year or more, depending on the size of the pump, size of the household, and water use habits.

Appliance Recycling

The Association of Home Appliance Manufacturer’s (AHAM) data shows that US manufacturers ship nearly 54 million major home appliances every year. When you buy a new appliance, what should you do with the old one? Recycle it! Recycled steel can be used to make new appliances with significant environmental benefits.

The Appliance Recycling Information Center (ARIC) maintains a website (<www.aham.org/aric/aric.cfm>) and phone hotline (1-800-YES-1-CAN) to answer consumer’s questions about appliance recycling. ARIC reports that “discarded appliances are second only to old automobiles as a source of recycled metals, particularly steel. It takes four times more energy to manufacture steel from virgin ore as it does to make the same steel from recycled scrap. Steel is the most abundant recyclable component in appliances, but not the only one. Major home appliances, or ‘white goods,’ also contain other metals like aluminum and copper, as well as recyclable plastics and CFC refrigerants.”

The US Environmental Protection Agency has identified six major benefits of using scrap instead of virgin materials in making new steel:

• 97 percent reduction in mining wastes

• 90 percent savings in virgin materials use

• 86 percent reduction in air pollution

• 76 percent reduction in water pollution

• 74 percent savings in energy

• 40 percent reduction in water use

Proper recycling procedures also encourage proper disposal of harmful substances used in appliances, such as mercury, CFCs and PCBs.

	kWh use	Power cost
Desktop	219	$21.90
Laptop	44	$4.JB
Savings	175	$17.52

Full heat settings (kWh use)	No water temp oost, no heat dr i (kWh use)	Energy saving: (kWh) -	Annual cost savings
390	130	260	$26.00

Incandescent kWh	CFL kWh	kWh savings	Energy savings
1,000	333	667	$67