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Cut Your Energy Bills Now

Excerpt from Cut Your Energy Bills Now by Bruce Harley, to be published December 2008. Reprinted with permission of the publisher, the Taunton Press.

Most of us would like to see our energy bills go away, but we don’t spend that much time thinking about them. At the end of the month, we are not proud owners of kilowatt-hours and therms; we pay for the comfort and utility we enjoy in our homes. We pay to keep warm in winter, to keep cool in summer, and to have hot running water. We pay for our toast and coffee, our TV and computer, our answering machine and cell phone charger. Conservation implies sacrifice, or at least a willingness to get by with a little less. Efficiency means enjoying the same level of comfort and convenience using less energy. Conservation usually costs nothing; efficiency typically involves an investment.

Here are some myths about both approaches.

Power surges from turning on an electric device use more energy than leaving the device on. This is a myth born of laziness. The initial power surge from turning on any light, computer, or appliance consumes the same energy as just a few seconds of actual operation. So when you’re not using it, turn it off.

Turning your computer off wears it out, so it’s better to leave it on. This is a holdover from 1980s technology, when hard drives were prone to failure. Modern computers don’t suffer from power cycling. In fact, turning them off or putting them in standby helps them last longer by reducing heat and mechanical wear. With modern energy-saving technologies, and much more stable operating systems, using a standby, sleep or hibernate mode will get you back up and running reliably, much faster than rebooting.

An air conditioner that runs continuously uses more energy. Actually, a smaller air conditioner, with a smaller compressor and fan, running for an hour uses less energy than a larger one running for 20 or 30 minutes at a time. And if you live in a humid climate, longer run times provide more effective dehumidification.

If the outside of my water heater doesn’t feel warm, it must be well insulated. Even on a poorly insulated tank, the outside surface of the tank jacket will be pretty close to the room temperature—that doesn’t mean you aren’t losing a lot of heat. Unless the tank is already internally insulated with foam, it can still benefit from an extra blanket.

If I set back the temperature in my house, it will take more energy to bring the temperature back up. Not true. In cold weather, when the house cools off, the smaller temperature difference means less heat flow to the outside—and that means fewer BTU to buy, even while the house is recovering. (It works exactly the same for air conditioning, but the temperatures are reversed.) The only time the answer is yes is if you have a heat pump with electric backup heat, or if you are so uncomfortable with the lower setting that you overshoot when you are in the house.

My house is dry in the winter because of my furnace. Actually, the dryness is caused by cold, dry outdoor air leaking into the house. Sometimes running the furnace drives air exchange even faster because of leaky or unbalanced ducts.The best solution to dry air is sealing leaks in your house and ducts to reduce air exchange. That will help manage humidity better and more safely than a humidifier.

Duct tape is designed for sealing ducts. Despite duct tape’s name and its status as a superior do-everything product, there’s one place duct tape doesn’t work: ducts. It’s been proven unreliable, and according to building codes, it is actually not legal for sealing ducts. It may be good for 1,001 other things, but for ducts, use duct-sealing mastic.

Heat rises. Actually, warm air rises. And houses tend to leak, especially at the attic—that’s why attics are warmer in winter than they should be. The only reason most people put more insulation in attics than they do in walls is that it is cheaper and easier to put more in the attic, and the myth of heat rising reinforces that thinking. In the summer, cool air sinks, and the upper floor gets hot because the air leaking in is coming from the roof/attic area, where it’s superheated. Sealing attic leaks before insulating prevents air exchange in both directions.

New siding adds valuable insulation. Technically, any layer adds to your wall insulation. But the thin, foam backer board that is typically touted as “extra insulation” is mostly to create a flat surface for the convenience of the siding installer. The visual impact of “adding insulation” is better for customer perception than it is for their energy bills.

My windows and doors cause the most drafts. The biggest air leaks in most homes are hidden in attics, basements, garages and crawl spaces—not around your windows. I know, you sit by the window and feel air moving, but that can be misleading. Often, it’s mostly the “cold” or “hot” surface you feel. Surface temperature affects your comfort dramatically through radiant heat—think about being in a car in the hot sun. Even with air conditioning on, you can feel the heat from the windshield on your hands. You can also feel a “ghost draft” in cold weather. Even with a perfectly airtight window, cool indoor air bouncing off the windowsill can make you uncomfortable.

Read More: Energy Costs Have You Seeing Red? Bruce Harley, author ofCut Your Energy Bills Now, tells you how to save some money.