By Katherine Salant
Saturday, January 26, 2008

Most of us think of home energy savings in terms of products, prices and percentages.

For instance: A compact fluorescent light bulb costs about five to 10 times as much as a standard incandescent bulb, it uses about 75 percent less energy, and it lasts eight to 10 times longer.

But you can also save energy and money simply by getting more information. That means determining the amount of electricity used by all the equipment in your house. This can frequently be significantly reduced.

The trick is getting that information. It sounds easy until you start to think about it. If you're like most homeowners, you have no idea how many kilowatt-hours you use a month, let alone which things use how much. Moreover, your electricity bill arrives four to eight weeks after the fact, so by then whatever you did to make those numbers go up or down is history.

In the past, trying to measure the power draw of different appliances was an exercise in frustration. You could get plug loads (the power draw of everything that plugs into an outlet), but you couldn't measure anything hard-wired (things with no outlet, such as ceiling lights) or anything on a 220-volt circuit, such as your water heater.

Digital monitors, which became available a few years ago, overcome those challenges. These handy devices, which receive a signal transmitted from a second piece of equipment attached to your electric meter, provide instant feedback on your electricity use and its cost. The monitors, which can be carried to any room in the house, do not indicate the power draw of a specific item. But you can easily figure it out by watching the numbers go up and down as you turn a light fixture or television on and off or stand by the refrigerator as it automatically switches on or off.

Pilot projects in the United States and Canada have shown that homeowners who used these devices quickly connected the dots about what they were doing, how much electricity was being used and how much it cost. Then they started to trim those kilowatt-hours and save money.

The monitors that the Ontario utility Hydro One gave to 400 households in 2004 provided an impressive amount of information. The homeowners could see their total electricity draw and its cost in real time, as well as running totals for the current billing period, and the predicted totals for the period, based on past use.

Homeowners could also see the amount of carbon dioxide they were contributing to the atmosphere in real time, as well as running and predicted totals for the billing period. (Carbon dioxide is the major component of the greenhouse gases that cause global warming. It is produced when fossil fuels are burned to generate electricity.)

The 400 households were followed for 12 to 18 months. Using the monitors, they reduced their electricity use by an average of 6.5 percent, said Dean Mountain, an economist at Ontario's MacMaster University who analyzed the data for Hydro One. Though not huge on a per-household basis, a reduction of this size in every household in Hydro One's Ontario service area would allow the utility to mothball two generating stations, Mountain said.

Which information affected household behavior the most? Mountain said that the cost figures were the clear winners, although "moral suasion" and knowledge about carbon dioxide emissions influenced some people.

In two subsequent, smaller samples in British Columbia and Newfoundland, Mountain said the cost factor was even more compelling. In Newfoundland, where electricity costs are higher and incomes are lower, the households reduced their electricity use by 18 percent. In British Columbia, where electricity costs are lower, incomes are higher and the climate significantly milder, the reduction in electricity use was only 2.7 percent.

Danny Parker, principal research scientist at the Florida Solar Energy Center, conducted a similar two-year study of 17 households in central Florida. His results were similar to Hydro One's. With the information from wireless monitors, the households reduced their electricity use by an average of 7.7 percent. The motivations were also similar: Most households cared more about saving money than about saving the environment, Parker said.

Although Parker's sample was small, it did have an important advantage over the Canadian ones. He had contact with each household and learned in some detail what each did to reduce energy use.

The two households that saved the most electricity -- 14.5 and 17.5 percent -- were unusually motivated to make big changes. In one case, the family broke a major Florida habit: They stopped running their pool heater 10 to 12 hours a day and started using it only when they knew they would be swimming, which turned out to be only a few hours a week. They also replaced their incandescent light bulbs with compact fluorescent ones and beefed up their attic insulation to lower their air-conditioning load.

In the other households, owners focused on smaller gestures such as "turning stuff off," Parker said, adding that although this sounds inconsequential, it does make a difference. "Fifty watts here, 100 watts there -- all those little bits can add up quickly," he said.

In every house, Parker found that "turning stuff off" produced some unexpected "crazy thing." One family discovered a long-forgotten, institutional-type chilled water fountain in the far corner of their garage that used "much more electricity than a refrigerator," he said. In his own house, Parker discovered that his wife's pottery wheel motor had accidentally been left on for three months.

Although Parker has been studying household energy use for nearly 30 years, he encountered a few surprises. One was how much electricity is used by gas appliances: Gas dryers have electric starters, and newer gas stoves have electronic ignitions instead of pilot lights. Another discovery was the amount of electricity used in home entertainment areas, home offices and garages by appliances that were already turned off. Some items used nearly as much power in the "off" position as they did "on." At Parker's suggestion, the homeowners added a power strip in these locations. Although a TiVo must be kept on, Parker pointed out that homeowners can still plug their television, speakers and DVD player into a power strip.

In Parker's house, which he monitored but did not include in his study, he reduced electricity use by 26 percent. Even though most homeowners who get a monitor are not likely to become that enthusiastic, he admitted, energy saving has now become his "professional hobby."

Katherine Salant can be contacted via her Web site, http://www.katherinesalant.com.

Copyright 2008 Katherine Salant