Gadget Prods Homeowners to Cut Energy Use

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.