Leaking Electricity

A surprisingly large amount of electricity is consumed by appliances that are actually switched "off" or not performing any immediate service. Building Energy Measurement and Performance Analysis researcher !-- --> Alan Meier, along with Leo Rainer and Steve Greenberg, estimate that the average US house "leaks" about 50 watts as a result of cordless phones, instant-on features on televisions, battery chargers, and a multitude of electronic appliances. Each low-voltage transformer (those ubiquitous "black cubes" plugged in all over the house), for example, consumes a few watts, even when the appliance is disconnected. There are probably around half a billion of these cubes being used in the United States alone.

Meier and his fellow researchers are devising ways to reduce leaking electricity. Part of the problem is due to manufacturers' desires to minimize costs. Manufacturers could easily raise the efficiency of the low-voltage transformers by substituting higher quality steel and other materials. In other cases, they could eliminate the load entirely by moving the "off" switch to the high-voltage side of the transformer.

Many appliances have circuits that require low-level energizing. To address this requirement, Meier, Greenberg, and Rainer designed a circuit that would draw power only when a small, internal battery needed re-charging; the rest of the time it would switch off. Future designs could eliminate the battery by using new capacitors. Such circuits would also be more resistant to power fluctuations (and avoid those annoying flashing digital displays).