My recent column on vampire energy -- also known as standby power -- generated well-deserved heat. Standby power is the energy wasted when electronic products are turned off, but plugged into an outlet.
Readers sharply disagreed with estimates that the average household wastes about $1,000 a year in standby power, or $4 billion annually. And they were right. Numbers from a news release were misleading.
The Department of Energy estimates that the average home in the United States ''spends $100 per year to power devices while they are off (or in standby mode),'' according to Christina Kielich, a department spokeswoman. Kielich said that nationwide about $10 billion a year is wasted in all forms of energy.
The average household in the United States spends about $1,247.52 a year on electricity, with regional differences.
Vampire power consumes 5 to 15 percent of the average bill, according to the Department of Energy, but there's considerable disagreement about electricity wasted through standby power. Nonprofit consumer groups and electronics industry experts provide standby energy estimates that range from 10 percent to 75 percent of the average electric bill. One international academic report -- ''Global Implications of Standby Power Use'' by Alan Meier of Berkeley Lab, USA -- places standby power at 1 to 25 percent.
''Standby power also appears to be growing rapidly as more appliances are built with features that lead to standby power consumption,'' according to the report.
Differing estimates may be due to a shifting definition of standby power. The category typically includes energy burned by the small lights, clocks, keypads and internal computers programmed into many devices.
Some industry experts broadly include water heaters and refrigerators, which are constantly running. Additionally, I've also seen calculations that include computers that are in the ''sleep mode'' and battery-charging gadgets that are left plugged into a wall after portable devices have been tucked away.
But what does this mean for the consumer? The Department of Energy recommends that we should look for appliances with the Energy Star label. Additionally, the government recommends using power strips that can be easily turned off when appliances are not used. And, of course, you can simply unplug appliances that are not in use.
Consumer beware: That advice also has critics. It can be time-consuming to constantly disconnect unused devices and to reprogram electronic clocks after every use, some argue.
Conceptually, this sounds like a useful tip.
In practice, the actual savings are minuscule and not worth the effort of constantly plugging and unplugging appliances in, said Michael Gibbons, a reader from Bellevue, Wash.
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