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Set-top boxes are among the consumer electronics that can qualify for an international program called Energy Star, which promotes products that meet certain energy efficiency standards. (Associated Press)

Many high-definition digital video recorders consume more power than the TV they're plugged into, a study by a U.S. environmental group suggests.

Together, a typical household set-up with an HD receiver and an HD-DVR consumes an average of 446 kilowatt hours per year — more than the 416 kilowatts per year used by a standard-sized, energy-efficient refrigerator, reported the San Francisco, Calif.-based Natural Resources Defence Council in a study conducted with Ecos Consulting and released earlier in June.

Guzzlers and sippers

The NDRC study found:

  • U.S. satellite HD-DVRs drew the most power, ranging from 30 to more than 50 watts.
  • IPTV HD-DVRs were the most energy efficient among U.S. devices, consuming as little as 18 watts while on and 12 watts while in sleep mode. 
  • European HD DVRs were far more efficient, using less than 10 watts while on.
  • Apple TV was the most efficient of all devices tested, using three watts while on and less than one watt in sleep mode.

The study, conducted in 2010, measured the energy consumption of 58 kinds of pay-TV boxes in the U.S., a few similar boxes in Europe, and a few video streaming boxes such as AppleTV.

Based on its results, the authors estimated that the 160 million DVR, cable and other pay-TV set-top boxes in U.S. homes consume $3 billion of electricity per year (at an average price of 10 cents per kilowatt hour) or roughly the same amount as the entire state of Maryland, the study said.

The devices draw about two thirds of that power when they're not in use because they consume electricity at nearly the same rate while sitting idle as they do when displaying or recording video content, the study found.

"Hitting the on/off button merely dims the clock or display and instead of having your DVR consume 35 W when on, it consumed 34 W," said Noah Horowitz, senior scientist at NDRC, in an email Monday.

The study estimated that power consumption by the current existing number of set-top boxes could be cut 30 to 50 per cent by 2020 by:

  • Designing boxes that automatically power down to much lower levels when not in use.
  • Using systems that connect one device to multiple TVs, instead of individual systems for each TV.

Energy Star

Set-top boxes are among the consumer electronics that can qualify for an international program called Energy Star, which promotes products that meet certain energy efficiency standards.

In Canada, the program is a partnership between Natural Resources Canada’s Office of Energy Efficiency and the consumer products industry.

NRCan reports that one DVR model sold in Canada uses 284 kilowatt hours per year or roughly $28 worth a year (at 10 cents per kilowatt hour). A similar Energy Star qualified model would use 165 kilowatt hours per year, saving $12 in electricity each year.

The study noted that that pay-TV service providers control box installation, and the consumer has little choice about the model.

"The consumer, who pays the electric bill, deserves technologies without hidden costs," said Horowitz in a statement.

Horowitz said NDRC has been advocating for improving the energy efficiency of consumer electronics because they are one of the fastest growing sources of electricity in the home. As part of that work, the group has been examining the energy use of TVs and the devices connected to them.