In a typical household in the U.S., the television is on for eight hours each day, according to Consumer Reports. Some of those TVs use more energy than a refrigerator. (See Reference 1) In 2009, concerns about the electricity consumption of big-screen televisions prompted California to consider banning some models. (See Reference 2) How does the energy consumption of a big-screen TV compare to that of older cathode-ray tube televisions?
The traditional CRT is used by some projection models. Flat-screen televisions use plasma or liquid crystal display (LCD) technology. Although the two types often get lumped together under "flat screen," plasma and LCD differ greatly in their energy consumption. A 37-inch LCD uses about the same energy as a 36-inch CRT television, but a plasma TV uses more energy than a similarly-sized LCD. The type of television has less impact on the amount of energy used than the size of the TV's screen. (See Reference 1)
Size vs. Resolution
Large-screen televisions use more energy than smaller models. In a Consumer Reports study, 50-inch plasma TVs consumed two times as much energy as the largest CRT model, which measured 36 inches. The 50-inch plasma used slightly more energy than a similar-sized LCD model. However, two plasma televisions of the same size but different resolutions use radically different amounts of energy. The 720p model used more than 30 percent more electricity than the same-sized 1080p model. (See Reference 1)
Energy Use When Turned Off
Contrary to popular belief, many electronic devices draw energy even when they are turned off, and televisions are no exception. Big-screen TVs may use as many as 13 watts of electricity, although average draw when off is less than two watts. Some rear-projection models draw as many as 48 watts, although the average is about seven watts. (See Reference 3) The amount of standby consumption varies depending on the settings, make, and model of the television.
LCD televisions are generally the most energy-efficient flat-screen technology. Check the TV's Energy Star label to determine the makes and models that use the least amount of electricity. (See Reference 4) Websites such as Top Ten USA (See Resources, below) rank sets by energy use. Among the most energy-efficient televisions, according to these ratings, are LCD models from Sharp, Samsung, and LG.
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