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The Greening of Television

Your giant LCD uses just as much energy as your old CRT. That's about to change

2 min read

Sony Bravia ECO TV

1.Backlight A bank of hot cathode fluorescent lamps (HCFLs) in the backlight consumes as little as half the power of a conventional, cold-cathode set. (HCFLs are larger than cold-cathode fluorescent lamps and have shorter life spans.)
2. Audio Only A sound-only mode allows listening from another room or using the TV for audio-only programming.
3. Ambient LightingA light sensor matches the television’s brightness to the room’s lighting—bright to compete with daylight, much dimmer for a darkened room.
4. Sleep Mode A motion sensor in front of the television turns the screen off if no motion is detected for some specified period, then turns it on again when the viewer returns.
5. Mechanical On-Off Switch An Energy Star–compliant LCD television must draw no more than 1 watt when the television is not on, to let it respond to the remote. Turning this switch to “off” cuts that to zero.

That big liquid-crystal display in your new TV may be twice as efficient as the old cathode-ray tube was, but because it’s much larger, it may be using as much energy as your old set—or even more.

Blame that profligacy, in part, on the Energy Star 2.0 efficiency guidelines set by the U.S. Environmental Protection Agency back in 1996. Although they limited to 1 watt the power a TV could draw in standby mode (what most of us think of as ”off”), they didn’t bother counting the watts when TVs were operating. That’ll change in 2010, the effective date of Energy Star 3.0, which calls for cutting the draw of a 42-inch (107-centimeter) TV from 208 W to 115 W. Come 2012, it’ll drop to a mere 81 W.

Energy Star guidelines are voluntary. But on 18 November of last year, California became the first U.S. state to set mandatory limits on the energy consumption of TVs; those that don’t meet California standards cannot be sold in the state. Under the standard, a 42-inch television will be limited to consuming 183 watts by 2011 and 115 watts by 2013.

Most LCD manufacturers already meet or exceed the Energy Star targets, and they are coming up with all sorts of ways to cut back on power consumption, like automatic backlight dimming and video mute. (And some old features, long lost, are coming back again, like the mechanical on-off switch. Without this feature, the TV is always in standby mode and consuming power, albeit just fractions of a watt.)

Lots of new models are touting green features. Sharp’s 32-inch green TV, Aquos DH77, claims an average operating consumption of 55 W and a low-power standby option of 0.6 W, thanks to what it calls the eco-button on the remote (essentially a dimmer switch.) LG’s new entry-level high-definition television, the LH 30, consumes between 55 and 127 W, depending on the mode of operation, which the company contends makes it the most energy-efficient 42-inch LCD to reach the market so far. In June, Vizio announced the EcoHD line of TVs, which beat Energy Star 3.0 by 25 percent. Samsung plans to have all its 37-inch and larger LCDs backlit with LEDs rather than fluorescent tubes by 2010 and is forecasting a 2010 average power consumption that’s 50 percent lower than that of its 2008 TVs.

Perhaps the greenest of the green is the Sony Bravia Eco TV. It packages all of Sony’s eco-friendly features into one unit. A 40-inch Bravia, when on, draws 90 W, which is on the low end for an LCD television of that size, says Katharine Kaplan, EPA team leader for Energy Star product development.

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