It still doesn’t seem as if consumers give much - if any - weight to power consumption when they choose a large-screen TV. But various power authorities care, regulatory agencies are getting interested, and the companies that generate and distribute electrical power care a lot. Trade associations are also paying attention.

Ken Werner
Senior Analyst and Editor

The Consumer Electronics Association commissioned a report on power consumption by consumer electronics devices, which was delivered this past January and is available on the CEA website at http://www.ce.org/pdf/Energy%20Consumption%20by%20CE%20in%20U.S.%20Residences%20(January%202007).pdf. The report’s authors determined that the 237M "standard analog" TVs in operation in the U.S. in 2006 consumed 53 terawatt-hours of energy and accounted for 1.4% of the electrical energy consumed in the U.S. that year. Almost 60% of these TV sets had screen sizes between 19 and 31 inches, and the average set consumed 115 watts. An additional 40M sets were something other than "standard analog," so in 2006 flat-screen TVs were not yet having a major impact on U.S. power consumption.

But they will. Recently, CNET measured the power consumption of 54 television sets. Flat-panel TVs with 42-inch screens ranged from about 190 watts to 250, with most clustering between 200 and 230. Not surprisingly, larger TVs consume more power. CNET measured the power consumption of a 65-inch Sharp LCD-TV as 584 watts.

If you care about managing TV power consumption - as a volume purchaser, government regulator, or individual consumer - you have to have a way of directly comparing the consumption of different TV technologies. This has been difficult to do because different display technologies consume power differently depending on the program material being shown. For instance, emissive displays such as plasma and OLED create light at a pixel location only when light is to be seen at that location. LCDs act as shutters at each pixel location that pass or block light from a backlight that is - in conventional LCD-TVs - always on. Therefore, an emissive display will consume much less power on darkly lit program material (such as the movie Sin City) than on brightly lit material. Conventional LCDs, on the other hand, consume about the same amount of power regardless of program material.

A working group of the International Electrotechnical Commission (IEC) is now refining a power measurement standard that uses a DVD containing a mix of program material that represents an average of what television stations broadcast. Larry Weber, a member of the IEC working group, tells me the U.S. Environmental Protection Agency (EPA) is proposing to base a TV Energy Star specification on this DVD.

So, are panel makers listening? You bet. On Saturday, Nikkei reported that six companies - Sharp, Sony, Hitachi Displays, Tokyo Electron, Shibaura Mechatronics and V Technology - are performing cooperative research on energy conservation technologies that can be applied to LCD televisions, and that they have obtained ¥700M in subsidies from the New Energy and Industrial Technology Development.

Specifically, Nikkei reports, "the firms plan to develop technology related to equipment for producing advanced thin-film transistors for use in large displays. Also, they will try to come up with a more energy-efficient LED (light-emitting diode) backlight. The companies aim to devise technologies that will enable them to halve the electricity consumed by a 40-inch TV by fiscal 2011." Half the power is also what Sharp has announced as the specification for the super-slim 52-inch LCD it will produce at its new Gen 10 fab beginning in March of 2010.

Plasma makers are also reducing the power consumption of their panels. At least one manufacturer has predicted that one of its new models will have a luminous efficiency of 3 lumens per watt, up from a little over 2 for most recent panels. And Samsung recently announced it was the first company to apply power-saving single-scan driving to a Full High Definition plasma display.

So it seems that everybody cares about power consumption except the consumer - and, therefore, the set makers. At trade shows, specification cards by panels and TV sets frequently list the unit’s power consumption. But if you poke around on the web for the specifications of specific TV sets, you will be hard pressed to see a spec for power consumption.

But power consumption is not like trans-fat. If a high trans-fat content is listed on a package of frozen French fries, a significant number of people won’t buy it. But are consumers in developed countries likely to care if their large-screen TV consumes the same amount of power as 3 light bulbs, even if it’s clearly stated on the box? Probably not. However, in the aggregate, the power consumed by those large flat panels becomes a significant issue. That’s why regulatory agencies have no choice but to become involved. In the U.S., look for the EPA to issue its TV Energy Star spec in mid-2008.

For more on the new IEC power-measurement standard and method, see the next issue of Projection Monthly with Enhanced Flat Panel Coverage.

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