Part I: Do Flat-Screen TVs Consume More Power?

Why is it that there's no such thing as an easy answer to a simple question when it comes to technology? Over the warm holiday weekend we had one of those "green" discussions, as I'm sure so many of you did. The questions posed were simple: Are the new LCD and plasma displays more energy efficient than old CRT screens? And, which is more energy efficient: plasma or LCD? (I'll cover this question in part II of my post.)

The answer depends on many things, including how you use your TV, when you bought it, and—most of all—how TV power consumption is measured today.

First, the question of new flat-screen TVs versus old cathode-ray TVs. Generally speaking, large-screen TVs consume more energy than the smaller-screened CRT-based TVs they replace. And most people are adding TVs. That is, they tend not to replace old TVs with new ones but add a second or third TV. And since TVs consume power even when they're not on, just adding a TV set or two can add dramatically to your power consumption.

A recent report by the BBC found that in the United Kingdom, plasma televisions, which it says are about 50 percent bigger than their cathode-ray-tube equivalents, "consume about four times more energy according to the government-funded Energy Saving Trust." And when looking at the carbon emissions from the power plants, the same group found that old-style TVs produce 100kg of climate-warming C02 per year, while larger, plasma screens will pump out 400kg from the plant. A recent report from Panasonic, makers of both LCD and plasma TVs, said that the new TVs consume more power than older CRTs, but the company is working to get the new TVs to be more energy efficient as fast as it possibly can.

Some of the best research can be found at EfficientProducts.org. The site says that a typical U.S. household watches about five hours of television each day and that there are about 260 million TVs in our homes. They claim that our TVs are responsible for about 1 percent of our nation's electricity production a year (47 billion kilowatt hours). Most of this electricity is consumed when the TV is turned on (90 percent), but the remaining 10 percent is used in standby modes when the set has been turned off. It predicts that unless TV efficiency improves, the rapid growth in TV sales, increased hours of TV viewing, and multiple TVs per household will ultimately contribute to a rise in TV energy consumption by about 50 percent before 2010.

OK, so much for new TVs replacing cathode tubes. It seems the new TVs consume more power. Now what about the different types of flat screens? Do you know which consumes more power? LCD or plasma? Keep reading to find out.