Millions of Americans will fire up video game consoles this Christmas, but they may not know that some systems use way more energy than others.

When playing the same video game, Nintendo's Wii system uses a sixth of the power of Microsoft's Xbox 360 and Sony's Playstation 3, according to research from the Electric Power Research Institute.

That doesn't tell the whole story, because the latter two systems have more sophisticated graphics and computing power. That's how Jess Dols, a project engineer at EPRI, explained it.

Dols had the task of playing Madden 2011, a popular football game, on each system for an hour to let EPRI log their relative energy use.

EPRI said if the heaviest gamer plays about six hours a day over a year -- a figure found by Nielsen Co. in 2006 -- then his Wii would consume 29 kilowatt-hours, his Playstation 178 kWh, and his Xbox 360 184 kWh. A plasma TV, by comparison, averages 242 kWh a year.

That makes gaming a formidable energy user. U.S. homes have about 63 million video game consoles, and together they use about as much energy as San Diego does in a year, according to a 2008 study by the Natural Resources Defense Council.

It isn't just killing zombies that uses the juice
Much of the energy use isn't even from playing video games, according to NRDC -- it's from the idling that goes on after the gamer has left the room. The group said idling uses about as much energy as playing.

If gamers turned off their systems when they finished playing, and if manufacturers made systems that turned themselves off when inactive, consumers would save $1 billion a year in utility bills, NRDC said.

But part of the issue is behavior. Today, in many games, turning off a system means the player would lose progress before he can return to it.

And even if game systems come with power-saving features, they're usually not on by default.

In its report, NRDC asked the industry to make games easier to save, to switch off power automatically, and to make sure the consoles are energy-efficient when playing movies, an increasingly popular use.

Manufacturers throw up their hands at pending EPA regs
U.S. EPA is developing Energy Star guidelines for game consoles; this wouldn't set minimum energy standards for them, but it would affix a label to the most efficient models on the store floor.

EPA said it plans to have the Energy Star label ready by the end of 2011.

In the proceedings, the Consumer Electronics Association, the main group representing the U.S. industry, said EPA's current proposal is "simply not achievable."

"Obviously, aggressive and achievable Energy Star specifications for game consoles are desirable," the CEA commented (pdf) last December. "But manufacturers cannot indefinitely sustain the level of energy consumption improvement seen over the past few years."

CEA also said that gaming consoles vary widely; some are mainly for video games, others have features for surfing the Internet or watching movies, so they shouldn't be rated by the same standard.

EPRI found that all three gaming systems' latest models use less power than their predecessors.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500