Kai Ryssdal: When you get home tonight — or right now, if you’re already there — take a look around for a second at everything in your house that’s plugged in. Stereos, iPods and iPads, televisions, computers, all of it.

And then consider this: Residential electricity demand in this country actually fell the first three months of the year. As Sarah Gardner reports, that’s a problem for power companies.

Sarah Gardner: Even when you adjust for the weather, power demand fell 1.3 percent in the first quarter of the year. That means even with all our laptops and gadgets, we used less electricity. In fact, over the last decade, electricity demand has been leveling off. And utilities don’t know what to make of it, exactly.

Bob Powers: You know, we’ve speculated.

Bob Powers is with Ohio-based American Electric Power.

Powers: You know, customers are feeling the pinch of the economy, they’re feeling the pinch of high gasoline prices and, you know, they’ve decided to pull back where they may.

That’s one popular theory. Another?

Tom Reddoch: Actually, flat-panel televisions are definitely becoming more efficient than their earlier brethren.

Forty percent more, to be exact. Energy researcher Tom Reddoch says we’re reaping the benefits of years of efficiency regulation. Reddoch’s got another theory, though: All those boomerang kids moving back in with the ‘rents after college, relatives combining households to save on the rent.

Reddoch: And as a consequence, we get a net decrease in actual energy use.

Indeed, the government predicts between 2005 and 2020, home power use will have grown less than a quarter of a percent. But analyst Larry Makovich at IHS CERA says don’t count your kilowatts just yet — who knows what power-hungry technology is in our futures?

Larry Makovich: Uh, electric vehicles.

That’s a hint, says Makovich. But utilities would like more certainty so they can decide whether to build more power plants or not.

I’m Sarah Gardner for Marketplace.