More homes have central air conditioners instead of window units. They are more efficient, but people use them more often.
Still, Jennifer Amman, the buildings program director at the American Council for an Energy-Efficient Economy, says she is encouraged.
It's great to see this movement, to see the shift in the national numbers, she says. I expect we'll see greater improvement over time. There is so much more that can be done.
Back in 1990, before most homes had a personal computer and multiple other gadgets, average consumption totaled 9,447 kilowatt-hours per household. That slowly climbed to a peak of 11,504 in 2010. But since then, usage has been steadily dropping.