The United States isn't dialing down the thermostat and turning off the lights quite as it used to. After declining sharply in recent years, energy consumption per US household is leveling off. This trend reflects how energy-use patterns are changing throughout the economy, according to Department of Energy statistics.
Between 1979 and 1981, a combination of recession and high prices caused the typical house dweller to slash energy use an average of 7 percent each year.
But as the economy turned around, people perhaps stopped caulking, installing storm windows, and taking other measures quite so assiduously. By last year, energy consumption per household declined less than 1 percent, says the Energy Conservation Indicators Annual Report, just released by the Department of Energy (DOE).
''Energy prices have been stabilized - that's a big reason why residential consumption is flattening,'' says Barry Cohen, an analyst with the Energy Information Administration.
Meanwhile, home dwellers have continued to turn away from petroleum fuels and toward electricity as an energy source. Electricity provided 21 percent of the energy used in US homes in 1975. Last year its share was 31 percent, because ''the electric heat pump gained in popularity, among other reasons,'' notes the DOE report.
Homes are not the only places where conservation has slowed. US residents are also not conserving quite as much in their offices, on the road, and in factories. Overall, US energy consumption per capita dropped 2.4 percent in 1983 . In the three previous years, it had declined an average of 5.5 percent annually.
Of course, any decline is good news, as the report points out. And since the first oil shock of 1973 Americans have cut way back on energy use. Last year the average US resident consumed 226 million Btus of energy - 21 percent less than was used a decade earlier.
Strangely enough, petroleum's share of US energy consumption is slightly higher today than it was in the '70s. Fifty-four percent of US end-use energy in 1983 came from oil; in 1970 the figure was 50 percent, the DOE says.
Twenty-seven percent of US energy comes from natural gas. Fourteen percent is wrung from electricity, and coal. Other sources account for 5 percent.
And lest you think buildings constructed since 1974 are bound to be very fuel-efficient, consider this: The most energy-thrifty US commercial buildings are those erected between 1901 and 1920, according to DOE.