The numbers affirm a long-term energy efficiency trend documented by the Energy Department. For the first time in decades, less than half of household energy use is now devoted to heating and cooling.
"The general trend over time has been that a decreasing share of household energy is used for heating and cooling," said Berry, whose detailed survey is compiled every four years.
Heating and cooling declined as a share of household energy consumption from 58 percent in 1993 to 48 percent in 2009. Energy consumed on appliances, lighting and electronics - all those flat-screen TVs - has increased from 24 percent to 34 percent.
Households devote about 18 percent of their energy to water heating. That portion has remained steady in the last 20 years.
The EIA's numbers are national averages. There are significant regional differences in energy consumption - residents in Northeastern states consume about 47 percent more on average than a household in the West.
The average U.S. household spent $2,024 on domestic energy expenses in 2009. The numbers were highest in cold states: Residents in the Northeast spent $2,595 a year, $1,027 more than residents in Western states.
New Jersey households, which tend to occupy more space than average, consume more energy (127.4 million Btus) than any state other than Illinois.
New Jersey households also consume the most energy among the 16 largest states, whose numbers were broken out separately: $3,065.
The shift in how energy is consumed in homes has occurred even as per-household energy consumption has steadily declined. But electricity has grown as a share of the total household pie.
Electricity and natural gas now account for equal amounts of the energy consumed on site in U.S. households. But it takes nearly three units of energy from primary fuels such as coal, natural gas, and nuclear fuel to generate one unit of electricity, so increased electricity use has a disproportionate impact on the amount of total energy consumed.
The typical U.S. household consumed 11,320 kilowatt hours of electricity in 2009, about two-thirds of which was used for appliances, electronics, and lighting.
Contact Andrew Maykuth at 215-854-2947, @Maykuth or amaykuth@phillynews.com.
