The Oak Ridge National Laboratory and Whirlpool are at work on a more efficient refrigerator that could reduce average energy use by as much as 40%, a report published at R&D says.

According to the lab, researchers are banking on an oil-free “Wisemotion” linear compressor manufactured by Embraco, along with other technologies and materials, to bring down energy consumption to less than 1kwh per day.

By comparison, refrigerators manufactured during the 1970s used between 4kwh and 5kwh per day, and today’s models average about 1.5kwh per day.

With electricity at an average cost of about 12.5 cents per kwh in the United States, that would save a family about $26 a year–not a huge sum. But collectively, the energy savings would be very large.

“If every refrigerator in the U.S. were replaced with the advanced refrigerator design, the projected primary energy savings would be 0.56 quads per year–the equivalent of 100 million barrels of oil,” Ed Vineyard, director of ORNL’s Building Technologies Research & Integration Center, said.

The linear compressor is said to reduce energy losses by matching the compressor pumping rate to the cooling load. LG, an appliance manufacturer, already advertises an energy-saving refrigerator with a linear compressor. But the ongoing research and development announced by the lab also covers “associated components,” which weren’t specified, the report says.

There was no timetable on when the research would produce a market-ready appliance.