It takes 7 billion gallons of gasoline annually to run all the air conditioners of passenger vehicles in the United States, according to the National Renewable Energy Laboratory. That’s 6% of total fuel consumption in the U.S. Meanwhile, simple refrigerant leaks from the units account for 50 million metric tons of carbon emissions each year.
Now, the NREL wants to put a dent in these numbers by improving the efficiency of conventional air conditioners by 33%. Its plan will focus on cars built between 2012 and 2016, with the goal of saving 1.8 billion barrels of oil and reducing greenhouse emissions by 900 million metric tons.
The NREL team will test a thermoelectric air-conditioning system. Basically, semiconductors that produce a hot and cold side when juiced with an electrical current would be placed throughout the car. Turn the current on, and the semiconductors would cool the car somewhat so the air conditioner’s inefficient pumps and condensers wouldn’t have to work so hard. It would also lower instances of refrigerant leaks.
The biggest obstacle will be the scarcity of the material used to make the modules; bismuth telluride isn’t just lying around on the ground. That’s why the team will look at other ways to reduce interior temperature, including the use of solar-reflective glass and paint, which can lower interior temperatures by 35%.
The NREL will partner with Ford on the project because the automaker won a $4.2 million grant from the Energy Department to improve A/C efficiency.
More Efficient Air Conditioning for Cars (Green Inc.)