University of California, Los Angeles (UCLA)

More efficient cooling methods are needed to reduce building energy consumption and environmental impact. Buildings account for 72% of the nation's electricity use and 40% of our carbon dioxide (CO2) emissions each year, 5% of which comes directly from air conditioning. The refrigerants used in air conditioning are potent greenhouse gases (GHGs) that may contribute to climate change. Because most cooling systems run on electricity, and most U.S. electricity comes from coal-fired power plants which produce CO2, there is a need to increase the efficiency of these technologies and reduce the use of GHG refrigerants.

The University of California, Los Angeles (UCLA) is developing a novel solid state cooling technology to translate a recent scientific discovery of the so-called giant electrocaloric effect into commercially viable compact cooling systems. Traditional air conditioners use noisy, vapor compression systems that include a polluting liquid refrigerant to circulate within the air conditioner, absorb heat, and pump the heat out into the environment. Electrocaloric materials achieve the same result by heating up when placed within an electric field and cooling down when removed—effectively pumping heat out from a cooler to warmer environment. This electrocaloric-based solid state cooling system is quiet and does not use liquid refrigerants. The innovation includes developing nano-structured materials and reliable interfaces for heat exchange. With these innovations and advances in micro/nano-scale manufacturing technologies pioneered by semiconductor companies, UCLA is aiming to extend the performance/reliability of the cooling module.

If successful, UCLA would eliminate the use of polluting refrigerants in air conditioners used in buildings.