UC Merced physicist has solar-hot idea for cooling

Posted at 11:41 PM on Thursday, Sep. 10, 2009

Some day, you might unplug your air conditioner and cool your house on a 110-degree afternoon by cranking up the heat from the sun.

In his laboratory at the University of California at Merced, physicist Roland Winston says he is nearing a breakthrough that could make it happen in the next several years.

Winston, an innovator in amplifying sunlight for energy, is putting the finishing touches on a solar-concentration array that heats oil to 400 degrees. The oil's heat will be used to power a chilling unit that produces cold water for air conditioners.

He expects to announce a collaboration with a private company in the next several months to produce a solar air-conditioning unit.

"We want to make it economic and practical," said Winston, who heads a research team at UC Merced. "The key is collecting solar energy no matter where the sun is in the sky. The San Joaquin Valley is the perfect place to do it."

Valley sunshine was his main reason for moving to Merced in 2003 from the University of Chicago. Winston, 73, spent nearly four decades in Chicago making a name for himself in particle physics as well as solar research. He has dozens of patents collected in a lifetime of research.

His peers in the research community say he could have remained in Chicago and finished his career as physics department chairman, a position he had held for several years. But he knew the sunny San Joaquin was a perfect incubator for solar technology.

Jerry Olson, a principal scientist for 31 years at the National Renewable Energy Laboratory in Denver, said he admires Winston's move to UC Merced.

"Over the years, Roland has really made some very significant contributions," said Olson. "But he really wants this world in a better place, so he moved for solar research."

Winston now is the director of the California Advanced Solar Technologies Institute, which received a $2.25 million grant from the UC Office of the President last month to fund solar research over the next five years. The institute includes researchers at both UC Berkeley and Santa Barbara.

Their goal is to make solar energy more affordable and widespread. UC Merced officials said they were fortunate to land a professor of his stature.

"Roland is a major research presence in the field of solar-energy research," said Jeff Wright, dean of the School of Engineering. "His efforts at UC Merced have already produced ground-breaking innovations."

Solar power has long been coveted as a pollution-free energy from a virtually limitless source. But sunlight is not intense enough to generate large amounts of electricity without massive solar panels.

In his work on energizing particles in the 1960s, Winston found a way to amplify sunlight. He concentrated it by using "nonimaging optics," or mirrors that magnify and focus solar energy.

Winston today is widely accepted as the researcher who invented the field of nonimaging optics. But his ideas were initially met with skepticism, until continued research erased the doubts from the scientific community.

The next task was to develop efficient ways to use the amplified sunlight. Winston and others adapted nonimaging optics for use with photovoltaic cells, converting the energy into electricity.

In the past few years, he has worked at finding ways to channel the energy into devices that heat water or oil - so-called thermal processes.

Thermal energy - heat - is actually used to power conventional air conditioners. They start by heating fluid first. Ordinarily, electricity or natural gas provides the fuel. Winston's approach taps sunlight instead.