Solar Energy Scientists Descend On UC Merced

Blake Ringeisen stood out at a conference where much of the discussion centered around chemistry and physics. The tall, lanky and bearded graduate student researcher at University of California, Davis, provided the real-world perspective of concentrated solar energy when he showed that a simple solar fruit dryer can change the fortunes of farmers in east Africa.

In a region without electricity and refrigeration, Ringeisen's master's thesis, drawings of which were displayed at a solar research symposium at UC Merced, means that farmers who barely scratch out a living in Tanzania can preserve more of their harvest.

Without the dryer, up to 80 percent of their crop goes bad before it can be sold. With it, more tomatoes are dried faster and sold at higher prices, even during the off season, which means more money for farmers in underdeveloped nations.

Ringeisen tested two prototypes. He kept the designs simple - few moving parts, wood frame and polished aluminum surface - so that one or two people could build and move them using materials found in that region. One dryer had a concave design; the other was W-shaped. Both were built for $40 or less.

Both were effective, but the concave design was a little cheaper to build and dried tomatoes faster. The research showed once again that solar power can be a game changer in many places of the world, especially where electricity is unavailable or unreliable.

Solar power can help solve world problems, as noted in this Merced Sun-Star recap of the UC Merced symposium, and its use is likely to become more widespread as solar cells become cheaper and more efficient. There are some pretty impressive minds attempting to accomplish that, including some at Merced, which is fast becoming a leader in solar research.

Students and researchers from UC campuses in Merced, Berkeley, Davis, Santa Barbara and San Diego, and other universities, are working hard to improve the efficiency of solar cells. Costs are dropping "spectacularly," said Sarah Kurtz, interim director of the National Center for Photovoltaics and principal scientist at the National Renewable Energy Laboratory.

Meanwhile, the industry is expanding at a robust rate. Photovoltaic shipments are doubling every two years, and costs are falling.

Today, researchers are developing solar cells that are at least 40 percent efficient. Kurtz said 50 percent is possible as economies of scale, new approaches and advancements take hold. "The challenge is to make high efficiency with low cost and high reliability," she said.

Many researchers are focusing on making thinner cells that concentrate light in smaller spaces and have the potential to change the market. Meanwhile, the California Energy Commission is boosting research through its Public Interest Energy Research (PIER) program, which helps finance projects related to research in clean energy and energy efficiency. The agency estimates 2,128 Californians were working in early 2011 in jobs directly related to active PIER-funded research, and more than 3,000 other jobs are indirectly related.

PIER funds have aided efforts at UC Merced, where a grant for $75,000 led to the creation of a business in San Jose that has 180 employees and $100 million in investment. Another research grant from PIER for solar thermal technology was the catalyst for two start-up companies.

"We are looking for breakthrough technology," said Prab Sethi, senior project manager at the California Energy Commission.

Breakthrough technology or industrial revolution? Technology is advancing so fast, it's hard to decide.

(Photo of UC Merced solar symposium by Veronica Adrover of university communication)