NREL Senior Scientist Gary Jorgensen (right) and SkyFuels Chief Tech Technology Officer Randy Gee
Innovators, 1
December 2009 / January 2010
Volume 7 Number 6
Gary Jorgensen's interest in capturing energy from the sun was first piqued in the 1970s when he relocated from the overcast Eastern seaboard to the sunny West. The young physicist didn't know then that his professional path would lead him to a long and prestigious career in renewable energy, one that in 2009 has included awards for innovative solar technologies.
As a senior scientist at the National Renewable Energy Laboratory in Golden, Colo., Jorgensen was a lead researcher on the teams that developed a cost-reducing solar reflector that is an integral part of the SkyTrough—„ parabolic trough solar concentrating collector, and a weathering system that cuts product testing time—€”the Ultra-Accelerated Weathering System. Both technologies were honored in 2009 by R&D Magazine as being two of the top 100 technical innovations of the year.
Jorgensen's journey into the field of science started at a young age. A homemade Christmas present from his uncle —€”a gadget made of lab glassware that inflated balloons when vinegar and baking soda were added—€”inspired him to learn more about how things worked. That first introduction to basic science led to erector sets, then telescopes, microscopes and chemistry sets throughout his teen years. As an undergraduate student, his fascination with the inner workings of locks landed him a job as a locksmith, which helped pay his way through college.
"I was always interested in finding out how things work," Jorgensen says. "As a scientist, I know there's an answer to everything. But you have to ford the river and find your way to it. You have to put in time and effort to get there. Seeing the end point off in the distance can be the driver that keeps you going."
This same persistence and drive led Jorgensen in 1978 to the Solar Energy Research Institute, a new government-funded organization that later became NREL. During his 30-year stint at the lab, he has worked in the areas of concentrating solar power (CSP), developing and testing optical materials, and photovoltaics (PV), focusing on testing the durability of packaging materials for PV modules. He has also conducted research on the reliability of polymeric glazings and on absorbers for lower-cost solar domestic hot-water systems. In 2008, Jorgensen joined with industry partners to develop materials and support durability testing, as well as to provide optical modeling of advanced CSP systems and develop new characterization tools for determining optical performance. Over the course of his NREL career, he has published almost 150 papers, reports, and key presentations; he holds eight patents, with two others pending.
Two of those patents are for a breakthrough solar reflector film—€”ReflecTech® mirror film—€”used in CSP collectors, including the SkyTrough technology that received both a 2009 R&D 100 Award and a 2009 Excellence in Technology Transfer Award from the Federal Laboratory Consortium.
The SkyTrough is the result of more than a dozen years of collaboration between NREL researchers and industry partner SkyFuel, Inc., a small company headquartered in Albuquerque. Like other parabolic trough systems, SkyTrough concentrates the sun's energy using long, curved reflective surfaces that focus sunlight on a tube positioned along the focal line of the trough. The reflected sunlight raises the temperature of the heat-transfer fluid flowing through the tube to nearly 400°C. The hot fluid is then used to produce steam that drives a conventional steam-turbine generator to produce electricity.
The key difference of SkyTrough compared to the conventional technology is its mirrors. Traditional parabolic collectors use glass mirrors, which are breakable, heavy, and expensive to manufacture. The SkyTrough mirrors are lightweight and glass-free, consisting of ReflecTech mirror film, which is the component that Jorgensen helped to develop. This glossy laminate is composed of multiple layers of polymer films with an inner layer of pure silver, all adhered to a thin aluminum sheet. This composition gives the material a highly reflective surface that also protects the silver layer from oxidation. The mirror film is lighter and less expensive to manufacture than glass mirrors, and it is also much easier to transport and install. This gives SkyTrough the potential to be significantly less expensive than today's best CSP collectors.
Although solar power has been nipping at the heels of fossil fuels for decades, it has yet to find a way to be cost-competitive on a large scale. However, the SkyTrough parabolic collector could be a game-changer, potentially lowering the cost of concentrated solar fields by as much as 30 percent.
"Glass is highly durable, but is heavy and hard to shape without added cost," says Jorgensen, who with SkyFuel chief technology officer Randy Gee developed the ReflecTech mirror film. "Once industry sees the advantages of the silver polymer and is convinced the product is durable in an outdoor environment, the sky is the limit."
A prototype SkyTrough is capturing the sun's rays now atop South Table Mountain overlooking NREL's campus; a larger pilot system has been installed at SkyFuel's research and development site in Arvada, Colo., a few miles north of NREL. The troughs could be installed within several months in the sunny Mojave Desert region of California, and soon, in Arizona, Nevada, New Mexico, Texas and Colorado, which are states blessed with abundant sunshine and vast open areas.
The second 2009 R&D 100 Award with which Jorgensen was involved honors the Ultra-Accelerated Weathering System (UAWS), an ultraviolet concentrator dish used to weather materials.
The dish is a multifaceted UV solar concentrator that speeds up the exposure of coatings, paints and other materials to determine their durability and resistance to sunlight and weathering. Solar industry applications include testing coatings used for solar panels and polymeric glazing, absorber and reflector materials. Other uses for the UAWS include paints or finishes used on homes, cars, or bridges. The dish's design allows researchers to accumulate the equivalent of one year's worth of UV weathering in as little as one week, providing test results 12 times faster than other accelerated weathering systems. Now product manufacturers can find out in 10 weeks what their new paints or new anticorrosive materials will look like in 10 years.
The UAWS is the outcome of a cooperative research and development agreement among NREL, the Russian Institute of Laser Optical Technology and Atlas Weathering Services Group, a material testing solution center in Arizona that is NREL's industry partner. The seeds of the idea for the new system go back almost 15 years. In the mid-1990s, NREL was involved with a national consortium trying to address a critical industry need: highly accelerated testing to allow companies to predict with confidence what the service-lifetime guarantee should be on their products.
"What's been done in the past is the Rip Van Winkle approach to materials testing," Jorgensen says. "You put a product on exposure outdoors and go to sleep for 20 years. You wake up and see how long it lasted. It occurred to me that at NREL we already had a high-flux solar furnace that could provide exposures of 2,000 suns."
Working with the Russian team, Jorgensen and other NREL researchers configured existing components to make the solar flux of the furnace more uniform, shining rays evenly at a more manageable intensity of 50 or 100 suns over test products.
NREL's main focus for the UAWS will be on aging materials for CSP and solar-heat applications, but testing could expand to other solar materials, such as for PV applications. The UAWS will be used in collaboration with a similar UV dish installed at Atlas in Phoenix to verify exposure data correlations for organic materials including paints, automotive coatings and PV packaging materials.
The dish also is expected to be a hit with the aerospace and electronics industries, Department of Defense, and designers of anticorrosion materials for bridges and buildings. "Anything that is expected to last in an outdoor environment could benefit from the accelerated testing," Jorgensen says.
Looking forward to the future of renewable energy, Jorgensen predicts a broad-based approach will be taken. "In 50 years or so, I think a long menu of renewable technologies will be required to supply our energy needs," he says. "We'll see a vast array of systems in use, including photovoltaics, wind, biofuels, concentrating solar power and probably nuclear."
Jorgensen hopes any lingering doubts about the need for renewable energy will have disappeared by then. "There are misperceptions in some of the media and among some of the public that the negative impacts of carbon emissions and climate change aren't real, or aren't a serious problem," he says. "We need to overcome that. In general, scientists don't like to stand up and yell. We present facts. And the facts exist concerning the need for renewable sources of energy."
After more than 30 years in the renewable energy field, Jorgensen is as fascinated to discover how things work as he was when he was a boy. But now his interest is richer and deeper. "I've received a lot of support from colleagues and my family along the way. I hope that maybe I can make a positive change in the world. For me, there are select fields of endeavor that can make a difference and improve society for future generations, and renewable energy is one of them."
Kathryn Ruckman is a writer in the NREL communications office.
Copyright © 2012 | Innovation America