The university's partnerships with manufacturers of solar power systems means access to hands-on research opportunities for students. But their work isn't just low-level intern stuff; their ideas already are being implemented to bring these companies closer to launching economically viable alternative energy sources.
A (Ful)bright Future
Ever wonder what happens to the efficiency of a solar panel when it gets dirty? Recent UNLV engineering graduate Leo Banchik did the dirty work for Amonix.
By testing the company's system on campus, Banchik found that dust on the system's Fresnel lenses decreases performance. As an undergraduate, he helped develop a procedure for monitoring the dirt buildup. He followed up that project by teaming with classmates to design and build an inexpensive device for small-scale solar generators that can improve efficiency by tracking the sun on two axes.
"It's all about leaving the world in a better place than I found it," Banchik says. "Coal's time is up as an energy source. We need to find ways to make clean energy more efficient, and that's what I plan to do." Banchik recently earned a coveted Fulbright Scholarship, which took him to a top research lab in Madrid, Spain, to expand on his work with specialized solar cells.
What's the Efficiency, Kenneth?
When Amonix needed to know the field efficiency of its latest generation of solar lenses, it turned to the UNLV Center for Energy Research (CER) and graduate research assistant Ken Hynes.
The mechanical engineer is young, but graduated at the top of his class in 2009 with several years of practical experience.
"There's currently no research pointing to a device that can measure overall optical efficiency of a Fresnel lens; so, being the first, there's a lot that goes into it," says Hynes, who designed and built a custom measurement system for the lenses used in the Amonix systems. "It's exciting to know that the company will be able to use the information we get to improve the efficiency of its lenses and its overall system."
Hynes' design uses a copper heat collector to capture light from the concentrating Fresnel lens. Water constantly flows through the system and removes the heat while inlet and outlet water temperatures are recorded. By capturing data from the system and running a few established formulas, Hynes is able to determine how much energy is transmitted through the lens and hits the solar cell.
Happiness is a Warm Sun
Remember the high school science project where you'd take a parabolic mirror out in the sun to see how fast you could cook a hot dog? Just south of Boulder City, Acciona Power's Nevada Solar One is using the same idea to generate enough electricity for more than 14,000 homes each year. The company's solar thermal power system uses more than 180,000 mirrors on the 400-acre site to produce electricity.
UNLV's Center for Energy Research has been involved with the project all along the way, from initial work on components that collect the solar radiation to finding better ways to store the heat when the sun's not shining. The CER even set up shop in a 30-plus acre research facility next door to the site to conduct field research and test new technologies.
Currently, center co-director Yi-Tung Chen and engineering undergraduate Sarah Trabia are looking for alternatives to improve the system's ability to store thermal energy. Key to Acciona's system is a special mixture of liquid salts, which gather and store the heat captured from the sunlight. The liquid salts then generate steam to produce electricity.
The UNLV team is working to identify a salt that can remain in a liquid state for longer periods -- especially at night -- and gather a larger amount of thermal heat. Better salts mean better storage and more efficient and economical systems.
Making Solar Research Cool
Not to sound too obvious, but solar panels can get hot. So hot, in fact, that they don't work well. Allison Gray analyzed this issue for Amonix while working on her master's thesis at UNLV and serving as a student research assistant. She helped come up with a simple fix to cool the system and improve performance.
Gray coupled specialized modeling software with onsite testing to isolate and analyze the temperature of an individual solar cell under different weather conditions. She found that more waste heat could be removed from the cell by reorienting the existing cooling units.
"Having the opportunity to work with people in the solar industry and get hands-on experience with utility-scale technology was extremely beneficial," says Gray, now an engineer with the National Renewable Energy Lab in Colorado. "Participating in real solar energy projects gave me experience heading into my career that not a lot of entry-level engineers had."
