You might not expect it, but lighthouses are leading the way to more powerful solar panels in outer space and here on earth. The key is Fresnel lenses, which enabled 19th century lighthouses to focus a beam of light for many miles. Fast forward to the modern era and you’ll find NASA engineers using these lighter, thinner lenses to improve space-borne solar power – and scientists recently used Fresnel lenses to create a miniature photovoltaic system called the SolarVolt that can concentrate the sun’s rays 20 times.
Entech Solar and NASA‘s Glenn Research Center co-developed the SolarVolt system, which uses tiny Fresnel lenses just ten thousandths of an inch thick. These lenses allow the “multi-junction“ solar panel array to absorb concentrated light energy on a much smaller cell area while producing the same amount of electricity as a larger cell area under unenhanced light.
The technology could lead to much smaller photovoltaic plants, or it could greatly enhance the efficiency of the world’s largest solar plants. The revolutionary solar panel technology also won an R&D 100 Award in 2012. Of course, this technology would have never been possible if NASA engineers had not pushed the limits of these lenses.
Previously NASA researchers used comparatively larger Fresnel lenses to boost the effectiveness of the photovoltaics powering the Deep Space 1 mission. The spacecraft’s Solar Concentrator Arrays with Refractive Linear Element Technology (SCARLET) system carried an array of 720 eight-inch lenses to power the first ion engine ever used as a spacecraft’s primary propulsion system.
SolarVolt isn’t the only fish in the ocean, and the competition is intense as solar panels are getting cheaper by the day. NASA engineer Mark O’Neill told Physorg that prices are rapidly dropping, and he believes that multi-junction photovoltaic cells could be economical enough for terrestrial applications in the near future.