Spain's ULMA Agrícola consortium and Tecnalia research center have developed a new type of photovoltaic solar panel for greenhouses that can generate electricity without an adverse effect on the crops grown within, while additionally providing cooling in summer. The system is designed to exploit the annual oscillation - the variation in the height of the sun's path across the sky over the course of the year. In theory, no solar radiation is compromised over winter, but surplus radiation can be diverted to electricity-generation during summer.
The photovoltaics use optical lenses rather than a mechanical means of solar-tracking, which may generate 15 percent more electricity over a standard photovoltaic system according to the first phase of testing during summer. A second phase of winter testing ending in March is currently underway, and UMLA Agrícola is projecting that similar results will be seen.