Cooling of Concentrating Photovoltaic Cells Using Heat Pipe Technology

The U.S. Department of Energy has started a new Solar America Initiative (SAI) to accelerate the development of advanced photovoltaic (PV) systems. Significant technological advances have been made in the area of multi-junction solar cells for concentrated PV systems. Because these cells typically are suspended at the focal point of the reflecting mirror, the support structure must provide the both mechanical stability and positioning accuracy, without shading the mirror. Additionally, the structure must incorporate a heat sinking or cooling mechanism to prevent the solar cell from overheating and immediate failure. This project will develop a reliable, effective, low-cost, heat-pipe-based thermal management solution. The heat pipes can be used to keep the solar cells cool by accepting excess thermal energy and transporting it through thin tubular structures to a remote location for dissipation through a natural convection heat sink. Further, the use of heat pipes adds a level of design freedom that can be exploited to perform several key functions (e.g., mechanical positioning, structural support, thermal management, remote heat sinking, and high heat flux capacity). In Phase I, thermal/mechanical requirements will be defined and trade studies will be performed to quantitatively define the cost/benefit relationships of various design concepts. The most promising concept(s) will be fabricated and tested. Commercial Applications and other Benefits as described by the awardee: Concentrating photovoltaic systems can be used as both distributed energy generation systems for remote location use and as multi-megaWatt solar power generating systems in favorable solar areas. The heat-pipe-based thermal management system should enable cost-competitive, renewable, solar energy production. Benefits include energy independence, reduced global warming, and increased technology-based employment.