Immersion cooling of photovoltaic cells in highly concentrated solar beams

Concentrated solar radiation can be utilized to generate electrical power from photovoltaic cells, but concentrated solar radiation increases the photovoltaic cell's temperature. This increase in temperature can lead to degradation of the cell efficiency, and too high of a temperature can damage the cell's integrity. This is particularly important in dish and tower systems where a maximum uniform flux may be difficult to achieve. While a variety of approaches have been used to the keep the cells cool, most are based upon removal of heat from the back (opposite surface of the incident flux exposed surface) of the cell. This thesis reports on an immersion cooling technique for the cells, whereby a coolant is circulated over the front surface of the cell in addition to its other surfaces. An analysis is given where the cells are placed in a cylindrical glass tube, where a liquid is circulated. The impact of the various thermal processes that result from this approach are described herein. A comparison is made to limited experimental data.