IBM Zurich Research Laboratory, Switzerland, has come up with a novel way to cool solar panels, increase their power output , and make drinking water from seawater. The solar cells they used are Concentrated Photovoltaic (CPV) cells, where lens are used to focus light onto the energy generating surface. Reaching temperatures over 120 °C is not unlikely. When hot, the photovoltaic cells work far less efficiently. What IBM has done is create a series of "micro-channels" etched into the surface of the cells and pump water through. Acting like a radiator, or water cooling cpu device, water cools the cells and deposits the heated liquid into a desalination system. There water is heated further, evaporated, and separated from the salt components.
The clean water portion of the system is more of a concept, while the micro-channel solar cells are the core of the research, keep in mind. With the water cooling features, CPV cells have been shown to operate at 70 - 90 °C with up to 5000 times the solar radiation focused on it. Which, according to IBM, is 5 times as much as CPV cells can handle.
No word on the actual returns of the cell, except for maintaining the optimal performance of each CPV cell. Pumping the water through, may in the end, have diminishing returns in practical use.