Supercomputer water-cooling comes to solar power

Solar power outfit Airlight Energy has borrowed technology from the world of supercomputers to make its large-scale photovoltaic collectors more efficient, on the way heating water to get a second source of energy.

As explained by the IEEE, the Swiss company has created a spin-off called Dsolar to develop its dish-style large-scale collector, which uses elliptic reflectors to concentrate solar energy onto high-efficiency multi-junction solar cells.

Those cells need cooling to operate at their best over a long lifetime, and here's where technology from IBM's work in supercomputer cooling comes into play. IBM Research explains rather than just soaking the solar cells, Dsolar uses an approach Big Blue applied to its German SuperMUC machine: micro-channels are etched into a layer of silicon that “wicks” heat away from the cells.

As well as maintaining the efficiency of the cells and giving them a predicted life of 25 years, the water returns at a temperature of 90°C, making it useful in its own right. Bruno Michel of IBM Research in Zurich told IEEE Spectrum the hot water is suitable for some types of desalination plant, or to drive air-cooling machinery.

At full sun, the article claims, the Dsolar unit produces 12 kW of electricity and 20 kW of heat.

There's a couple of other wrinkles in the system worth mentioning. To keep the costs of the structure down, the dish is mostly made of a specialised concrete because it's much cheaper than aluminium or steel. Concrete also has the advantage that it can be manufactured on-site ; and instead of glass mirrors, the light is concentrated by plastic foil.

Airlight Energy is working with IBM Research to bring the technology to market, which it hopes it will achieve by 2017.

In the promo video below, IBM Research says the system can concentrate the Sun's energy 2,000 times, and turn 80 per cent of that into electricity. ®

Youtube Video