Scientists At The Australian National University Set Solar Thermal Record

Australian National University (ANU) scientists have set a world record for efficiency for a solar thermal dish generating steam that could be used for power stations.

Scientists at ANU designed and built a new receiver for the solar concentrator dish, halving losses and achieving a 97 per cent conversion of sunlight into steam.

This solar thermal dish generating steam could lead to the generation of cheaper base-load electricity from renewable energy and help lower carbon emissions which cause global warming.

“When our computer model told us the efficiency that our design was going to achieve, we thought it was alarmingly high,” said Dr John Pye, from the ANU Research School of Engineering. “But when we built it and tested it, sure enough, the performance was amazing.”

Concentrating solar thermal systems use reflectors to concentrate sunlight and generate steam, which can drive conventional power station turbines. It can be combined with efficient heat storage systems and can supply power on demand at a significantly lower cost than solar energy from photovoltaic panels that has been stored in batteries.

Ultimately the work in this project is all about reducing the cost of concentrating solar thermal energy. Our aim is to get costs down to 12 cents per kilowatt-hour of electricity, so that this technology will be competitive,” Said Pye. He further added “his new design could result in a 10 per cent reduction in the cost of solar thermal electricity.”

Dr. Pye is optimistic that the new technology can play a role in the grid, by helping to provide power at night without fossil fuel power stations running.

The ANU solar concentrator is the largest of its kind in the world at 500 square metres. It focuses the power of 2,100 suns onto the receiver, through which water is pumped and heated to 500 degrees Celsius.

Scientists note that the new receiver design is a cavity that resembles a top hat with narrow opening and a wide brim. Water pipes spiral around the underside of the brim and up into the hat. The receiver design was presented at the SolarPACES 2015 conference.