Best of both worlds: Researchers generate ‘supercritical’ solar steam — enough power to replace fossil fuels

In what could prove to be a monumental discovery in the renewable energies industry, researchers at CSIRO, the Commonwealth Scientific and Industrial Research Organization (Australia's national science agency), have proven they can create pressurized “supercritical” steam using solar energy. 

In fact, in recent tests the group was able to achieve the highest temperatures ever outside of using fossil fuel sources.

CSIRO's Energy Director, Dr. Alex Wonhas, said this mark represents a game-changer for the renewable energy industry.

“It's like breaking the sound barrier; this step change proves solar has the potential to compete with the peak performance capabilities of fossil fuel sources.

“Instead of relying on burning fossil fuels to produce supercritical steam, this breakthrough demonstrates that the power plants of the future could instead be using the free, zero emission energy of the sun to achieve the same result,” Dr. Wonhas said.

Research was conducted at the CSIRO Energy Center, Newcastle, which houses Australia’s low emission and renewable energy research. The Center includes two solar thermal test plants, and features more than 600 mirrors directed at two towers that house solar receivers and turbines. 

For those unfamiliar with supercritical steam, it’s basically water pressurized at tremendous force and heated using radiation. The aforementioned world record set for pressurized steam was actually achieved last month, with a recording of 23.5 megapascals (a measure of force per unit area), and temperatures up to 570 degrees Celsius (1058 Fahrenheit). 

Demonstrating the combination of pressure and temperature at this large of a scale has never been done before, and represents a breakthrough moment for solar power, especially when you consider the fact that today’s commercial solar thermal power plants use subcritical steam, operating at similar temperatures, but lower pressure. If these plants switch over to supercritical steam, it would not only increase efficiency, but help lower the cost of solar electricity too. 

While there is still plenty of work to be done in order to get this technology ready for commercialization, this achievement is something worth celebrating. 

“This breakthrough brings solar thermal energy a step closer to cost competitiveness with fossil fuel generated power,” says Ivor Frischknecht, CEO of the Australian Renewable Energy Agency, in a succinct explanation of why this discovery matters so much to the renewable energies industry as a whole.  

Story via csiro.au