Desert sand from UAE efficiently stores thermal energy

ABU DHABI, United Arab Emirates, Jan. 7 (UPI) -- Researchers at the Masdar Institute of Science and Technology in United Arab Emirates have discovered a new solar energy storage material just outside their back door -- desert sand.

Testing shows desert sand from UAE can withstand temperatures up to 1,000 degrees Celsius, making it an ideal solar energy storage material.

"The higher you can push your temperature, the more efficient your plant will be in generating electricity," researcher Nicolas Calvet, assistant professor of mechanical and materials engineering, told The National.

There's more than one way to harness the power of the sun. Most solar energy technologies use photovoltaics, specially layered semiconducting materials that convert sunlight directly into electric current -- no sand necessary.

Another option is a technology called concentrated solar power, or CSP, which uses an array of mirrors to concentrate sunlight onto a single point where thermal energy is stored and converted into electricity. CSP storage structures often take the form of a tall tower -- like skinnier version of a grain silo.

The latest research suggests desert sand could serve an ideal material for CSP technologies -- its quartz and carbonate particles able to efficiently absorb and store thermal energy. It's also readily available.

"The availability of this material in desert environments such as the UAE allows for significant cost reductions in novel CSP plants, which may use it both as TES material and solar absorber," Calvet said. "The success of the Sandstock project reflects that usability and practical benefits of the UAE desert sand."

Researchers are now working on developing a scalable sand-based CSP prototype.