Masdar and MIT work to increase solar efficiency

ABU DHABI // Masdar Institute researchers are developing a new technique to make solar absorbers more efficient at generating electricity.

Their collaboration with the Massachusetts Institute of Technology (MIT) aims to produce a solar absorber that uses tiny holes to absorb about 90 per cent of the Sun’s rays. The holes are 200 times smaller than the width of a human hair.

If successful, the technique could significantly reduce the cost of using solar power, according to the researchers.

Unlike traditional solar absorbers, the new version requires very little material and consists of only two layers – a semiconductor film and a reflective metallic layer, with a total thickness of 170 nanometres.

“This idea can be applied to most conventional solar absorbers. With this unique patterning, the absorbers can be boosted to harvest more solar energy from the ultraviolet and visible regions of the electromagnetic spectrum,” said Dr Jin You Lu, a postdoctoral researcher at Masdar Institute.

Dr Zhang Tiejun, an assistant professor of mechanical and materials engineering at Masdar Institute, said the research team had developed a simple and cost-effective fabrication technique.

Dr Zhang and researchers from MIT recently co-authored an article on the new technique that could lead to lower carbon emissions resulting from the use of electrical appliances.

Dr Nicholas Fang Xuanlai, professor of mechanical engineering at MIT and co-principal investigator on the project, said the collaboration had led to new insights in the emerging field of plasmonics, the study of how an electromagnetic field and free electrons in a metal interact.

Trapping sunlight in plasmonics could allow the solar absorber to better trap and disperse energy, he said.

“We look forward to testing the overall solar conversion efficiency of the coating materials in the next step of our ­research,” said Dr Fang.