Their flexible perovskite panels have electrodes made of tiny carbon nanotubes. These can generate more power with greater efficiency and at a cost 70% lower than existing solar panels.
Surrey scientists worked with colleagues at the University of Cambridge, the Chinese Academy of Sciences, Xidian University, and Zhengzhou University, China. Together, they built a new kind of two-faced panel (scientists prefer the term 'bifacial'). They used single-walled carbon nanotubes as both front and back electrodes.
These tubes are just 2.2 nanometres across. That is slightly thinner than a strand of human DNA. A piece of paper is thicker than 45,000 nanotubes stacked on top of each other.
The panels could generate over 36 mW per square centimetre – and the back panel produced nearly 97% of the power that the front panel did. That compares to 75-95% for most bifacial panels currently on the market.
Professor Ravi Silva CBE, the director of the Advanced Technology Institute, said:
"The world cannot decarbonise without solar power. Yet that requires much cheaper solar energy than is currently available. Panels that can absorb the sun's energy on both sides are a great way to make the technology more cost-effective.
“We have produced arguably the highest efficiency single junction solar cell to date. Our panels cost 70% less to make than a normal one-sided solar panel. This could significantly modify the market and simplify the architectures required based on perovskite solar cells."