Solar panel tech breakthrough generates electricity from rain

‘Rainfall contains abundant renewable energy,’ researchers note

Researchers have come up with a new way to generate electricity with solar panel technology by harvesting the energy produced by raindrops.

The method, proposed by a team from Tsinghua University in China, involves a device called a triboelectric nanogenerator (TENG) that creates electrification from liquid-solid contact.

These are typically used to harvest energy from waves, as droplet-based TENGs (D-TENGs) have previously faced technical limitations that prevented them from working at any significant scale.

By using solar panel bridge arrays, the researchers discovered such barriers could be overcome

“Referring to the design of solar panels in which multiple solar power generation units are connected in parallel to supply the load, we are proposing a simple and effective method for raindrop harvesting,” said Professor Zong Li, who led the research.

“The peak power output of the bridge array generators is nearly five times higher than that of the conventional large-area raindrop energy harvesting. The results of this study will provide a feasible scheme for large-area raindrop energy harvesting.”

A study detailing the breakthrough, titled ‘Rational TENG arrays as a panel for harvesting large-scale raindrop energy’, was published in the journal iEnergy.

“As an important part of the natural energy and water cycle, rainfall contains abundant renewable energy,” the study notes.

“However, this kind of renewable energy lacks effective utilisation today... Therefore, finding a reasonable topology to relieve the inherent constraints of D-TENGs is of great significance for realising the large-scale raindrop energy harvesting.”

This diagram shows what these D-TENG solar panels might look like when harvesting energy from raindrops (Tsinghua University Press)

It is one of a number of promising advances with solar panel technology in recent months, with an Australian team of researchers developing self-healing cells capable of recovering 100 per cent of their original efficiency after suffering degradation from space radiation.

Earlier this week, scientist’s at the US Department of Energy’s National Renewable Energy Laboratory (NREL) unveiled a design for a double-sided solar panel capable of boosting efficiency rates by up to 20 per cent by harvesting reflected sunlight.