French PV system installer Sunbooster has developed a cooling technology for solar panels based on water. It claims its solution can ramp up the power generation of a PV installation by between 8% and 12% per year.

The solution consists of a set of pipes that can surround a rooftop PV system or ground-mounted plant. The pipes are used to spray a thin film of water onto the glass surface of the modules.

Water flow

The company’s solution is a patented pipe with a number of very small holes, so special installation skills are required. Stored rainwater is pushed into a ramp at the edge of the panels. Water then flows onto the surface of the modules and immediately lowers the temperature.

“The materials used to build the pipes have been chosen based on their quality, reliability and durability,” Boutteau said, without providing additional details about the patented technology. “Pipes are UV-resistant and drilled with holes – their number and size are defined by our design and engineering office in respect of our patents.”

The water only spreads across the glass surface of the panels and does not touch any plastic parts, such as the backsheets or other components.  “It can be considered in the same way as rain, and for this reason it does not affect the warranty of the modules,” Boutteau said.

Cost considerations

The technology, which can be applied to PV systems and solar plants built at all kinds of tilted angles, currently costs almost €250,000/MW. But Sunbooster expects to more than halve that to between €100,000/MW and €150,000/MW within the next two years.

“We are now developing new partnerships with big players,” said Boutteau. “And this, combined with the economies of scale of large ground-mounted projects, will help us reduce our costs significantly.”