New tech harvests waste heat from solar power

The novel system cools solar panels for optimum efficiency and redirects the waste heat for reuse

Spotted: When it comes to solar panels, sunlight is obviously essential, but there is such a thing as too much sunshine. In general, photovoltaic panels function best at 25 degrees Celsius. For every degree above this, the average panel will lose around 0.3-0.5 per cent per cent in power production efficiency.

Australian startup Coolsheet has developed a way to harness the waste heat absorbed by solar panels, and increase their electrical generation efficiency. Coolsheet panels fit under PV panels and are filled with a low-pressure liquid coolant, such as water, salt water, or glycol. This is pumped through the panel to reduce the operating temperature of the solar cells, increasing their efficiency by around four per cent for every 10-degrees-Celsius-drop in temperature.

According to the company, the extra electricity generated from cooling the panels can be used to offset the energy used to run the Coolsheet system, potentially making it carbon-negative product. An additional benefit is that the waste heat generated can be used to heat water in thermal tanks for storage, load shifting, or to run water-sourced and hybrid heat pumps. Or, the hot water can be used directly – for instance, in swimming pools.

Coolsheet is a member of the Australian Alliance for Energy Productivity, an independent, non-profit coalition of business and research leaders interested in developing ways to reduce energy usage. The company is currently finalising its move to full-scale manufacturing and raising growth capital.

Solar technology has been advancing rapidly and Springwise has spotted many developments in this space, including AI-designed solar panels and floating offshore solar panels.

Written By: Lisa Magloff