Cooling panels for buildings send heat into space

US scientists developed an optical surface that allows a natural cooling process to reduce reliance on air-conditioning systems.

Low energy refrigeration and air conditioning is being tested via a group of Stanford University scientists’ optical surface cooling panels. Radiative sky cooling is a natural process that happens as soon as molecules release heat. The heat travels upwards, eventually reaching space, where the vast cold absorbs it. The panel design has been in development since 2013, with a recent update being the successful test of an optical film that reflects light, allowing the natural cooling process to take place even on sunny days.

On a test site in Los Angeles, the team was able to cool running water by three to five degrees Celsius, contributing to an 18 to 50 per cent reduction in the building’s electricity use. With refrigeration and air conditioning sending vast amounts of greenhouse gas emissions into the atmosphere, large scale, low energy cooling solutions could have a significant impact on slowing the rise of the planet’s temperature. This is particularly important as data centers continue to increase in number and size.

Finding smart new ways to reduce wasteful use of energy, especially temperature regulation in homes and businesses, is crucial to creating carbon-neutral communities. A graphene-based wall paint that improves insulation and magnetically-cooled fridges for commercial use are two innovations helping to do this. How could cooling solutions be made dual-purpose with the excess heat used elsewhere?