Heat rises, and, with a little help from scientists, can soar as high as outer space. A team at Stanford University has created a roof-mounted system which cools buildings, without the need for electricity, by incorporating solar panel-like machines that beam heat into the cold expanse of space. This system, known as radiative sky cooling, is seen as an early step to developing a full strength system to cool buildings without the need for an external energy source. This could prove enormously beneficial in dealing with the impacts of climate change (a warmer planet) while reducing its causes (lowering emissions).
Shanhui Fan, professor of electrical engineering at Stanford, and his team have been working on radiative sky cooling since 2013. Their recent research has demonstrated that the radiative sky cooling system is capable of lowering the temperature of flowing water to below that of the air around it. While Fan and his team have specifically harnessed radiative sky cooling for air conditioning purposes, this process is something that occurs naturally. “If you have something that is very cold – like space – and you can dissipate heat into it, then you can do cooling without any electricity or work. The heat just flows,” explained Fan. “For this reason, the amount of heat flow off the Earth that goes to the universe is enormous.”
The primary obstacle to achieving a net-temperature decrease through radiative sky cooling is the heat received from the sunlight. To solve this problem, the radiative sky cooling system at Stanford incorporates panels that are coated with a multilayer optical film, which has the ability to reflect up to 97 percent of the incoming sunlight. Using data gathered from small-scale testing, the Stanford team projected that a full-scale radiative sky cooling system would result in an 18 to 50 percent reduction in the amount of energy needed to cool a building. To further develop the concept, the team has started a company called SkyCool Systems and plans to incorporate their system into refrigeration and air conditioning models, with a particular focus on cooling massive data centers.
Via New Atlas
Images via Norbert von der Groeben and Aaswath Raman