passive cooling system

Caption:Two samples of passive cooling devices were tested on the roof of MIT's Building 1: On the left, a sample of the new system, combining evaporative cooling, radiative cooling, and insulation. On the right, a device using just evaporative cooling, for comparison testing. Credits:Photo: Courtesy of Zhengmao Lu
New passive cooling system relys on evaporation and radiation not electricity
Heating and cooling all from one system with no electricity needed
Computer Cooling System Could Save U.S. $6.3 Billion in Electricity a Year