A breakthrough blending thermodynamics and stargazing, engineers at the University of California, Davis have created a device that generates mechanical power at night by harnessing the temperature difference between Earth’s warmth and the chill of deep space. Developed by Professor Jeremy Munday and researcher Tristan Deppe, the compact Stirling engine uses a heat-radiating panel to interact with space’s extreme cold while drawing warmth from the ground.

When placed outdoors at night, the device produces up to 400 milliwatts of mechanical power per square metre, enough to power a small fan or charge a motor. The invention holds promise for off-grid ventilation in greenhouses or homes in arid regions with clear skies. UC Davis has filed a provisional patent to turn nighttime cool into a reliable energy source.