3 teens invented a salt-powered refrigerator that doesn't need electricity. They're building 200 of them for hospitals to use.

The sub-zero temperatures quickly freeze the water into the conical structure, so that a mass of ice begins to grow. The end result has the same high, narrow dome-shape typical of Buddhist shrines, hence the “stupa” part of the name, which slows down subsequent melting because the surface area exposed to the sun and warm temperatures is minimised.

intrigued by windows that use so-called smart glass, which automatically turns darker when the room needs to be cooler and lighter when it needs to be warmer. New

King said that in addition to deep emissions reductions—“without that, frankly, we’re cooked”—the center was created to promote research into carbon removal and technologies to “refreeze” the poles. One idea he mentioned was an Arctic version of cloud-brightening. According to this scheme, a fleet of ships would be dispatched to the Arctic Ocean to

two companies are working on invisible, plant-based coatings that extend the life of fruits and vegetables; they’re edible, and they don’t affect the taste at all. Another has developed a “smart bin” that uses image recognition to track how much food is wasted in a house or business. It gives you a report on how much you threw away, along with its

When the warmer, arid growing season arrives, the lower altitude streams quickly dry up and there is little water available again until June when the glaciers provide meltwater again. It is in this crucial window that the ice stupas start melting, offering an invaluable source of water for irrigation early in the growing season, extending the cropp