Solar Cooling in cities
Ever trudged in baking sun down the concrete corridors of a modern city and wondered how it got quite that appallingly hot?
It is an effect called a heat island. If you put air conditioning in a building it pumps heat out of the building into the surrounding air. The power it takes to pump out all of that heat is also turned into heat. A whole city full of buildings heating the city with their air conditioning means a much hotter city so even more power is needed to keep the buildings cool!
Solar cooling shades the building and sucks up heat to produce cooling. It still rejects some heat into the air but only the heat that would have come from the sun anyway so it doesn’t heat the city. It can even store the heat by warming water for washing and bathing, locking it away at the height of the day.