@stshank@mstdn.social From the article, passive cooling prevents the roof from getting too hot, and insures that the air inside the house is not hotter than the ambient outside temperature. That's cool. But I think this fails if the air outside is hotter than 37C. If I remember thermodynamics correctly, you can only cool the inside lower than the outside with some kind of heat pump, and that requires spending energy. Maybe solar panels on that roof?