AC units for a large (or glassy) room in a hot arid climate use about 1 ton of cooling - equal to melting 1 ton of ice. A typical AC machine has COP ~3.5 so uses ~1 kW of electricity to do that. A typical engineering improvement would improve COP to 4-8 for efficiency, and a typical architectural solution would be to remove the air conditioner and allow natural ventilation. Incremental progress fails to really address the scale of the problem with 50 million units/year being installed, and climate variability makes the architectural solution unreliable. Our comfort system will use <0.1 kW of electricity, have >10x less CO2, and easily be powered by PV. In addition, the materials used are lightweight and low carbon, plus no walls/glass/insulation are needed.