But wouldn’t a light bulb (the old, illegal, incandescent kind) under a flower pot do the same thing and be less of a fire hazard?
Yes, the key is the “mass” of the clay absorbing and re-radiating the heat as infrared to the nearby body to be warmed.
Same principle as the rocket mass heater.
Yes I would say it would. I now some people with hunting dogs that heat the dog house with a incandescent bulb. But I believe the idea here is something that would work even with the power off.
“But wouldn’t a light bulb (the old, illegal, incandescent kind) under a flower pot do the same thing and be less of a fire hazard?”
If your power worked, plug in a heater. We are talking about power being off and a way to have heating.
***But wouldn’t a light bulb (the old, illegal, incandescent kind)****
Don’t you mean a 100W HEATING bulb to keep baby chicks warm and water pumps from freezing, but is a violation of Federal Law to be used as a light source? ;-D