Einstein Refrigerator Making a Comeback?
Albert Einstein is probably most remembered by the public for his General Theory of Relativity, but how many remember his 1930 invention of a refrigerator that used no electricity? I wasn’t there when it was introduced, but I knew several people who had one, and they weren’t all that happy with it, primarily because it wasn’t that efficient.
The idea was great, it operated without electricity, using ammonia, butane and water. The principle being that water boils at a much lower temperature at high altitudes where air pressure is lower than it does when you’re at sea level, where air pressure is higher.
Malcom McCulloch, an electrical engineer at Oxford University in the U.K., is leading a team in a three year project to produce appliances that can be used in places without electricity. Or, for that matter, places with electricity, why not?. That’s when McCulloch latched on to Einstein’s fridge idea.
Einstein’s concept, shown in the image above, works thusly. At one side is the evaporator, a flask that contains butane. “If you introduce a new vapor above the butane, the liquid boiling temperature decreases and, as it boils off, it takes energy from the surroundings to do so,’ says McCulloch. ‘That’s what makes it cold.”
