The Einstein refrigerator is an Albert Einstein invention that uses green technology.
It was co-invented with Leo Szilard who was one of his physics students at Zurich University. The invention was patented in 1930 and licensed to various companies including Electrolux
Refrigeration was introduced in 1834, however there were concerns of poisoning because faulty seals in the mechanical compressors would leak toxic gases such as methyl chloride and sulfur dioxide.
A family in Germany died from such an event and it is believed that this tragedy motivated Einstein to design a non-toxic fridge.
The Einstein refrigerator uses an absorption process where changes in pressure between liquids and gases (pressurized ammonia, butane and water) drops the temperature in a food compartment.
Einstein also designed an electromagnetic pump that required no moving parts instead of a mechanical compressor thus eliminating seal leaks.
Einstein was very familiar with patents and licensing.
When Einstein graduated from the Swiss Federal Institute of Technology he couldn't find work as a teacher.
Through a fellow student, he got a job as an assistant patent examiner with the Swiss Patent Office. He reviewed patent applications for electromagnetic inventions.
Einstein later became an associate professor at the University of Zurich and then a professor at the Charles University of Prague.
This Albert Einstein invention was the only invention patented by Einstein who became more famous for his theories on physics rather than for his work in refrigeration, although scientists are now investigating this technology.
Scientists at Oxford University have reconstructed Albert Einstein's invention in the hopes of developing an eco-friendly refrigerator that operates without electricity or moving parts.
Modern refrigeration uses compressed gases that are harmful to the environment.
The need for eco-friendly cooling technology is becoming more important given the demand by developing countries for air conditioning and refrigeration.
Replacing current technologies with energy efficient, green technology is why scientists are now resurrecting Einstein's invention.
Time Magazine published the Top 50 Best Inventions of 2008 and the Einstein refrigerator was listed as the 31st best invention.
Although invented over 78 years ago, it is an example of how the rediscovery and exposure of past technologies are becoming more relevant.