The Einstein-Szilard refrigerator: (A patent benchmark)

This is the story of an invention made by two famous scientists – Albert Einstein and Leo Szilard – who dramatically changed the world we live in.

Einstein, of course, is well known for his Theory of Relativity and the famous equation E= mc² .

Szilard, among his many accomplishments, was co-inventor and patentee of the first nuclear reactor.  (More about that in a future blog.)  Their joint activities in the early 1940’s strongly influenced the development of nuclear energy and creation of the atomic bomb.

These two world-renowned scientists seem to be an unlikely combination to become co-inventors of a common household appliance.  But in the late 1920’s, newly developed electric refrigerators began to replace traditional iceboxes in households in the developed nations.

With the new technology came unexpected hazards.  The refrigerators occasionally leaked toxic gases that could be hazardous or even fatal.   Einstein and Szilard read a newspaper story about a family that died when a broken seal in their refrigerator leaked toxic fumes into their house.  It is believed that knowledge of the tragedy inspired the two scientists to invent a safer refrigerator.

The device they invented was simple, energy efficient, and safer.  It had no moving parts and thus was less likely to develop leaks.  And it did not require electricity.  The inventors filed a patent application on their refrigerator on December 16, 1927 and were granted U.S. Patent No. 1,781,541(PDF) on Nov. 11, 1930.

Despite the advantages of their patented refrigerator it did not become a major success in the consumer market for various reasons, not the least of which was the depression of the 1930’s.  However, the licensing of some of their patented technology provided them with income for their further important research in the realm of physics.

This could be the end of the story: but it isn’t.  New technology often brings with it unanticipated results that may not be recognized for years.  Such results are often negative, but not in this case.

The patent on the Einstein-Szilard refrigerator was published more than 80 years ago, and for most of the time since then, was little known to the general public and even to many physicists.  However, in recent years, it has become the subject of renewed interest to researchers in England and in the United States.

The interest has been spurred by the recognition that modifications of the refrigerator can result in models that are more energy efficient, and do not require electricity.  They can even be powered by solar energy and thus could be used in underdeveloped areas where electricity is not always available.  Moreover, this refrigerator can eliminate the need for using chlorofluorocarbons (CFCs) as the refrigerant. (More about the invention and hazards of CFCs in a future patent blog.)

Maybe after 80 years the world is ready for the Einstein-Szilard refrigerator!