Our refrigerators are increasingly more energy efficient, but they contain refrigerant gases that can potentially be pollutants. An idea from the past could now give us a truly green fridge.
A green fridge that uses no electricity and contains no harmful gases? It sounds like
a modern-day innovation but it was actually invented by Einstein and his student Leó Szilárd back in 1926. In those days fridges used a highly toxic gas, and wear and tear on the internal mechanism frequently caused the seals to break and harmful fumes to leak out. To get around this problem the man who developed the theory of relativity invented a fridge without a motor based on the principle of absorption, which did not involve the
use of harmful pollutants.
Unfortunately freon became commonly used in the current refrigeration systems and so this prototype was never commercially produced. The man who recovered the patent and brought the newly-named Einstein Refrigerator back to the world is Malcolm McCulloch, an electrica engineer at Oxford. The British team started work on a three-year project to develop
a fridge powered by renewable sources of energy, such as small photovoltaic panels, that works with more environmentally-friendly liquid gases.
Another group working on a zero-emission fridge is Camfridge, a start-up at Cambridge
University that chose to use magnetic fields. Magnetic refrigeration is based on the magnetocaloric effect obtained with very expensive and hard-tofind alloys, such as lanthanum and silicon-germanium.
The Camfridge doesn’t have a motor so it will be very spacious and quiet. The scientists are developing less costly alloys to produce this innovative green fridge on a large commercial scale.
Freeijis, the electricity-free fridge
A combination of technology and design provides the winning characteristics of Freeijis, the electricity-free fridge designed by Caterina Falleni, a young designer who graduated from the ISIA Design Institute in Florence, and won the prestigious Alexera Singularity Contest which enabled her to study at the NASA centre in Silicon Valley. Freeijis is a domestic cooling system for fruit and vegetables, and the way it works is as simple as it is innovative: it is based on the same water evaporation process used by the human body to regulate body temperature. Caterina is now working on a new version of the first prototype; an aluminium container inside another clay container with water in between the two that enables evaporation and the internal part to automatically cool. This device has great social as well as environmental value because it makes the consumer more responsible and is based on the concept of clean, natural energy that can be used by everyone.