Today is the second time we meet up with Scottish scientist James Dewar. We’ve already discussed his ingenious Dewar flask, made famous by the Thermos company. As mentioned at the time, Dewar worked with some rather chilly subjects – liquified and frozen gases, to be exact – and he created his insulating flask to serve his practical need for a container that could maintain the low temperatures of the liquified gases he studied.
The reason Dewar pops up on this blog today, is again related to his low temperature work. It was on this day, 9 March 1893, that he informed a meeting of the Royal Society that he had succeeded in freezing air into a clear and transparent solid. As reported in The Manufacturer and Builder Volume 25 Issue 7, he requested additional funding to further study the exact properties of this frozen air; he postulated that “it may be a jelly of solid nitrogen containing liquid oxygen, much as calves’ foot jelly contains water diffused in solid gelatine. Or it may be a true ice of liquid air, in which both oxygen and nitrogen exist in the solid form.” Part of this confusion on the part of Dewar was that he had not been able to freeze pure oxygen, hence it was not clear how the oxygen part of the frozen air behaved.
Interestingly, frozen air has recently resurfaced as an subject of research interest. As reported last year on various sites such as ecogeek, sustainable business.com and NBC News, a UK-based company Highview Power Storage has developed a proprietary process using cryogenic air (actually nitrogen, liquified at -321 degrees Fahrenheit) as a way to store energy. Available energy is used to freeze/liquify the nitrogen, which is then kept in its frozen form in a highly isolated, giant vacuum flask. When energy is required, the nitrogen is allowed to warm to ambient temperature, and the energy released during its transition to a gas phase, is harvested to drive a turbine that generates electricity.
While the technology is not yet able to achieve the efficiency of current battery technologies, it is a potentially less environmentally harmful, greener approach.
Now there’s a reason to raise a glass of very chilled liquid to James Dewar and his frozen air!