Nothing new under the sun – part iiPosted: Friday, 11th November, 2011
Previously on this blog I posted images of concentrating solar thermal (CST) devices from Nature in the 1880s. They showed that CST technology – some of it looking strikingly similar to modern systems – was described in scientific literature far earlier than we tend to realise.
Below, however, are images of an even earlier example. Antoine Lavoisier, the father of modern chemistry, carried out experiments in 1772 with a solar furnace that went by the impressive name of the ‘great burning-lens of Tschirnhausen’. Disappointed by the narrow focus of this device, he and his colleagues were able to arrange for the use of a new solar instrument they called a ‘liquor lens’, which used alcohol-filled glass lenses to concentrate light. (The glass was donated by Saint-Gobain, a company that amazingly is not only still in existence today, but is still supplying glass mirrors to the solar thermal industry.) The scientists used it to investigate the role of air in the combustion of many different substances, and Lavoisier also used it to show that diamond is made only of carbon.
All this took place in Paris near the Louvre, where, according to some accounts, ‘elegant women and the curious came to stroll there and observed the scene with amazement’.
After Lavoisier, solar furnaces seem to have been completely ignored until the early 1900s. Nowadays, modern solar furnaces use mirrors to focus the sun instead of lenses, and are much more powerful than Lavoisier’s. However, they use the same general principles and are still very valuable research tools for scientists.