This one could just be filed under ‘this is really cool’. Also, I can’t believe it has passed me by my entire life. Have you ever heard of a solar furnace? It’s a James- Bond-esque creation which focusses light from the sun on a massive scale to heat a very small area to a very high temperature. They built on in the Pyreness in 1970, a big one, and it can produce 1000 kW per square centimetre!
A solar furnace is a structure made up of a parabolic mirror, which reflects light on to a focal point. In the case of the furnace at Font-Romeu in the French Pyrenees, several small mirrors catch light from a hillside and focus it onto the main mirror as well, adding to the power of the construction. The heat produced can be used to generate electricity or to perform experiments in high-temperature physics.
The solar furnace at Odeillo, Font-Romeu in the Pyrenees of France (pictured here) was opened in 1970 and is the largest in the world. According to Wikipedia, the rays are focused on to an area the size of a cooking pot and this means that they can reach a temperature of up to 3,000 degrees Celsius.
The first modern solar furnace is is still in place at Mont Louis, near to Odeillo. It was built in the 1940s. The Pyrenees were chosen as the site because the can recieve 300 sunny days a year.
Take a look at the large Odeillo furnace on Google Earth, via this KMZ file.