Mont-Louis (Catalan: Montlluís or el Vilar d'Ovansa) is a commune in the Pyrénées-Orientales department in southern France.
In 2008, the citadel and the city walls of Mont-Louis were listed as a UNESCO World Heritage Sites, as part of the "Fortifications of Vauban" group.
The Mont-Louis Solar Furnace, is the world's first solar furnace, built in 1949, by engineer Felix Trombe. It is open to visit for practical education on solar energy uses and technologies.
The Mont-Louis Solar Furnace is an experimental solar furnace - a solar thermal energy facility that was built in 1949. It was the first facility of its kind in the world, and was a precursor of the Odeillo Solar Furnace. It provides a thermal power of 50 kW.
A solar furnace is a structure that uses concentrated solar power to produce high temperatures, usually for industry. Parabolic mirrors or heliostats concentrate light (Insolation) onto a focal point. The temperature at the focal point may reach 3,500 °C (6,330 °F), and this heat can be used to generate electricity, melt steel, make hydrogen fuel or nanomaterials.
The largest solar furnace is at Odeillo in the Pyrénées-Orientales in France, opened in 1970. It employs an array of plane mirrors to gather sunlight, reflecting it onto a larger curved mirror.