This intense heat can be used in industrial applications, like boiling water to sterilize soup cans or to produce electricity. Solar concentrators come in three main designs, parabolic troughs, parabolic dishes and central receivers. The most common is parabolic troughs, long curved mirrors that concentrate sunlight on a liquid inside a tube that runs parallel to the mirror. The liquid, at about 300 degrees C, runs to a central collector, where it produces steam that drives an electric turbine. Parabolic dish concentrators are similar to trough concentrators, but focus the sunlight on a single point.
Dishes can produce much higher temperatures, and so can produce electricity more efficiently.
But because they are more complicated, they have not succeeded outside of demonstration projects. In an internal combustion engine, like in a car, heat is produced by gasoline exploding inside the engine, causing air to expand and push the pistons. In a stirling engine, the heat source is on the outside. To be accurate, there is no combustion with a solar-powered stirling engine, since the heat is supplied by mirrors reflecting sunlight. These dish-stirling generators produce about 30 kilowatts of power, and can be used to replace diesel generators in remote locations.