It's perhaps worth mentioning that metal halide bulbs are an alternative to LEDs that are efficient and produce high quality light. They use an electric arc in

It's perhaps worth mentioning that metal halide bulbs are an alternative to LEDs that are efficient and produce high quality light. They use an electric arc in an inert gas between tungsten electrodes. The old high pressure sodium lights used in street lights and gymnasiums are basically the same technology, but by using a different gas mixture you get a more normal color temperature. They aren't generally used in residential buildings. You could install them, but it tends to be kind of expensive and complicated because they require a ballast. Also, they tend to be most efficient at high wattages, and most people don't want their house lit like the surface of the sun.