Roland Piquepaille writes "According to two professors at Rensselaer Polytechnic Institute (RPI), light-emitting diodes (LEDs) and smart lighting could save trillions of dollars worldwide in the next ten years. They claim that innovations in photonics and solid state lighting could also lead to 'a massive reduction in the amount of energy required to light homes and businesses around the globe.' Of course, I would be happy to fully agree with the researchers, but these benefits will only be achieved if all of the world's light bulbs are replaced with LEDs. I seriously doubt it can happen. Still, it's certain that a new generation of lighting devices based on LEDs will become available and reduce our carbon dioxide emissions. Read more for additional references and pictures showing the efficiency of various lighting technologies and how white light can be created by using several LEDs"