(Northwestern University) Northwestern University scientists have developed a thermoelectric material that is the best in the world at converting waste heat to electricity. This is very good news once you realize nearly two-thirds of energy input is lost as waste heat. The material could signify a paradigm shift. With a very environmentally stable material that is expected to convert 15 to 20 percent of waste heat to useful electricity, thermoelectrics now could see more widespread adoption by industry.