Matt Scullin, Power Recycler

When Thomas Edison built the world’s first commercial power plant in Manhattan in 1882, he also sold the exhaust heat from its coal-fired boilers to nearby buildings. Since then, scientists and engineers have sought new technologies that would expand on Edison’s elegant idea of using energy twice. The latest Holy Grail: perfecting thermoelectrics, materials that can convert heat into electricity.

Matt Scullin, 28, is trying to improve the technology which in its current state isn’t very efficient, costs a lot, and is difficult to manufacture on a large scale. The New York City native, who earned his PhD in materials science from the University of California at Berkeley, was part of a group of researchers at Lawrence Berkeley National Laboratory that in 2010 discovered a way to use silicon—which is cheap and easy to handle—as an efficient thermoelectric material. His two-year-old San Francisco startup, Alphabet Energy, has licensed the patent and is working to commercialize silicon-based thermoelectric generators for utilities, manufacturers, and other industries that stand to benefit from reusing heat.