A new way to harness waste heat Vast amounts of excess heat are generated by industrial processes and by electric power plants; researchers around the world have spent decades seeking ways to harness some of this wasted energy. Most such efforts have focused on thermoelectric devices, solid-state materials that can produce electricity from a temperature gradient, but the efficiency of such devices is limited by the availability of materials. Now researchers at Massachusetts Institute of Technology (MIT) and Stanford Univ. have found a new alternative for low-temperature waste-heat conversion into electricity—that is, in cases where temperature differences are less than 100 C. The new approach, based on a phenomenon called the thermogalvanic effect, is described in a paper published in Nature Communications by postdoctoral rese...