Scalable Nanostructured Thermoelectric Generation System for Industrial Waste Heat Recovery

Every year, an estimated 7 quadrillion British thermal units ¿ about 15% of the total energy consumed in the United States ¿ is lost in liquid and gaseous waste streams from industry. Energy from low- to medium-grade waste heat (50-250oCelsius) cannot be efficiently recovered by conventional heat exchanger technologies, because of its distributed nature and insufficient temperature difference. Meanwhile thermoelectric generation technologies are not yet economically viable. This project will implement a new advanced thermoelectric generation technology based on flexible large-area tiles fabricated from nanoengineered thermoelectric materials. Cascading these tiles will result in a thermoelectric waste heat recovery system with heat-to-electricity conversion efficiencies that are three times better than that of current technology. In Phase I, material samples were fabricated and tested. The results demonstrated an enhancement in the thermoelectric conversion efficiency of the nanoengineered materials. Analysis of the results indicated that electricity can be produced at 30 cents per Watt, making it a viable alternative energy technology. Phase II will optimize the design of the advanced thermoelectric generation system, mature the fabrication process for the nanoengineered thermoelectric materials, and complete the development of a fully functional prototype for waste heat recovery applications. Commercial Applications and Other Benefits as described by the awardee: Improved waste heat recovery systems can potentially recover1.8 quadrillion British thermal units of energy, a major DOE goal. In addition to industrial uses, the system could provide remote, highly reliable, low-power sources for pipeline and telecommunication infrastructure monitoring. Another major application lies in the auto industry, where fuel-efficient and hybrid automobiles would benefit from the recovery of vehicular coolant/exhaust heat.