Lightweight Thermal Energy Recovery (LighTER) System
General Motors R&D received a $2.7 million federal award Monday that will help build a prototype using Shape Memory Alloy, or SMA, that would generate electricity from the heat in automotive exhaust.
“When you heat up a stretched SMA wire, it shrinks back to its pre-stretched length, and when it cools back down it becomes less stiff and can revert to the original shape” said Jan Aase, director of GM’s Vehicle Development Research Laboratory. “A loop of this wire could be used to drive an electric generator to charge a battery.”
It is too soon to identify a vehicle where this technology could work, but hybrid or conventionally powered vehicles are possible applications.
Advanced Semiconductor Materials for High Efficiency Thermoelectric Devices
Phononic Devices, Inc. (Cary, NC) in partnership with the University of Oklahoma, the University of California Santa Cruz, and the California Institute of Technology, will develop a completely new class of high efficiency thermoelectric devices and materials that combine enhanced Seebeck thermopower with thermally insulating semiconductor materials to increase solid state thermal-to-electric conversion efficiencies to unprecedented levels. With greater than 60% of all U.S. energy lost in the form of waste heat from power plants, industrial processes, and vehicles, this high efficiency new thermoelectrics technology holds great promise to enable the U.S. to tap into this vast hidden energy resource to drastically reduce U.S. greenhouse gas emissions.
Phononic Devices’ approach combines proprietary design concepts, nanostructured materials, and a thin-film semiconductor platform to dramatically improve heat-to-electricity conversion efficiency. The company’s breakthrough will enable Thermoelectric Generators (TEG) that harvest waste heat for power generation; it can also be applied in reverse, enabling Thermoelectric Coolers (TEC) that can pump heat out of a system for cooling. Phononic Devices’ technology stands to unlock the latent $125 billion market for thermoelectric energy harvesting, cooling, and refrigeration, enabling mass manufacturing and customer adoption at price points undercutting incumbent technologies
Harvesting Low Quality Heat Using Economically Printed Flexible Nanostructured Stacked Thermoelectric Junctions
The University of Illinois at Urbana Champaign (Urbana, IL), in collaboration with MC10, Inc., will develop an economic and highly scalable non-lithographic approach to fabricate large area arrays of 1-D concentric silicon nanotubes for low cost thermoelectric devices. This low cost, earth abundant, flexible new thermoelectric technology holds great promise to allow the U.S. to begin to harvest the more than 60% of its energy that it loses in the form of waste heat, providing an opportunity to drastically reduce U.S. energy waste and greenhouse gas emissions.
Professor Sinha’s grant will fund the development of a novel thermoelectric waste heat harvesting device based on large area arrays of 1-D concentric silicon nanotubes which can be inexpensively printed as stacked thermoelectric junctions. This thermoelectric technology holds promise for providing low cost harvesting of energy now lost in the form of waste heat in settings ranging from electricity generation to automobiles to massive data centers. Low quality waste heat constitutes a 2 TW untapped source of energy in the US but is technically challenging to harvest as useful energy. High coefficient of performance thermoelectric conversion such as what the team seeks to achieve, can potentially harness approximately 4-5% of this waste heat and add 23% to the current US electricity production at zero additional carbon or noise emission.