Waste Heat Recovery
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Japan researchers successfully synthesize new lightweight thermoelectric material
October 25, 2016
Researchers at the Materials Function Control Laboratory at the Toyohashi University of Technology and the Nagoya Institute of Technology have successfully synthesized a new thermoelectric material, CaMgSi, an intermetallic compound. The key to this development was the synthesis procedure; bulk CaMgSi intermetallic compound was synthesized by combining mechanical ball-milling (MM) and pulse current sintering (PCS) processes.
The new thermoelectric material is lightweight, with a low density of 2.2 g/cm3. One of the possible applications of the material is in automobiles to utilize waste heat emitted from engines, the research team suggested. A paper on the work is published in the Journal of Alloys and Compounds.
ARPA-E issues RFI on lower-grade waste heat recovery technologies; focus on solid-state systems
August 19, 2016
The Advanced Research Projects Agency - Energy (ARPA-E) has issued a request for information (DE-FOA-0001607) on lower-grade waste heat recovery technologies. Consistent with the agency’s mission, ARPA-E is seeking clearly disruptive, novel technologies, early in their R&D cycle, and not integration strategies for existing technologies.
In 2015, 59.2 quadrillion BTU of energy was wasted mainly in the form of heat. Much of the waste heat has been characterized by its source and its temperature, particularly in the transportation and power generation sectors. Through aggregated analysis of waste heat data from the literature, ARPA-E found that approximately 85% of work potential from waste heat sources across all sectors in the United States comes from waste heat sources at or below 400 °C. Thus, ARPA-E is keenly interested in waste heat conversion in this temperature range.
Manchester team proposing graphene-based ballistic rectifier for waste heat recovery
June 03, 2016
Researchers at the University of Manchester (UK) have developed a graphene-based nano-rectifier (“ballistic rectifier”) that can convert waste heat to electricity. The nano-rectifier was built by a team led by Professor Aimin Song and Dr. Ernie Hill, in collaboration with a team at Shandong University (China).
The device exploits graphene’s phenomenally high electron mobility—a property which determines how fast an electron can travel in a material and how fast electronic devices can operate. The resulting device is the most sensitive room-temperature rectifier ever made, the researchers said. Conventional devices with similar conversion efficiencies require cryogenically low temperatures.
NEC, NEC TOKIN and Tohoku University develop spin-Seebeck thermoelectric device w/ 10x better conversion efficiency
April 25, 2016
NEC Corporation, NEC TOKIN Corporation and TOHOKU UNIVERSITY have jointly created a thermoelectric (TE) device using the spin Seebeck effect (SSE) with conversion efficiency 10 times higher than a test module that was produced based on a multi-layered SSE technology published by the Tohoku University group in 2015.
The spin-Seebeck effect is a thermoelectric effect discovered in 2008 by Prof. Eiji Saitoh and Associate Prof. Ken-ichi Uchida of Tohoku University (Keio University at that time). This is a phenomenon in which a temperature gradient applied in a magnetic material produces a spin current along the temperature gradient. The spin current is a flow of a magnetic property of an electron.
ORCnext project concludes waste heat recovery efficiency can be boosted by 20-25%
March 18, 2016
The four-year projet ORCNext, aimed at developing knowledge and design tools for next generation of Organic Rankine Cycles (ORCs), has concluded that waste heat recovery efficiency can be increased by 20 to 25% through appropriate cycle selection, efficient expanders, appropriate control and less oversizing of the heat exchangers.
The project, funded by the government agency IWT, ran from February 2012 to January 2016 and was a partnership between Ghent University, University of Antwerp, University of Liège and Atlas Copco.
Fraunhofer characterizes Alphabet Energy thermoelectric PowerCard; up to 5% fuel economy improvement in automotive
January 14, 2016
Alphabet Energy is commercializing low-cost, efficient thermoelectric materials for power generation leveraging technology initially developed at the Lawrence Berkeley National Laboratory. (Earlier post.)
The company has now announced characterization from the Fraunhofer Institute for Physical Measurement Techniques IPM of heat flow and thermal resistance (in air) of the Alphabet Energy PowerCard, the company’s core thermoelectric device for power generation. The PowerCard has shipped to customers in a variety of industries, including automotive; has been tested extensively; and is now entering high-volume production.