Corey Shemelya (EG '10) and Dante DeMeo (E '08, EG '11), both fifth?year Tufts engineering Ph.D students, won the $10,000 grand prize in the Dow Sustainability Innovation Student Challenge Awards this year for their five?year research project titled "Harvesting Heat - Changing Waste Heat into Usable Electricity."
Shemelya and DeMeo's research focuses on thermophotovoltaic (TPV) devices that capture heat and turn it into electricity. TPV cells differ from traditional photovoltaic cells, or solar cells, in that they can capture and convert infrared energy or heat into electricity, allowing for more practical uses of the technology.
They conducted their research in the Tufts School of Engineering's Renewable Energy and Applied Photonics (REAP) Laboratories. As research into thermovoltaic energy harvesting had not been conducted at Tufts before, challenges included not only funding but also consolidating research capabilities, collaborating with external researchers and finding relevant resources at Tufts, according to Shemelya.
In their project abstract, Shemelya and DeMeo propose developing a long?wavelength TPV energy harvester to convert radiated heat into electricity.
The device would be able to create usable energy from a variety of waste heat sources.
"The idea of this technology, thermophotovoltaics, can be used for a lot more applications than the traditional photovoltaic type energy harvester, which usually only captures visible radiation, like what you see on your roof, a solar panel," DeMeo said.
"Our technology can do infrared radiation as well as visible and opens up a whole new range of applications."
According to Thomas Vandervelde, assistant professor in the Department of Electrical and Computer Engineering and REAP Labs director, TPVs first appeared in the 1960s. However, technological limitations at the time meant that TPVs were unable to reach a commercial market.
Shemelya and DeMeo's current research has made use of advancements in technological materials that allow an expansion in the reach and utilization of TPVs.
"We applied some new material technology that [was] developed through the field of infrared filter detectors, infrared cameras," Vandervelde said. "We've applied that new technology now to the idea of TPVs, to create devices that are actually functional, usable in a marketable setting."
Vandervelde said the current research looks at the diagram of harvesting waste heat from processes such as glass and steel making. As the processes release heat into the environment, TPVs allow factories to capture some of the lost energy and recycle it into other factory processes, such as powering lights or heaters, according to Vandervelde.
Shemelya and DeMeo will focus their future research on further decreasing the temperature of source heat and generalizing the technology used.
"By harvesting the waste heat, you basically can improve the efficiency of any device, whether it's an industry process, your iPhone, blender, dish?washer, home heater," Vandervelde said. "We can improve the efficiency of the energy cost of running it."
TPVs have the potential to act as a sort of buffer when switching from a non?renewable to a renewable energy source.
As they do not require completely new energy bases, TPV technology can be applied to current energy sources to increase energy efficiency, according to Shemelya.
"By ... implementing [TPV technology] in current energy sources, you are allowing [a] decrease [in] the amount of waste sources that are needed to produce the same amount of power," Shemelya said.
"So we are in a unique position where we were trying to create a technology that can act as a buffer while we are trying to move towards completely renewable energy."
