Mark Megahan
A team of Colorado engineers found a way to harvest excess heat from industrial processes and turn it into electricity. The breakthrough is that they get enough back to be useful. That seems to violate a basic law of physics but it doesn’t.
Capturing wasted heat
Engineers and material scientists from the Paul M. Rady Department of Mechanical Engineering at CU Boulder found a really efficient way to harvest heat.
Their new technology to turn thermal radiation into electricity works so well it appears to break a “basic law of thermal physics.”
Assistant Professor Longji Cui heads up the Cui Research Group. They’ve been working “in collaboration with researchers from the National Renewable Energy Laboratory and the University of Wisconsin-Madison.”
Their successful approach to harvest waste heat was recently featured in the journal Energy & Environmental Sciences.
The group’s approach “has the potential to revolutionize manufacturing industries by increasing power generation without the need for high temperature heat sources or expensive materials.”
That means they can store clean energy and lower carbon emissions.
Harvest from anything
The equipment is small and affordable enough to gain useful amounts of power from heat generated by a wide variety of sources.
Not only can they pull electricity from “geothermal, nuclear and solar radiation plants,” they can get it from steel mills and concrete plants. Normally, massive amounts of energy are wasted into thin air.
“Two-thirds of all energy that we use is turned into heat,” professor Cui notes.
“Think of energy storage and electricity generation that doesn’t involve fossil fuels. We can recover some of this wasted thermal energy and use it to make clean electricity.” There are a whole bunch of high-temperature industrial processes.
Thermophotovoltaics can harvest heat to generate electricity. Their efficiency is limited by Planck’s thermal radiation law. It only applies when there’s a vacuum gap involved.
Cui’s device replaces it with a patented layer of glass. Their “zero-vacuum gap” solution “allows thermal heat waves to travel through the device without losing strength, drastically improving power generation.” It’s also cheap.
