A Lot Of Heat Is Wasted, So Why Not Convert It Into Power?
What if there were a way to take the waste heat that spews from car tailpipes or power plant chimneys and turn it into electricity? Matt Scullin thinks there is, and he's formed a company to turn that idea into a reality.
The key to Scullin's plans is something called thermoelectrics. "A thermoelectric is a material that turns heat into electricity," he says.
Never heard of thermoelectrics? Don't feel bad. They tend to have rather esoteric uses. For example, NASA uses them to turn heat into electricity to power spacecraft.
But NASA is using older technology. Scullin says there's a new class of thermoelectrics developed at Michigan State University made from a compound called tetrahedrite that can do a better job for less money.
One factor working in Scullin's favor: There's plenty of waste heat out there to be harvested. "We waste heat because of the laws of thermodynamics," he says.
Those laws state that it's impossible to use the energy in fuel to power a car or generate electricity without some of that energy going to waste.
Thermoelectrics haven't attracted much attention in the alternative-energy world, but Scullin seems to be drawn to areas others have overlooked. That was on display his very first days as an engineering undergraduate at the University of Pennsylvania.
"At orientation, there was a table set up for every major in the engineering school," he says. "And computer science had 30 kids crowded around the table and one professor. Mechanical engineering was similar. And then the material science table had no students at it, and two professors. So I said I'd better go there, and figure out what's going on."
Scullin liked developing new materials, so when he finished up at Penn he headed out to UC Berkeley for a graduate degree.
At Berkeley he began to get interested in the world of alternative energy. And then he realized that developing new thermoelectric devices was a way to merge his expertise in materials with his interest in energy.
Rather than pursue this in an academic setting, Scullin wanted to have a more tangible impact, so he decided to start a business, although his business training was rather idiosyncratic.
"The way that I learned about startups in kind of a real intense way is when a buddy from Penn called me up and said, 'Hey Matt, I'm going to start an online gambling company, and I'm going to come out to the Bay Area to do this. Can I crash on your couch for a couple weeks?' And you know I lived in a studio in Berkeley as a grad student. And I said, 'Hey yeah, you can have the couch for a couple weeks. Sounds fun.' "
So the friend showed up.
"Six months later he was still on my couch, and I had been there with him as he hired a team, and found his first investors, and figured out how to get this company started. So I thought well, if he could do it, I could do it, and why not?"
After we donned protective eyewear, Scullin took me on a tour of the company workspace.
"We've got a combination of lab and manufacturing back here. And this thing that you're looking at is the largest thermoelectric test system that I believe exists in the world," he says.
Scullin picks up what looks like a small printed circuit card. It has a thermoelectric imbedded in it. He calls it the PowerCard.
"The cool thing about this PowerCard is that it's like a cell," he says. "You can almost think of it like how a solar cell is with the sun. You can put one out in the sun, and get a small amount of power, or you could put a square mile of solar cells out in the sun, and you've got a power plant."
Scullin says it's the same with these thermoelectric PowerCards. If you've got a large waste heat source, like the exhaust stack of a coal-burning power plant, then you string together a lot of PowerCards. But if you don't have much heat, you only use a few of them.
"Eventually, we'd like to have thermoelectrics on the human body, and in buildings and in all sorts of other locations," Scullin says.
He acknowledges right now, thermoelectrics are a tiny part of the electricity generating market. And Scullin knows he's facing a lot of hurdles to get people to try his new technology.
"I stay excited because I get to geek out about these things that I really love. And at the same time, I get to build something. And that's really what I want to be doing. I want to be making something," Scullin says.
He says that's more important than making a fortune.
"Don't get me wrong. We'd love to make tons of money here at Alphabet Energy. That's what we're going for. But this is a long-term project. This is something that we think we have to work on for a long time to make it a success."
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