Andrew Ponec. [Image: Courtesy of Antora Energy]
The July/August 2023 issue of Optics & Photonics News featured the magazine’s biennial feature spotlighting 10 Entrepreneurs to Watch. Here, we offer an interview with one of those entrepreneurs, Andrew Ponec, the founder and CEO of US-based Antora Energy. Antora is pioneering a system that stores energy from cheap, clean solar- and wind energy in large, heated carbon blocks adjacent to industrial facilities—and then repurposes that stored heat energy as industrial heat and thermophotovoltaic electricity.
Can you tell me, in a few sentences, what Antora Energy is about—what the company does, where you want to take it, why it’s important?
Andrew Ponec: At the core, we’re a company working to help stop climate change. And we’re doing that by electrifying heavy industries.
What we’re doing is solving the fundamental mismatch between solar and wind resources, which are now very cheap and clean but are only available some of the time, and industrial processes that typically require heat energy and electricity 24/7 and can’t tolerate interruptions. We’re the thing in between that new opportunity of solar and wind and the existing industry, that can allow industry to decarbonize.
The heat angle seems particularly interesting. I don’t think people think about heat as a tradable commodity in the same way they do for electricity.
Heat is such an interesting area. And I think it’s one that has been overlooked. It’s getting more interest now, but I’d say a lot of people have not been thinking about it.
We use a lot of electricity in our daily lives; we’re very familiar with it in residential and commercial settings. Process heat, the kind of heat used in industry, it’s pretty out of sight, out of mind. But if you look at it, it’s a huge portion of global emissions. About 30% of all global emissions are industrial emissions; it’s the single largest sector. And within industry, you actually use about twice as much heat energy as you do electrical energy. So it’s an enormous, enormous problem that has to be solved if we’re going to fully decarbonize.
If I’m understanding correctly, Antora is using renewable energy to heat up large carbon blocks, and then redistributing that stored heat when it’s needed—either to provide electricity through thermophotovoltaic cells, or sending process heat directly to the facility. Also, you’re sending this energy into the facility as light, which is kind of fascinating. Could you talk a bit more about that?
Absolutely. The use of light is a super-interesting part of this.
As a lot of your readers probably know, thermal radiation has a temperature-to-the-fourth dependency relationship. That means if you double the absolute temperature, you get 16 times as much thermal radiation. So when we’re dealing with low temperatures—the kind of stuff we deal with in our everyday lives—light is not an important mechanism for heat transfer. Instead, conduction, where you have heat traveling through a solid material, or convection, when you’re kind of flowing some gas—those end up being how heat is moved around.
“The use of light is a super-interesting part of this.”—Andrew Ponec
But, counterintuitively, when you get above 1000 °C, you’re absolutely dominated by light as the way that heat moves around. And that gives us a lot of different advantages. One is that by moving thermal energy around as light, we don’t have a lot of the complexity that comes with systems that would move that heat around with a molten metal or molten salt or other mechanisms people have looked at.
Another advantage is, it makes the system very flexible in its output. The light that is coming off of a glowing object, like a block of carbon at above 1000 °C, is incredibly bright—hundreds of times as bright as sunlight. That allows you to generate temperatures that are very high. If you have something at 1500 °C that’s glowing, and you want to heat up something next to it to 1000 °C, you actually get very, very efficient heat transfer between those things.
This is also where the thermophotovoltaics come in. You have this very, very concentrated light, and rather than trying to convert that light into heat by absorbing it on something and then running a conventional heat engine, you can just take those photons directly and convert them into electricity.
How does that heat transfer as light actually work?
It’s just heat traveling through void space. We’re just letting it radiate, through channels, and if some of the radiation is going in the wrong direction, it will get absorbed by something that’s blocking the path, and then re-radiate.
Let’s talk about your background. It seems like renewable energy has been a real theme for you from a research point of view. When, and why, did you start looking at this?
Well, I’ve always loved science. But my interest in climate and renewable energy started in about middle school, when I started reading about climate change. And it was definitely one of those kind of lightbulb moments where it’s like, “I can’t believe that we’re not all talking about this!”
“My interest in climate and renewable energy started in about middle school, when I started reading about climate change. And it was definitely one of those kind of lightbulb moments where it’s like, ‘I can’t believe that we’re not all talking about this!’”—Andrew Ponec
That really set me on this track, where I knew that’s what I wanted to work on. I just wasn’t sure how. I had no concept of engineering or entrepreneurship. But I spent a lot of time in middle school, in high school, learning about these technologies, even making small prototypes of solar panels, wind turbines, things like that.
And then at Stanford, I guess that got more focused into specific areas of chemistry and physics that were related to solar.
I started working in labs that were focused on making new solar photovoltaic materials … and on power conversion technologies that take that solar electricity and put it on the grid, or optimize solar performance. That’s really where my first company, Dragonfly Systems, came from.
Yes, let’s talk about that experience at Dragonfly—you cofounded that, I think, in March 2013 and it was bought by SunPower only a year and change after that. That’s a pretty quick sale.
Yes, it was an incredible kind of whirlwind adventure. It was a year of working through to a prototype and then to a demonstration system. And we got acquired as soon as that demonstration went online.
And then I spent a couple of years at SunPower, first getting from that prototype into a real product, and then actually manufacturing and installing that product in the field. So within about four years, doing every step of the technology development cycle was incredibly fun.
So that’s another entrepreneurial story in your past—is starting a business something you always had an interest in?
It actually wasn’t at all. I never would have thought I was somebody who would be starting businesses; I really thought, Oh, I’ll just be a scientist; I’ll probably be in the lab, just working on the technologies that can improve things.
What really changed was seeing that, in a lot of cases, just creating the technology isn’t enough. You often have to be the one to actually go and push it out into the world. And that’s what happened with Dragonfly. It wasn’t, “Hey, let’s start a business. What’s a good idea?” It was, “Hey, here’s an idea that may be helpful, but the only way to actually make this help anyone is to go start a business to commercialize it.”
That’s a nice lead-in to Antora. Maybe you could take me a little bit through the story of how that got started. In reading about the company, I’ve been particularly struck by the fact that you took the problem first, and then kind of iterated until you found the solution. It wasn’t driven from the ground up by something you had already been working on.
Yes. I think this is such an important part of our story.
You know, there are great technologies that have come from the other direction. There’s a conventional mindset that someone discovers something in the lab, hands it off, and then people go do things with it. But I’ve seen that a lot more of the really impactful technologies have started the other way around, where people have said, here’s a problem, it has to be solved one way or another. Let’s go figure out what technologies—from a very technology-agnostic perspective—might help us solve the problem.
And that’s certainly how we came at the problem at Antora. My cofounders and I didn’t say, “Hey, I worked on thermal energy storage in my Ph.D.; the next step is to do a startup about thermal energy storage.” It was, “How do we convert this new tool that we have—cheap wind and solar, which is variable—into decarbonization impact, broadly defined?”
And so you kind of tested out a number of ideas toward that goal?
Absolutely. Even before we looked at energy storage, we looked at a lot of different climate-related technologies. We narrowed it down to energy storage being really important. And then we looked at flow batteries, hydrogen, compressed air, gravitational energy storage—all of these other alternatives—and came to thermal energy storage after looking at all of those and deciding, Hey, there is something really promising here.
And one of the reasons was because, as we talked about earlier, not only can thermal energy storage do something really important for electricity—because you can convert it to electricity with technologies like thermophotovoltaics—but it can also do something very important for industrial heat, which is an equal if not larger problem in industrial decarbonization.
You mentioned your team, your cofounders—how did that team come together?
My cofounder Justin Briggs and I met while we were at Stanford. He was finishing his Ph.D. program while I was finishing my undergrad, after I had come back from the Dragonfly/SunPower experience. And we started working in this very open way, talking about looking at lots of different technologies.
“Not only can thermal energy storage do something really important for electricity—because you can convert it to electricity with technologies like thermophotovoltaics—but it can also do something very important for industrial heat, which is an equal if not larger problem in industrial decarbonization.”—Andrew Ponec
We kind of came to this idea that thermal energy storage was going to be very useful. And what’s interesting is that all of this time, separately, our third cofounder, David Bierman, had started his own company doing something almost identical to what we were proposing—to the point that one of our advisors, Brian Bartholomeusz, from the Stanford TomKat Center [for Sustainable Energy], watched a talk that David had given and thought for sure that David must be working with us.
So he put us in touch, and we immediately hit it off. There was definitely a moment where we could have been competitors. But we decided that we liked working together and that we have the same sort of view on the ethics and kind of culture we wanted to build in the company. And also, these are just really big problems, so we might as well be working on them together.
Talk a little bit about how the company got initially funded and started up.
Well, one thing I want to say is that we’re just incredibly grateful to the large number of people and programs that helped us get off the ground. I think this is a part of the innovation ecosystem that sometimes gets overlooked.
There were programs like the TomKat Center that I mentioned at Stanford; the Activate fellowship program. These were types of organizations that were willing to take bets on new or less experienced entrepreneurs, and on new ideas at the early stages, when a lot of larger, more mainstream investors would have said, “I’ll wait until you have something more to show.” But there’s always a chicken-and-egg problem: How am I going to show something more if I don’t have any support at the early stages? So we were very much helped by those sorts of programs.
How did you leverage that early support?
We actually spent the first year or two in a pretty small, embryonic stage where we did a lot of work on the techno-economics of these solutions. We were a small team—four, six, seven people at that time. We weren’t doing a ton of experimental work; we were mostly doing the modeling, from the physics perspective, on TPV and thermal energy storage, and asking, Even if things went as well we could hope, is it actually going to matter? Because you can easily burn a few years of your life doing something where you don’t have the right target in mind, and then finding, at the end, that it wasn’t the right thing to be going after.
The system Antora Energy is building uses clean but only intermittently available solar and wind energy to heat large carbon blocks, which serve as stores of heat and thermophotovoltaic energy for heavy industry. [Image: Antora Energy]
It’s only after we were pretty confident of those things that we started taking more traditional venture investment, started a lot of the much more expensive technology development efforts that put us on the trajectory we’re now on.
And where has that trajectory put you at this point?
Well, it’s a very exciting time for all of us. Right as we speak, we’re commissioning our first pilot unit at an industrial site in Fresno County, CA. This is about a 5-megawatt-hour pilot unit. It’s a big steel box full of glowing hot carbon, between a half shipping container and a full shipping container in size.
We are so excited to turn that unit on, and very grateful to the partner that’s giving us hosting the unit. It’s always hard to find somebody who’s willing to say, “I’ll do the first one.” They were willing to do that.
So that’s going to be your demonstration to the world that this can do what you think it will do.
Exactly. It is the first commercial-scale demonstration of taking carbon to these temperatures and extracting useful thermal energy from it in the form of light.
Going back to your experience building the company. You said that you would not really previously have thought of yourself as a person who would build companies. If you were talking to somebody who was starting out in entrepreneurship, what are the lessons you’ve learned from the experience that you might pass on?
I’ve learned so much, and I’m continuing to learn so much, going through this both at Dragonfly and Antora.
The first lesson I really learned strongly at Dragonfly was about where the value of a company comes from. I had what is maybe a more conventional view—that the value of a company has to do with the idea, and the intellectual property, and what the invention is. And that was kind of quickly washed away, when we realized, as a company, partway through the time at Dragonfly, that our initial idea wasn’t actually that great—it was solving the wrong problem for the customer.
And for the most part, we had to kind of rip up the design and start from scratch. All of the inventions and patents and patent licenses we had from Stanford kind of didn’t matter. And there was a crisis of, “Hey, do we even have anything anymore?” You know, if everything we thought was valuable about the company turned out not to be, what were we even doing there?
“I learned that the value was that we had built an incredible team that liked working and learning together, and that we all cared about the same mission ... That was where the core value of the company was.”—Andrew Ponec
And what I learned then was that the value was that we had built an incredible team that liked working and learning together, and that we all cared about the same mission—we wanted to solve this problem. That was where the core value of the company was. And as soon as we realized that problem with our first product, and then transitioned, we very quickly developed the new product, which is the one that we demonstrated and led to us getting acquired.
What else stands out as a lesson learned?
Another thing that I learned was the value of openness. A lot first-time entrepreneurs, myself included, come at it with a fear like, “What if we tell our idea to someone and they steal it?” This took up so much mindspace, and really prevented us in certain cases from being open about what we were trying to do, to get that critical feedback. It probably delayed some of the feedback that we could have gotten earlier about our first product—we eventually got there, but we might have been able to figure out some of the flaws with that idea earlier if we’d been more open.
The truth of the matter is, nobody’s going to steal an early-stage idea—there’s so much execution risk, and there are tons of ideas out there. If you’re able to give so much information in a single conversation that somebody else is going to take your idea, run with it and outcompete you, you were never going to win that race anyway. Not telling them was only delaying your loss in that race.
So you might as well just tell them and get that positive feedback. We have seen over and over again, telling customers, telling potential investors, telling potential employees very openly what we’re doing has led to all sorts of new ideas and benefits to us.
What about the broader vision for Antora? Do you have timelines, ultimate market size, other metrics that you think about, both in the near and the long term?
An Antora Energy demonstration unit being installed at an industrial site near Fresno, CA, USA. [Image: Antora Energy]
Our vision is that anytime you come across an industrial facility, you will see a thermal energy storage system next to it, that is converting renewable electricity into the power and heat that the facility needs 24/7. Hopefully, those are Antora systems, and hopefully, there will be a lot of other companies jumping into this space as well. The market is absolutely enormous. The market for industrial energy is in the trillions of dollars; it’s one of the biggest things that we do as a society.
As far as how we get there, right now, we’re really focused on the US market. There are a lot of tailwinds from the Inflation Reduction Act. And we’re looking forward to pretty large-scale commercial deployments starting in 2025.
Any other thoughts or observations you might share about your journey with Antora?
Well, one of the things that I’ll just mention that was quite enlightening was learning about graphite as an energy storage medium. We looked at candidates for thermal energy storage—graphite, and various types of rocks and bricks and molten iron and anything you could think of that was going to be cheap and store a lot of energy.
And we had actually discounted graphite early on, because we had made a mistake—in our modeling, we used the room-temperature specific heat of graphite, which is one-third of the specific heat when graphite gets to about 1000 °C.
So unlike almost any other material, between room temperature and high temperatures, graphite has this huge surge in specific heat capacity. It was a great example, I think, of always having to reevaluate and question your assumptions. Because we had looked at it and said, “Wow, graphite checks every box as a great storage material—except that its energy density, its specific heat, is just so low.” And then we thought, Are we sure that’s right? Why, from a fundamental physics perspective, would graphite be so much worse than other materials?
“Whatever we’re thinking right now, whatever we think we know, we’ve always got to be questioning those assumptions and not thinking that we have it all figured out.”—Andrew Ponec
And when we actually realized the mistake we had made, and flipped it around, graphite went from being a bad energy storage material to by far the highest-specific-heat material we could find that worked. So I think something that we always try to keep in the company is this humility. Whatever we’re thinking right now, whatever we think we know, we’ve always got to be questioning those assumptions and not thinking that we have it all figured out.