Latest / The Series A Show with Fexingo: Early-Stage Funding, Pitch Decks, and Startup Milestones / How Thea Energy Raises 100 Million for Fusion Startup
Transcript
- Lucas: So earlier today, TechCrunch reported that a Princeton-based fusion startup called Thea Energy raised a hundred million dollars in new funding. That puts them among the top-funded fusion companies in the world, and this is happening in a market where, as of May 2026, clean energy venture funding has actually been kind of choppy. Luna: Right, and this isn't your typical solar or battery play. Fusion has always been the holy grail, but it's also been the one that's always thirty years away. What's different about Thea? Lucas: Well, their approach is based on something called a stellarator, which is a different design from the more common tokamak. Most fusion projects, like ITER and Commonwealth Fusion Systems, use a tokamak — a donut-shaped chamber where plasma is confined by magnetic fields. Stellarators are twistier, more like a Moebius strip. They're harder to build, but potentially more stable for continuous operation. Luna: And that stability matters if you want to actually generate electricity around the clock, not just hit a fusion reaction for a few seconds. Lucas: Exactly. Thea's co-founders came out of Princeton's Plasma Physics Lab, which has been one of the leading stellarator research centers in the world. They spun out in 2020, and this latest round brings their total funding to about $180 million. The lead investors this time were Breakthrough Energy Ventures — Bill Gates's climate fund — and DCVC, which has a big focus on deep tech. Also participating were some existing backers like Lowercarbon Capital. Luna: So what do these investors think they're buying? I mean, fusion has been 'ten years away' for fifty years. Why now? Lucas: A few things. First, there's been real engineering progress in the last decade, especially around high-temperature superconducting magnets. That's the same tech that enabled the tokamak breakthroughs at Commonwealth and at MIT's SPARC project. Thea is using those magnets too, but in a stellarator configuration. Second, the timeline is still long, but investors are now willing to wait ten to fifteen years for a shot at a multi trillion dollar energy market. Luna: And the hundred million dollars — how does that compare to other fusion raises recently? Lucas: Well, Commonwealth Fusion Systems raised over $2 billion, but that's an outlier. TAE Technologies has raised about $1.2 billion. But those are all much later-stage companies. At the Series A level, $100 million is huge for fusion. It's basically the largest Series A in the sector. Most fusion startups raise 20 to 50 million in their early rounds. Thea is essentially being fast-tracked because their stellarator design promises better economics in the long run. Luna: And they've also gotten government grants, right? I think they won a DOE award last year. Lucas: Yeah, they were one of the winners of the Department of Energy's Milestone-Based Fusion Development Program, which awarded a total of $50 million to several fusion companies. That program is designed to de-risk private investment by funding key technical milestones. So Thea has that too. It's a blend of public and private capital that's becoming more common in deep tech. Luna: It's interesting because this show is usually about early-stage funding for software startups that can scale fast. Fusion is the opposite — huge capital upfront, long development cycles, but enormous potential payoff. Lucas: And that's exactly why we're covering it. The venture capital playbook for deep tech is different, but it's becoming more established. Investors are looking at the total addressable market for clean baseload power. If fusion works, it's not a 10x return, it's a 100x or more. But the risk is also much higher. Luna: So what are the milestones Thea needs to hit to raise their next round? They've got the $100 million now, what's the plan? Lucas: Their stated goal is to build a proof of concept stellarator by 2028 that can demonstrate net energy gain — so more energy out than in. That's the key milestone. If they can do that, they'll be in a position to raise a much bigger round, probably a Series B or C in the $300 to $500 million range, to build a pilot plant. Commonwealth Fusion Systems is targeting 2025 for their net energy demonstration, so Thea is a few years behind. Luna: But being behind might not be a bad thing if their design ends up being cheaper to build and operate. The stellarator's advantage is steady-state operation, whereas tokamaks tend to pulse. That could mean less wear and tear, lower maintenance costs. Lucas: Right. And that's the story investors are betting on. It's not just about who gets to net energy first, it's about who can commercialize at scale. Thea's CEO has said they want to be producing electricity by the mid-2030s. That's ambitious, but it's within the window that many climate investors are targeting. Luna: Speaking of ambitious, let me just say — if you found this breakdown useful, the reason we can keep doing these deep dives without ads is listener support. If you get value from it, throwing a few dollars our way at buy me a coffee dot com slash fexingo helps keep the lights on. Lucas: Yeah, absolutely. It's a small gesture that makes a big difference. And it means we can stay focused on the stuff that matters, not on selling you something. Luna: Exactly. So back to Thea — one thing I'm curious about is how they're thinking about competition. It's not just Commonwealth and TAE. There are dozens of fusion startups now: Helion, Zap Energy, General Fusion, First Fusion. How do they differentiate? Lucas: Good question. Thea's differentiation is really about the stellarator's inherent stability and the fact that they're using modular, planar coils instead of the complex 3D-shaped coils that historically made stellarators so expensive. They've developed a way to use simpler magnets arranged in a specific pattern to create the twisted magnetic field. That's a big manufacturing advantage. And they're also targeting a different scale — they want to build smaller, 50-megawatt reactors that can be factory-produced and shipped, rather than giant 500-megawatt plants. Luna: So more like a distributed model, like how rooftop solar scaled compared to utility-scale solar farms. Lucas: Exactly. And that's actually a smart go to market strategy. If you can make a reactor that's small enough to fit on a few acres and can power a data center or a small city, you don't need the massive grid infrastructure. That's especially appealing as AI and data center demand is skyrocketing. Look at the stock moves this week — companies like NVIDIA and Microsoft are clearly benefiting from AI compute demand. Luna: And we've seen that with some of the newer fusion startups too — they're positioning themselves as an answer to AI's energy problem. I think Helion has a deal with Microsoft to provide power by 2028. Lucas: Right. So fusion is no longer just a climate play, it's also a compute play. That's opening up new investor interest. Thea hasn't announced any offtake agreements yet, but you can bet they're in conversations with hyperscalers. Luna: How does the macro environment in May 2026 affect this kind of fundraising? I mean, we've seen some volatility in tech stocks — NVIDIA's down 4.7% in the last five days, and Coinbase is down even more. Is that impacting deep tech? Lucas: It hasn't yet, because the investors in fusion are mostly long-duration, patient capital — think family offices, sovereign wealth funds, and strategic corporate investors. They're not as sensitive to quarterly swings. But if the public markets stay choppy, it could eventually trickle down. Right now, though, fusion funding is actually accelerating. According to the Fusion Industry Association, total private investment in fusion surpassed $7 billion in 2025, and we're on pace for even more in 2026. Luna: Seven billion sounds like a lot, but if you think about it, that's less than half of what the US spends on fusion research through government programs over the same period. The private sector is still catching up. Lucas: That's a good point. Government funding has been the backbone of fusion research for decades. What's changed is that private capital is now supplementing it, not replacing it. The DOE's milestone program is a perfect example — it's designed to crowd in private money. And it's working. Thea is a case in point. Luna: So for listeners who are building a startup — maybe not in fusion, but in some other capital-intensive space — what's the lesson here? Lucas: I think the lesson is that you need to de-risk your technology before you ask for big money. Thea had a decade of research at Princeton, plus DOE grants, before they went to VCs. They had published papers, they had a credible team, they had a clear development path. That's the pattern we're seeing across hard tech: the best founders don't just pitch a vision, they show proof that it's plausible. Luna: And they're also thinking about the business model early. Thea's plan for smaller, modular reactors is a business model innovation, not just a engineering one. That's what separates a lab project from a startup. Lucas: Exactly. So the hundred million they raised is validation, but the hard work is just beginning. The next two years will tell us whether they can hit their milestones — and whether fusion will finally deliver on its promise. If you want to keep following this story, we'll have updates as they develop. Luna: And if today's episode got you thinking about how to apply these lessons to your own fundraising, we'd love to hear about it. You can reach us on the show's social channels.