Helion’s Blueprint – Achieving Affordable and Abundant Fusion Energy

Fusion energy has long been a distant dream. Despite decades of research and billions of dollars invested, the promise of clean, limitless power from nuclear fusion has remained just out of reach. Since the mid-20th century, scientists have pursued this goal with determination, yet the field has become known for its repeated delays—often summed up by the joke that “fusion is always 30 years away.”

The challenge lies not in the idea, but in the execution. While the physics behind fusion is well understood, turning that knowledge into a practical, commercially viable energy source has proven incredibly difficult. Most efforts have been massive, government-led projects that, while scientifically valuable, have yet to produce a working fusion power plant.

And among the nuclear fusion startups, the one that has attracted the biggest attention is Helion Energy. Despite the immense technical and financial challenges that might discourage even the most determined entrepreneurs, Helion was still born—driven by a bold vision to change the future of energy.

Everything Has Stated Under the Stars

David Kirtley’s journey toward founding Helion Energy didn’t begin in a lab—it started under the stars.

Growing up in a Navy family, he moved every three years, one of which brought him to the Bermuda Naval Air Station. There, as a 10- or 11-year-old, he would watch night launches of the space shuttle streak across the sky—a glowing, man-made comet lighting up the darkness. It was a powerful moment: seeing something humans built soaring into space. That early image sparked something in him, even if he didn’t yet know how to act on it.

“Now at night, you could see when they did night launches, this man-made comet flying above you and just lighting up the sky and looking like, hey, we humans built this thing. There are people up there and they’re going into space like technology can do this thing. I want to follow this. But I don’t know how to apply it yet,” he recalled.

In high school, David’s passion for physics was sparked by an AP Physics teacher who had worked on the Superconducting Supercollider. This teacher brought science to life—not through abstract theory, but through real-world experiments like fireworks, roller coasters, and data collection. For David, physics became a way to understand the universe through rules and patterns. The hands-on approach, blending curiosity with application, left a lasting impact and helped shape his future path.

By the 1990s, as a high schooler with an engineering mindset, David saw energy—not climate, but geopolitics and stability—as the world’s biggest challenge. Realizing that all energy traces back to fusion, he believed humanity could replicate it.

But there was a catch: David couldn’t afford the elite schools where he believed fusion research happened. So, he started at the University of Texas at Dallas, studying electrical engineering and building his core understanding. After two years, he transferred to the University of Michigan to complete his degree, where he joined research on plasma physics, plasma thrusters, and even antimatter-based fusion (muon-catalyzed fusion). His very first technical paper was on that topic.

Despite his early progress, David reached a turning point. Fusion, he realized, was likely decades away from powering the grid—maybe beyond his lifetime. Still passionate but pragmatic, he pivoted to spacecraft propulsion, applying his plasma physics background at the Air Force Research Labs, where he worked on Hall-effect thrusters later used in Starlink satellites.

Curiosity pulled him back to grad school, where he earned master’s degrees in nuclear engineering, plasma physics, and aerospace engineering. Though focused on propulsion, fusion remained on his mind. After his PhD, while working on plasma thrusters, he met the future Helion founding team—who introduced him to engineering ideas that could speed up fusion’s timeline dramatically.

That was the breakthrough moment. It wasn’t just about theory anymore—it was real, applied, and achievable within a timeline that mattered. They could build actual machines. They could do fusion now.

So David and the team made the leap. In 2013, David Kirtley, along with John Slough, Chris Pihl, and George Votroubek, co-founded Helion Energy. They began building early prototypes, validating the physics, and demonstrating real fusion. Fueled by personal urgency, scientific ambition, and global necessity, they committed to bringing fusion to life—not in some distant future, but on a timeline meaningful to both humanity and themselves.

“That’s where I got the bug and said not only can we do space propulsion, that’s great, with this physics and engineering, but maybe we actually have a chance to do fusion on time scales that are relevant for humanity, relevant for me personally. Frankly, it’s relevant for me personally. We were able to build those early machines, and do fusion. Then I said, great, let’s go do this, and we focused all of our efforts on forming Helion and moving from there,” he said.

What Makes Helion Energy a Revolution?

Leveraging cutting-edge magneto-inertial fusion technology, Helion has already achieved significant milestones with its Trenta prototype, which reached 100 million degrees Celsius—a key threshold for fusion. The company is now advancing its Polaris project, designed to be the first fusion system to generate electricity directly, marking a major step toward sustainable, carbon-free energy for the future.

To understand what sets Helion apart from other competitors and appears as an disruptor in cleantech, we need to look at several things.

Direct Energy Recovery

According to David Kirtley, traditional magnetic fusion, like that used in tokamaks, confines hot plasma using strong magnetic fields, maintaining stability long enough for fusion to occur. The resulting heat is then used to boil water and generate steam to drive turbines, much like conventional power plants. Inertial fusion, on the other hand, uses extremely short, intense bursts of energy—typically from lasers—to rapidly compress fusion fuel, creating a supernova-like effect. This also produces heat, which is again converted into electricity through steam turbines.

Helion Energy takes a different path by combining aspects of both magnetic and inertial fusion while introducing a breakthrough in energy conversion.

“What we do is something that takes some of those, the best of both, the physics of both, but then new engineering to do what we call direct energy recovery,” David stated.

Their system traps plasma in magnetic fields and compresses it quickly to trigger fusion. However, instead of relying on heat to produce steam, Helion captures the energy directly from the fusion reaction itself. As the plasma pushes back against the magnetic field during fusion, that force is converted straight into electricity—bypassing the need for steam turbines entirely and offering a more efficient and compact solution for clean energy generation.

To make that level of efficiency possible, David says that Helion has been meticulous about every engineering detail from day one. Even small components like electrical connectors are carefully designed, tested, and stress-tested to understand their limits. That rigorous mindset, he explains, came in part from early team members who had worked in the space industry, where precision is everything and even minor inefficiencies can cause huge problems.

Small, Efficient Systems Designed for Speed

One of the biggest lessons he’s learned is that big machines aren’t just linearly more difficult—they’re exponentially harder to build and manage. A machine that’s 10 times larger might be 100 times more difficult to engineer. And when you layer in the challenges of raising capital, working with international partners, and navigating political processes, the timeline and complexity can become unmanageable.

That’s why he’s become such a strong believer in Helion’s strategy of building small, testing early, and iterating fast. Instead of jumping straight to massive fusion reactors, they validate small systems first, learn from them, and scale up from there. It’s a faster, smarter, and ultimately more reliable path—and one he admits he wouldn’t have predicted early in his career, but now sees as essential to Helion’s success.

Building on the Shoulders of Giants

David Kirtley believes innovation doesn’t always come from starting from scratch. Early in his career, he saw a common push—especially in academia—to pursue entirely original work in isolation, often disconnected from past knowledge or practical application. At Helion, he took a different path.

Instead of reinventing the wheel, Helion builds on decades of proven physics and engineering, much of it dating back to the 1950s. What they’ve done is combine that foundation with modern technologies—like advanced electronics and fiber optics—to finally realize ideas that were once only theoretical.

“I think that’s something that at Helion, with our fusion systems, we have looked at—that they’re built on physics and engineering that go back to the 50s. And it needed new electronics and new fiber optics and all kinds of new technologies to be able to build the systems people had theorized, but it wasn’t us starting from scratch,” he explained.

He often references the idea of “standing on the shoulders of giants”—and credits large-scale programs like the space shuttle for showing the power of collaborative, incremental progress. That thinking continues to shape how he builds teams and leads Helion today.

How Did David Kirtley Build His Team?

David Kirtley explains that at Helion, they look for candidates who can contribute across three core areas: theory, experimentation, and hardware/computation. During interviews, they often ask where someone falls on that spectrum—what they’ve focused on in their career, and what excites them going forward. They value people who have range, even if they lean more heavily toward one area. Ideally, team members can do a bit of everything.

This multidisciplinary approach is essential at Helion because building real fusion systems requires a mix of skills. You need theory to make the science work, simulation and computation to avoid constant trial-and-error, and hardware skills to physically build and test the systems. No one discipline is enough on its own.

David ties this back to his own journey. He got into fusion because he loved building and testing things. But early on, the field felt too theoretical and too long-term, which made him question if it was the right path. He eventually paused to reassess and figure out what really motivated him. That experience shaped his belief that people do their best work when they’re passionate—and when they get to apply their skills in a tangible way.

An Idea that Big Guys Bet on

David Kirtley’s belief in hands-on learning started in high school—he needed to build and test things to truly understand them. That mindset carried into his early fusion work, where he and a small team built a compact fusion device in a warehouse using ideas from the 1950s. On a $1.5 million budget, they achieved real fusion reactions—outperforming many billion-dollar efforts.

“We did that on the program that was like $1.5 million but was outperforming certainly every private fusion company that had come before. But then most of the national labs, even up to the billion dollar scale lab. We said like, wow, okay, we’re seeing an approach that can do fusion at a really interesting scale, still not at commercial scale, but for three orders of magnitude less money,” David said.

From that experience, he learned a critical insight: the cost of research often determines the cost of the final product. If you can prove a concept cheaply, you have a better chance of building an affordable, scalable system. But billion-dollar R&D often leads to overbuilt, commercially unviable systems.

With scientific results in hand, a plausible path to scale, and a clear commercial vision, they spun out Helion. They raised venture capital—first from Mithril Capital and Y Combinator—and began building bigger machines.

As of 2025, Helion Energy is in a strong financial and developmental position, marking a pivotal year in its journey toward commercial fusion energy. The company has raised over $1 billion in total funding, with a significant boost coming from a $425 million Series F round in January 2025. This round brought Helion’s valuation to approximately $5.42 billion.

Key investors include prominent figures and organizations such as Sam Altman, SoftBank Vision Fund 2, Lightspeed Venture Partners, Capricorn Investment Group, Dustin Moskovitz, and Nucor, reflecting strong confidence in Helion’s vision and technology.

On the technical front, Helion achieved a major milestone with the launch of its seventh-generation fusion prototype, Polaris. This prototype is expected to be the first to generate electricity directly from fusion, a significant leap forward in the field. In parallel, Helion secured a Power Purchase Agreement (PPA) with Microsoft to deliver 50 megawatts of fusion electricity by 2028, signaling commercial readiness. Additionally, the company partnered with Nucor to develop a 500 MW fusion power plant in the 2030s, further expanding its long-term impact.

To support these advancements, Helion has also begun manufacturing critical components like capacitors and magnetic coils in-house. This move is aimed at scaling production efficiently and reducing reliance on external suppliers.