Investing in Helion: Abundant Intelligence Requires Abundant Energy

We’re entering an age where AI workloads, data centers, and industrial processes demand constant, high-density electricity. Global energy consumption, according to OWID, is on an exponential curve–mirroring GDP growth and driven by reshoring, AI, and the constant expansion of digital infrastructure. The global power generation market is projected to surge from $2T to nearly $4T by 2032, with industry alone consuming 30% of that demand.

AI training and inference are also on track to double their electricity needs in the next two years. Because AI data centers operate 24/7, they require baseline power solutions beyond the reach of intermittent renewables.

Amid this industrial renaissance, we need new solutions that are not just clean but can also deliver always-on, cost-competitive power at scale.

Fusion as the ultimate energy source

Fusion offers what every industrial economy craves: abundant baseload power without the drawbacks that plague conventional energy sources. Essentially, all the power we’ve ever harnessed—from fossil fuels to solar—originates from the same reaction that occurs in the sun. Fusion is that core reaction, replicated here on Earth.

Unlike other approaches, fusion doesn’t risk runaway reactions or generate high-level waste. Its byproduct, helium, is inert. It also doesn’t require fissile material, which eases proliferation concerns. On top of that, fusion is extraordinarily energy-dense–ten percent of the material resources, one percent of the land footprint, and none of the storage headaches that renewables demand.

The math is profound: if deuterium (one of the key fusion fuels) is harvested from seawater, about 10 Olympic pools worth of saltwater could power the world’s annual energy consumption. That sheer abundance is why many call fusion the “holy grail” of energy.

Fusion is possible

For decades, fusion existed largely in national labs, where massive experiments tested if humanity could ever replicate the sun’s process on Earth. That paradigm changed in 2022, when the National Ignition Facility (NIF) achieved net gain (Q Plasma), proving that fusion reactions can produce more energy than they consume at the reaction level.

Amid this momentum, Helion has quietly achieved unprecedented breakthroughs of its own. Chief among these is Helion’s pulsed-fusion prototype, Trenta, which reached plasma temperatures in the 100 million degrees Celsius range—one of the key benchmarks on the path to commercial fusion. Through thousands of test pulses, Helion refined critical elements of their pulsed-magnetic fusion approach and saw evidence of bulk deuterium-helium-3 fusion.

Lessons from Trenta directly informed Polaris, Helion’s next-generation prototype designed to create electricity from fusion—another milestone only a handful of fusion concepts have approached. Polaris will pulse faster than Trenta and serve as the blueprint for Helion’s eventual commercial plant, bringing the company closer to delivering a new era of fusion energy.

Regulatory developments are also catching up. Fusion is now supervised more like an MRI machine than a fission plant, opening a simpler, faster path to deployment.

For the first time, building a net-energy, commercial-scale fusion reactor seems achievable within venture timelines. Following our Pacific Fusion investment earlier this year, we’re excited to continue to invest further in the space.

Why Helion

Helion is pushing toward commercial fusion electricity production with a distinctive fusion engine that targets high energy efficiency and minimal electron losses. By using a less-neutronic fuel cycle (deuterium-helium-3) and bypassing traditional heat engines, Helion aims to streamline the path from plasma confinement to electricity generation. Their target is demonstrating electricity with their newest prototype, Polaris, in the near-term, and building and operating a fusion power plant by 2028.

When we first met Helion, we were immediately taken by the caliber of their founding team, led by David Kirtley, who has been on this mission for over 15 years. His track record—assembling impact-driven, interdisciplinary scientific teams to tackle society’s toughest challenges—made him an ideal leader to drive Helion forward.

It’s a bold vision. Achieving these milestones means tackling complex plasma stability conditions, maintaining very high efficiencies, and pioneering advanced power-conversion methods—all at once. Yet if Helion succeeds, the payoff could be revolutionary, radically lowering the cost and complexity of fusion power plants.

Looking ahead

At Lightspeed, we invest in disruptive technologies that don’t just transform markets but redefine them for all time—just as we’ve done with AI. We believe fusion sits on the cusp of a breakthrough of that magnitude, and Helion is clearly leading the charge.

Helion embodies our belief that industrial-scale fusion is no longer a distant aspiration, but rather an engineering milestone in our purview.

We couldn’t be more excited to invest in Helion’s $425 million Series F, alongside Sam Altman, Softbank Vision Fund 2, Mithril Capital, Capricorn Investment Group, and others. Helion is led by a visionary team that recognizes tomorrow’s AI-driven world demands a new kind of baseload power—cheap, emission-free, and globally scalable.