Fusion energy is a critical technology for addressing the global energy transition, providing a source of clean, abundant, and reliable power without the challenges of traditional nuclear power or variable renewable energy.
It comes as no surprise then, that the race to develop fusion energy is intensifying, with China, the UK, and other global powers making major investments in the technology. The U.S., too, invested significantly into the technology, with several key milestones achieved in recent years, including the Lawrence Livermore National Laboratory’s demonstration of net energy gain from a fusion reaction. However, that investment has declined significantly of late.
At the forefront of American companies driving these milestones is Commonwealth Fusion Systems (CFS), the world’s leading and best-capitalized fusion energy company. Since CFS was founded in 2018, the company has grown to 1,000 employees and raised over $2 billion.
“If you look at the energy transition, that is the largest change in how humans organize themselves from an economic and industrial point of view. The numbers are staggering — the energy transition will touch every single person's life because every single person uses energy,” says Bob Mumgaard, CEO and Co-founder of CFS.
Mumgaard, who earned a PhD in Applied Plasma Physics from the Massachusetts Institute of Technology, spoke about the progress and obstacles facing fusion energy during an event hosted by Columbia Business School’s Tamer Institute for Social Enterprise and Climate Change and the School’s Distinguished Speaker Series.
In a conversation with Professor Bruce Usher, Co—Director of the Tamer Institute and Elizabeth B. Strickler '86 and Mark T. Gallogly '86 Faculty Director, Mumgaard laid out three key insights into the opportunities and challenges facing the clean energy transition.
1. A New Space Race
Mumgaard underscored the high—stakes global competition for fusion energy development, noting that while the U.S. once led the way in fusion innovation, its current investments lag behind those of China and, more recently, the United Kingdom. Chinese efforts, according to Mumgaard, are several times larger in funding and scale, positioning China as a formidable competitor in the race to deploy the first commercial fusion power plant.
Still, Mumgaard had some optimism about the future of the industry in the U.S. He noted that fusion is a top-four priority under the new energy secretary, joining other transformative sectors such as quantum computing and geothermal, though so far the Department of Energy hasn't taken any new action to boost it. The government’s evolving approach, including a move to regulate fusion machines like cancer treatment facilities and not like fission reactors, could prove pivotal in catalyzing innovation.
Mumgaard compares the current fusion race to the 20th-century Space Race—a new “moonshot” that could define global energy leadership.
One fusion energy benefit is its decoupling from traditional fuel resources. Unlike fossil fuels or even renewable sources that depend on geographical conditions, fusion offers a path to limitless, clean energy that is independent of traditional resource constraints. This potential has enormous geopolitical and economic implications, as it could fundamentally reshape global energy markets and reduce the leverage of current resource—rich regions, according to Mumgaard.
2. From Breakthroughs to Commercialization
Mumgaard identified six fundamental challenges that every fusion company must overcome to transform experimental breakthroughs in fusion energy into a viable, market—ready technology. They are:
1. Can your company produce stable plasma?
2. Can your company heat the plasma to 10,000,000 degrees C?
3. Is your plasma dense enough for fusion?
4. Can your plasma produce net energy gain?
5. Can your fusion machine (i.e. your entire plant) generate enough power to sell the excess?
6. Is your fusion power competitive with other power sources?
The type of machine CFS is using, called a tokamak, has achieved milestone 3, and with its own SPARC machine, CFS is making progress on milestone 4 — one that has eluded all but the Lawrence Livermore National Laboratory. SPARC is designed to be the first commercially relevant machine to demonstrate net fusion energy—producing more energy from the fusion reaction process than is used to heat the plasma.
While many experimental setups have demonstrated progress toward these milestones, only a select few have managed to create the conditions required for fusion that is both controlled and energy positive. Achieving these scientific breakthroughs is only part of the journey, however.
Turning these milestones into a commercial reality requires a different kind of innovation — a transformation from laboratory—-scale experiments to full—-scale, grid—-connected power plants. That requires work beyond science and engineering. CFS takes a vertically integrated approach that also encompasses the broader challenges of project finance, supply chain management, and regulatory approval. Mumgaard explains that while many fusion experiments have shown promising results, integrating this full suite of changes into an existing energy market will utterly transform power infrastructure.
“Fusion has pretty big strategic implications. Think about what fusion is — every energy source before was sort of hunter—gatherer mode. You went out, gathered a resource, dug it up and burned it, piped it, or you waited for the sun or wind to come over your advantageous geography. That’s a resource business. With fusion, you don’t collect anything — you’re building a machine, a technology. So it scales very quickly,” Mumgaard said. “And you get a new power plant that could seamlessly replace a traditional coal or gas facility, minimizing complications for the grid and utility companies.”
Instead of chasing entirely novel, untested concepts, CFS has opted for a strategy that minimizes discovery risks and emphasizes using well-understood fusion principles as much as possible.
In this way, Mumgaard explained that the company aims to de-risk the commercialization process, allowing for a smoother transition from experimental science to a sustainable, scalable product that can be economically competitive with other energy sources.
3. Leadership in a Transformative Industry
Mumgaard emphasized that true leadership in fusion — or any disruptive industry — requires the courage to continually “fire yourself.” The best leaders, according to Mumgaard, are those who recognize that there is always someone better equipped to take over particular areas, ensuring that the organization remains dynamic and forward-thinking.
At CFS, this leadership philosophy translates into a multidisciplinary approach. The team needs more than just nuclear engineers and plasma physicists; it also benefits from having professionals from sectors as diverse as pharmaceuticals, aerospace, and regulatory affairs. This broad talent base is essential for addressing the multifaceted challenges of building a commercial fusion power plant, from technical innovation and supply chain logistics to securing project finance and regulatory approval, according to Mumgaard.
Mumgaard stressed the importance of setting and achieving incremental milestones. By breaking down the monumental task of commercialization into smaller, manageable steps, companies can maintain momentum and investor confidence over the long term.
He also urged early-career professionals to pursue opportunities in growing fields where transformative change is on the horizon, rather than just in established sectors with increased potential for diminishing returns.
