This company says nuclear fusion could finally power the grid — and soon

By Ella Nilsen, CNN

(CNN) — A Massachusetts-based fusion company took another step this week in its race to become the first to get the same power fueling the sun and stars onto the US electrical grid.

Commonwealth Fusion Systems is currently building a donut-shaped machine called a tokamak — a chamber where atoms are smashed together in 100-million-degree plasma. The nuclear fusion reaction, forcing two atoms to merge, creates heat energy in the same way as the sun. It’s the polar opposite of conventional nuclear energy — a fission reaction that splits atoms. And it could be the key to unlocking nearly limitless power, all without nuclear waste or greenhouse gases that warm the planet. Fuel for fusion is abundant. It’s derived from deuterium, found in seawater, and tritium, which is extracted from lithium.

The company’s demonstration tokamak in Massachusetts is 75% built and slated to be operational by late next year. If it can successfully achieve net energy — producing more energy than what gets put in to run it — Commonwealth’s next step is building a 400-megawatt fusion power plant in Virginia. That will be named the Fall Line Fusion Power Station, the company announced Tuesday.

If they are successful, it would be a monumental achievement, decades in the making. Scientists in Europe and the United States have made a series of breakthroughs on fusion over the last few years, demonstrating a net energy gain is possible.

The big challenge that remains is sustaining it long enough to power electric grids and heating systems around the world. Some experts believe that is still many years away, but Commonwealth Fusion CEO Bob Mumgaard and others think the timeline could be shorter.

Building the first full-scale fusion power plant also means Commonwealth is the first company taking steps to get that kind of generation onto the US electric grid. On Tuesday, it announced it has applied to the nation’s largest grid operator, PJM, to connect its future plant into the network of wires and other infrastructure that controls electricity as it moves from power plants to homes and businesses. That application process will take years to complete, and the company is aiming to get its power onto the grid by the 2030s.

“Even though fusion might feel like it’s far off, it’s actually not that dissimilar a timeline from any of the other energy sources that people are talking about,” Mumgaard told CNN. For instance, the current wait times to build the gas turbines that power gas-fired plants are more than five years due to insatiable demand filling manufacturers’ order books.

The CEO acknowledged it’s still not certain fusion power can become a reality and is in “active development.”

“Most technologies that are impactful actually go from impossible to inevitable very quickly,” he said. “Look at what’s happening right now; what’s in the ground, where the smartest people are going, where the money is going.”

Despite its futuristic power supply, the process of connecting a fusion power plant to the grid isn’t actually much different from connecting other types of power, whether it be conventional nuclear, coal or renewables, said Rob Gramlich, CEO of consulting firm Grid Strategies LLC. A 400-megawatt power plant is “not that big relative to other power plants on the system,” has similar capacity to a gas plant and is smaller than nuclear fission reactors and most coal plants. And the electricity itself is made similarly to existing technologies: Hot water creates steam to turn turbines that create electricity. The difference is just in how to heat the water.

“I don’t think there’ll be anything super tricky,” Gramlich said. “I don’t see any reason why the grid couldn’t handle it.”

In addition, the small amount of fuel needed for small nuclear plants — whether fission or fusion — give them the advantage of being easier to construct in more population-dense areas, closer to existing grid infrastructure, Gramlich said.

“You have the opportunity to put them close to load, put them close to the data centers, and sometimes closer to where people live,” Gramlich said. If “you don’t have the vast land expanse of, say, West Texas. You can fit a lot of power in a small area.”

Mumgaard said most of PJM’s questions so far have centered on how much fuel the power plant will need on site, how much power and lead time it will need to turn on and how intermittent the power itself will be.

The application process with PJM takes four to six years to complete. Mumgaard said his company has been engaging with PJM for two years already before formally submitting their application.

A PJM spokesperson didn’t comment directly on Commonwealth’s application but said the grid operator was “excited about the diversity of resources that have applied to connect to the grid.”

The power the Virginia fusion plant will generate already has two buyers: Google and energy company Eni. That means the construction of the power plant and infrastructure to connect it to the grid won’t impact rates of everyday businesses and consumers.

“That was really important; a first-of-a-kind power plant, you don’t want to have the ratepayers on the hook for that,” Mumgaard said.

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