An MIT spinoff will soon begin construction of a research facility at Devens to house development of a nuclear fusion device that could revolutionize the way electricity is generated.
Commonwealth Fusion Systems of Cambridge announced March 3 that it has chosen a 47-acre site on Hospital Road across from New England Studios for a 165,000-square-foot manufacturing plant and headquarters and a 150,000-square-foot research facility, where it intends to build the first fusion reactor capable of generating more energy than required to run it. Construction of the plant and headquarters is expected to begin this month.
Proposed fusion plant campus.(Courtesy photos)
According to a company press release, the Commonwealth campus will be home to a compact net-energy fusion device, dubbed SPARC (Soonest/Smallest Private-Funded Affordable Robust Compact), that its developers hope will be the first to demonstrate that fusion can work as a commercial power source, one that delivers two to 10 times the amount of energy needed to sustain it.
Fusion power releases no carbon dioxide and has been touted for decades as a potential clean energy replacement for current coal-, oil-, and gas-burning power plants. Fusion produces a fraction of the radioactive waste left by today’s fission reactors and does not create materials that can be used to construct nuclear weapons.
Commonwealth, a 2018 spinoff of MIT’s Plasma Science and Fusion Center in Cambridge, is among nearly two dozen startups in the U.S. and elsewhere rushing to commercialize recent advances in fusion technology, most notably the availability of so-called high-temperature superconducting wires. Constructed of materials that can operate at temperatures closer to that of liquid nitrogen (approximately -200 degrees Celsius), these ribbon-like wires will enable the construction of more powerful magnets, capable of containing a self-sustaining fusion reaction within a smaller vessel than previously possible.
Cross section of CFS design for super-conducting magnet, drawn to scale.
Several hurdles remain. First the company must demonstrate its new magnet will work as designed. A test is scheduled at MIT in June. Commonwealth CEO Bob Mumgaard was quoted in a March 12 Science magazine article as saying that the 2.5-meter-tall, D-shaped magnet would be the largest high-temperature superconducting magnet ever built. “It’s a big deal,” he said. If the magnet works, “then our device will work,” a Commonwealth spokesperson predicted recently.
Once the magnet is proved viable, Commonwealth will start construction of its SPARC reactor, aiming to fire it up by 2025. The magnets for that device will be assembled in the manufacturing plant at Devens, while the device itself—two stories high and occupying the area of a tennis court—will be built in the research facility. If SPARC performs as hoped, then Commonwealth would scale up to become a manufacturer of commercial-grade fusion-driven power plants that could, by 2035, deliver as much energy as a medium-sized conventional system that burns fossil fuels.
On Jan. 19, exactly 60 days after accepting Commonwealth’s applications for review, the Devens Enterprise Commission, the licensing authority for Devens, voted unanimously to grant the company permission to proceed, contingent on its meeting 28 conditions, most related to development of the site on Hospital Road and mitigation of operational noise. The company did not appeal any of the DEC’s requirements.
Although a final purchase and sale agreement for the Devens property was still pending on Tuesday, company spokesperson Kristen Cullen said Commonwealth expected to break ground for the manufacturing and headquarters facility as early as April. The company will require two additional licenses from the state by the start of operations in 2025: one for the storage and use of tritium, a radioactive isotope of hydrogen used to fuel the reactor, and one for the SPARC device itself.
Town officials were notified of Commonwealth’s plans by the DEC in November 2020—as required by state law—but the project got its first public airing in Harvard only two weeks ago at the March 16 meeting of the Select Board, where Cullen and Tyler Ellis, a Commonwealth scientist, explained the project via Zoom to board members and a small audience.
Cullen told attendees the company has grown from 10 to 150 employees since its founding, and she expects employment at the Devens facility to grow to between 300 and 500 jobs by 2025. “These are not just jobs for MIT plasma physicists and those who study fusion,” she said. There will be new jobs in manufacturing, engineering, and operations. The company is well funded, having raised $250 million from investors that include Bill Gates, Jeff Bezos, and the European energy companies Eni and Equinor.
During the Q&A session that followed, Harvard-Devens Jurisdiction Committee member Paul Green asked what factors had driven Commonwealth’s decision to locate at Devens. Cullen said the company had looked at sites in Tennessee, New York, and North Carolina for two years, but settled on Devens because of its proximity to MIT, in spite of lucrative financial incentives offered elsewhere.
The fast permitting process offered by Mass Development was attractive as well, she said. “The whole purpose behind why we founded this company is we want to develop and bring a new clean energy technology to the world, in a time frame that actually matters for climate change. And from all the reports that we read, if you’re not putting actual clean megawatts on the grid by the 2030s, it’s pretty tough to argue you’re gonna be relevant for climate change,” said Cullen. “You’re kind of too late.”
Green also wanted to know whether Commonwealth was aware its plant would be built on historic Harvard land that could be returned to town jurisdiction in 2033. Cullen said the company was aware of the issue. “I don’t think we have any immediate concern,” she said. “We’ll be watching how things go.”
Select Board member Stu Sklar and Charles Agosta of Bolton Road, a professor of physics at Clark University who has worked with superconducting magnets, had questions about the safety of the research facility, including the storage of tritium, and the consequences of a sudden failure of the SPARC reactor’s magnetic field. Ellis noted that operating SPARC would require no more than a U.S. quarter-sized amount of tritium, which is commercially available and not highly radioactive. In the event power was lost, he said, the reactor would shut down in less than a millisecond. “It’s like a finicky machine that wants to be off,” said Ellis.
Agosta later told the Press that he didn’t think SPARC would pose any special safety concerns. He said company engineers would have to deal with the conventional problems of any large plant. There’s lots of electricity involved and the storage of large amounts of liquid nitrogen can be dangerous, he said. But drug manufacturers often have huge tanks of liquid nitrogen outside their manufacturing plants. “[The Commonwealth facility] is not a commercial-size plant. That’s one of the main things. It’s a research facility.”
Cullen and Ellis predicted the work at Devens will draw scientists and politicians from around the world. But it could also prove to be a great destination for school kids and college students, Agosta told the Press this week. He would definitely bring classes there. “It is a novel, state-of-the-art, possibly world-changing piece of technology. That part is really exciting.”