CFS was founded in 2018 as a spin-off from the
MIT Plasma Science and Fusion Center. After initial funding of $50 million in 2018 from the
Italian multinational
Eni,
Bill Gates's
Breakthrough Energy Ventures,
Vinod Khosla's
Khosla Ventures, and others. CFS raised an additional US$ 84million in series A2 funding from
Singapore's
Temasek,
Norway's
Equinor, and Devonshire Investors, as well as from previous investors. In September 2020, the company reported significant progress in the physics and engineering design of the
SPARC tokamak, and in October 2020, the development of a new high temperature superconducting cable, called VIPER. Over the 9-month period from 2019 to 2020, the company purchased over 186 miles of the wire in 400-600 meter lengths from vendors, more than was produced by some vendors over the preceding 6 years. In March 2021, CFS announced plans to build a headquarters, manufacturing, and research campus (including the SPARC tokamak) in
Devens, Massachusetts. In the same year, CEO Bob Mumgaard was appointed to the board of directors of the
Fusion Industry Association, which was incorporated as a non profit association with a focus on combating
climate change. Later in September 2021, the company announced the demonstration of a
high temperature superconducting magnet, able to generate magnetic fields of 20 tesla. The company raised an additional $1.8 billion in Series B funding in November 2021, to construct and operate the SPARC tokamak. This was funded by
Temasek Holdings,
Google,
Bill Gates and
Eni. By late 2022, CFS had grown to approximately 350 employees and was preparing to move into its Devens campus. A ceremonial opening for the Devens campus was held in February 2023. In March 2023, Eni and CFS signed a multi-year agreement to collaborate in obtaining the components and authorizations necessary for the construction of the first SPARC experimental plant, as well as the construction of the first Arc power plant and the identification of countries that may be interested in hosting it. In May of that year, the
United States Department of Energy granted the company additional funding along with seven other US companies via the
Milestone-Based Fusion Development Program. The following year, in 2024, CFS announced plans to build the world's first grid-scale commercial nuclear fusion power plant at the James River Industrial Center in
Chesterfield County, Virginia. The plant will produce about 400 MWe. The company plans to build it by the early 2030s. Google announced in July 2025 that it had signed a direct corporate power purchase agreement, a first of its kind, with CFS. The agreement will give Google 200 megawatts of power from CFS’s ARC project in Virginia. Later in August, CFS announced $863 million had been raised in a Series B2 round. In September 2025, Eni made a $1 billion deal with CFS to use power from its first fusion reactor. == Technology ==