Safar Partners Invests $100 Million in Portfolio Company Commonwealth Fusion Systems as they Commercialize Fusion Energy

Dec 3, 2021

Safar Partners, a seed- to growth-stage venture fund investing in technology companies, announced today that it is investing $100 million in portfolio company Commonwealth Fusion Systems (CFS). The funding is part of CFS’ Series B round that raised $1.8 billion when it closed on November 19, 2021

The Safar Partners investment will help support CFS’ efforts to construct, commission, and operate SPARC, the world’s first commercially relevant net energy fusion machine. In addition, it will enable the company to begin work on ARC, the first commercial fusion power plant, which includes developing support technologies, advancing the design, identifying the site, and assembling the partners and customers for the future of fusion power.

Last September, in partnership with MIT’s Plasma Science and Fusion Center, CFS successfully tested the world’s strongest high-temperature superconducting fusion magnet. This historic breakthrough in clean energy generation through commercial fusion paves the way for the future development of carbon-free, commercial power that could make a significant impact on the climate change crisis.

“We are thrilled to announce this new investment in Commonwealth Fusion Systems, a company that is leading the way in global clean energy,” said Nader Motamedy, a Safar Managing Partner. “Their breakthrough superconducting magnet is vital in the effort to develop carbon-free power plants that will transform our energy future. We are proud to continue our support as CFS works to achieve new energy milestones.”

The record-breaking CFS magnet is the product of three years of research, design, manufacturing, and testing to perfect the highly efficient technology. A September 5th test at MIT’s Plasma Science and Fusion Center demonstrated that, using a tiny fraction of the energy required in similar previous tests (30 watts as opposed to 200,000,000 watts), the CFS high-temperature superconductors (HTS) magnet can generate intense magnetic fields capable of producing net positive energy from fusion reactions.

Novel CFS magnets can create a powerful enough magnetic field to achieve net positive energy from fusion within a compact device known as a tokamak. Using new commercially available HTS to build high field magnets will enable the company to build smaller, more cost-effective tokamaks to deliver the fastest path to commercial fusion energy.

“For the first time, we have the technology that can enable us to produce clean, limitless energy from fusion power on a global scale,” said CFS CEO Bob Mumgaard. “Safar understands the power of fundamentally new technologies and their ability to transform our energy future. We are so grateful for their continued support, which enables high impact companies like ours to achieve breakthroughs that will have a lasting impact on future generations.”

CFS’ HTS magnet technology is used in “SPARC,” a compact fusion device which is under construction in Devens, Massachusetts and is on track to demonstrate net positive energy from fusion by 2025. SPARC will pave the way for the first commercially viable fusion power plant.

“Safar is honored to be an active partner in Boston’s thriving entrepreneurial ecosystem, which is producing innovative technologies and initiatives with positive global impacts,” said Arunas Chesonis, also a Safar Managing Partner. “Commonwealth Fusion was the first of Safar’s many investments in MIT ventures and spinout companies, and we are pleased to take our partnership with them to the next level.”

The investment in CFS from Safar Partners includes a significant position held by Hostplus, one of Australia’s largest pension funds and an anchor investor in Safar Partners.

“One of the best examples of our commitment to sustainability has been the partnership between Hostplus and Safar regarding our investment in Commonwealth Fusion Systems,” said David Elia, CEO of Hostplus. “Fusion energy on the scale required to significantly decarbonize our planet is why Hostplus will continue to support CFS and MIT.”

About Safar Partners
Safar Partners is a seed- to growth-stage venture fund investing primarily in technology companies out of MIT, Harvard, and the University of Rochester. Safar takes advantage of the principles of private equity to create value as our companies scale beyond initial prototypes. We accelerate the scaling of our portfolio companies through the formation of spinouts or joint ventures to address additional markets, industries, or geographies. For more about Safar Partners, visit

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