CFS Secures $863 Million to Accelerate Fusion Toward Commercial Reality

Massachusetts-based fusion startup Commonwealth Fusion Systems (CFS) has raised $863 million from a broad list of investors, including Google, Nvidia, Breakthrough Energy Ventures, and others. This funding reflects increasing confidence in fusion as a future energy solution.

Co-founder and CEO Bob Mumgaard said, “This round isn’t just about fusion as an idea—it’s about making it a commercial industrial endeavor.” CFS has now raised nearly $3 billion, the largest total for any fusion startup worldwide.

The company is developing the Sparc reactor, a tokamak prototype designed to demonstrate net energy gain. Sparc is expected to start operations in 2026, with scientific breakeven projected for 2027—producing more energy than it consumes to ignite the plasma.

Although Sparc won’t sell electricity to the grid, it will validate technology, estimate costs, and build operational expertise. Following Sparc, CFS plans to construct Arc, its first commercial-scale fusion plant in Virginia in 2027–2028. The diverse group of investors will help with supply chain development and partnerships to support industrial-scale fusion.