Commonwealth Fusion Systems
Commonwealth Fusion Systems is a Fusion Energy company founded in 2018 and based in Devens, USA. It has raised $6.9B in total funding, most recently a Series C in 2026.
Founded in 2018 and headquartered in Devens, USA, Commonwealth Fusion Systems develops fusion energy technology centered on proprietary 20-tesla REBCO high-temperature superconducting magnets that enable compact tokamak designs roughly 40 times smaller than conventional fusion reactors at equivalent power output. The company's SPARC demonstration device, under construction with operations targeted for 2026–2027, will validate the physics and magnet technology required for ARC, its planned commercial fusion power plant designed to generate 400 MW of net electricity. Google has committed to a 200 MW power purchase agreement for ARC output, with the plant sited in Chesterfield County, Virginia and first power targeted for the early 2030s. As of August 2026, CFS has raised $6.86 billion across multiple rounds, including a $4 billion Series C announced in August 2026, establishing it as a major recipient of private capital in the fusion energy sector.
Commonwealth Fusion Systems represents a significant concentration of private investment in fusion commercialization: its $4 billion Series C in August 2026 occurred amid a broader surge in private capital flowing into fusion energy startups building commercial reactors. The company's combination of DOE-validated magnet technology, a near-term demonstration device, and a commercial power purchase agreement with Google signals tangible progress toward grid-connected fusion power generation. The scale of capital deployed to CFS reflects investor confidence in tokamak-based fusion as a near-term path to commercial viability in a sector historically dominated by government-funded research.
cfs.energy ↗·Fusion Energy·USA·private 
