Commonwealth Fusion Systems (CFS), a Massachusetts-based company spun out of MIT, has secured $863 million in new financing to accelerate its push toward making fusion energy a commercial reality. The latest funding round brings the company’s total investment close to $3 billion, underscoring how private capital is increasingly betting on fusion as the next frontier in clean power.

Tech Giants Step In

Among the new backers are Nvidia, through its NVentures arm, and Google, which has already deepened its role by signing a deal to purchase 200 megawatts of future fusion electricity. The round also drew support from Japanese conglomerates, major hedge funds, and energy investors, joining existing stakeholders such as Breakthrough Energy Ventures and Italian energy company Eni.

For Nvidia and Google, the move is strategic. Both companies run energy-hungry data centers to power artificial intelligence and cloud services, and fusion could one day provide a stable, carbon-free power source to sustain that growth.

Building the Future of Fusion

CFS plans to use the funds to complete its SPARC reactor, currently being built in Devens, Massachusetts. The demonstration machine is expected to start operations in 2026 and could prove whether a compact fusion reactor can generate more energy than it consumes by 2027.

If successful, the company’s next step will be ARC, a commercial-scale fusion plant designed to deliver around 400 megawatts of electricity. The first ARC facility is planned for Virginia, with operations aimed for the early 2030s.

A Big Bet With Big Risks

Fusion power has long been described as the “holy grail” of clean energy because it mimics the reactions that fuel the sun—without producing long-lived radioactive waste or greenhouse gases. However, despite decades of research, no group has yet proven it can generate fusion energy at a commercial scale.

Sceptics caution that even with billions in private funding, scaling the technology will require solving complex physics and engineering hurdles. Some experts believe commercially viable fusion may not arrive until mid-century.

Why It Matters

Still, the heavy involvement of Nvidia, Google, and global financiers signals that momentum is shifting. As artificial intelligence drives electricity demand higher, the search for abundant, reliable, carbon-free power is intensifying. If CFS can deliver on its promises, fusion could not only transform the energy mix but also provide the backbone for the world’s growing digital infrastructure.