Commonwealth Fusion Systems Becomes First Fusion Company to Apply to PJM Interconnection, the Largest U.S. Wholesale Electricity Market

• The application marks the first time a fusion power plant developer has requested to join a major grid operator. Through this submission, CFS is demonstrating the ability to connect a fusion power plant to a system that serves about 182,000 megawatts (MW) of capacity to more than 65 million customers.
• Submitting this interconnection request helps to derisk delivering power from the ARC plant since it is one of the long-lead actions necessary to connect a grid-scale power plant in the early 2030s. As part of the submission procedure, CFS will work through PJM's diligent stress-test process to demonstrate that it can reliably help to meet the region's surging energy demands.
• CFS' power plant will be located in the heart of Virginia, the region with the highest forecasted load growth in the U.S. By entering PJM's queue now, CFS will ensure that it will be able to connect to the grid upon completion of the power plant's construction.

DEVENS, Mass., April 28, 2026 /PRNewswire/ -- Commonwealth Fusion Systems (CFS), the world's largest and leading private fusion company, announced today that it is the first fusion power plant developer to apply to connect to a major grid. This crucial step bridges the science and technology of fusion energy with the real-world infrastructure that will actually deliver it.

CFS submitted an application to connect its first ARC fusion power plant to PJM Interconnection, the largest U.S. competitive wholesale electricity market, serving about 182,000 megawatts (MW) of capacity across 13 states and the District of Columbia to more than 65 million customers. The application is the first-ever request from a grid-scale fusion power plant developer to a major regional transmission organization.

In order to submit this application, CFS had to have a clear understanding of not just the fusion part of the ARC power plant, but the power delivery portion of that plant, including a deep understanding of all the power delivery subsystems. Dominion Energy advised CFS on best practices for navigating PJM's interconnection process as part of its Joint Development Agreement with CFS.

"Our commitment to delivering the benefits of fusion, and enabling a future with abundant, secure energy, means that we're not just proving fusion physics works — we're showing exactly how fusion power plant watts get from our machine to the customer, working with the grid and a utility," said Bob Mumgaard, Co-Founder and CEO of CFS. "By becoming the first fusion energy developer to enter a major grid operator's interconnection queue, we're demonstrating that when you're serious about building a power plant in the early 2030s, you act now. This is execution."

Regional transmission organizations (RTOs) manage much of the bulk electrical grid in the U.S., and PJM is the largest. These RTOs ensure that there are functioning competitive electricity wholesale markets as well as regional reliability. They synchronize the complex web of generators and transmission lines, helping to match power supply and demand on a second-by-second basis. By accommodating these changing power needs, this system helps to avoid power outages and keeps the grid running for all its industrial, commercial, and residential users.

An interconnection application is the formal process of requesting to "plug in" a new power plant to one of these RTOs; it kicks off a series of deep engineering studies to ensure the grid can safely and reliably handle the influx of the new generating capacity and energy being provided and assess whether any network upgrades are required.

Navigating grid interconnection is a complex process, and it involves more than a conceptual design. Submitting the interconnection request is one of the long-lead actions necessary for providing power in the early 2030s because the start of the study process to the generation of electricity can take four to six years. In the case of PJM, the operator will use sophisticated grid simulation models to diligently stress-test the generation systems of CFS' fusion power plant to ensure it can connect reliably to help meet the region's surging energy demands.

The application keeps CFS on track to connect its first power plant to the grid and deliver electricity in the early 2030s. The move follows the successful navigation of several pre-construction milestones in 2025, which includes securing the world's first Conditional Use Permit for a commercial fusion power plant and signing offtake agreements with two customers, Google and Eni, as part of long-term strategic partnerships with each company.

CFS also announced that the site in Chesterfield County, Virginia, on which its first 400-megawatt ARC power plant will be built, has been named the Fall Line Fusion Power Station. The name references the geological boundary where Virginia's elevated Piedmont region drops down to the Tidewater coastal plain, creating the rapids on the James River. Historically, Virginians built mills at the Fall Line to harness the power of falling water. Today, CFS will harness a different energy source: the clean, safe, secure power of fusion.

About Commonwealth Fusion Systems

Commonwealth Fusion Systems is the world's largest and leading private fusion company. The company's marquee fusion project, SPARC, will generate net energy, paving the way for limitless carbon-free energy. The company has raised almost $3 billion in capital since it was founded in 2018. SPARC® and ARC™ are trademarks of Commonwealth Fusion Systems®.

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SOURCE Commonwealth Fusion Systems