Commonwealth Fusion Systems

Senior Process Engineer

Join Commonwealth Fusion Systems in Devens, Massachusetts as a Senior Process Engineer. Lead helium cryogenics plant commissioning and operations, ensuring safety and performance. Enjoy competitive pay, equity, flexible vacation, and health benefits while advancing fusion energy technology.
Commonwealth Fusion Systems
Commonwealth Fusion Systems
Devens, Massachusetts, United States On-site Full time USD 110k–185k yearly UTC-05:00

Commonwealth Fusion Systems

Company Overview

Commonwealth Fusion Systems (CFS)

Cambridge, MA, United States

2018

Approximately 430 employees (source: zoominfo.com). Revenue figures vary, with reports indicating $211.3 million or $31.7 million, though as a pre-revenue fusion developer focused on R&D, these may reflect funding or operations rather than sales.

What They Do

Commonwealth Fusion Systems (CFS) is a pioneering private fusion energy company that specializes in tokamak-based magnetic confinement fusion. Founded as a spinout from MIT's Plasma Science and Fusion Center, CFS focuses on utilizing high-temperature superconducting magnets to achieve commercial net energy production (source: cfs.energy). The company has made significant strides in its technology, particularly with the development of compact fusion machines that leverage decades of tokamak science. Their flagship projects, SPARC and ARC, aim to demonstrate net energy gain and commercial viability in the coming years (source: cfs.energy).

Projects & Track Record

CFS is currently engaged in several groundbreaking projects, most notably the construction of SPARC, which is set to be the world's first net-energy fusion machine. Located at their Fusion Energy Campus in Devens, Massachusetts, SPARC aims to demonstrate net energy gain by the late 2020s (source: cfs.energy). Additionally, CFS is planning the ARC project, a 400 MW-class grid-scale tokamak power plant designed for commercial deployment in the early 2030s. These projects are underpinned by significant technological advancements, including the successful testing of the central solenoid magnet module (CSMC) in November 2024, which confirmed the manufacturability of critical components for SPARC (source: zoominfo.com).

Recent Developments

In the past two years, CFS has made remarkable progress, including the opening of its Devens Fusion Energy Campus on February 10, 2023, which was attended by notable figures such as U.S. Secretary of Energy Jennifer Granholm (source: cfs.energy). The company has also secured substantial funding, raising $863 million in August 2024, building on a previous $1.8 billion round in May 2023, bringing total funding to over $2 billion (source: wbjournal.com). Furthermore, CFS announced its first commercial power plant site in Chesterfield County, Virginia, which will be independently financed and operated, with plans for grid connection in the early 2030s (source: zoominfo.com).

Working There

CFS offers a range of roles across various disciplines, including fusion science, engineering, manufacturing, and materials science. The majority of their workforce is based at the Devens campus, which has grown to over 430 employees (source: cfs.energy). The company culture emphasizes rapid execution and transparency, attracting top talent from the fusion and manufacturing sectors. Key executives include Co-Founder and CEO Bob Mumgaard, along with other leaders in operations and science, indicating a strong demand for expertise in tough tech and physics (source: nasdaqprivatemarket.com). While specific benefits are not detailed, the scale-up and investor backing suggest competitive packages for high-caliber roles in a mission-driven environment (source: cfs.energy). Job seekers are encouraged to monitor their careers page for openings related to SPARC and ARC advancements.


Last updated on Feb 23, 2026 | Report an issue

Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy.

Combining decades of research, top talent, and new technologies, we're designing and building commercially viable fusion power plants. And we're working with policymakers and suppliers to build the energy industry of the future.

We're in the best position to make it happen. Since 2018, we've raised nearly $3 billion in capital, making us the largest and leading private fusion company in the world.

Now we're looking for more thinkers, doers, builders, and makers to join us. People who'll bring new perspectives, solve tough problems, and thrive as part of a team.

If that's you and this role fits, we want to hear from you.

Join the power movement as a Senior Process Engineer

The SPARC Cryoplant (CRYP) team is responsible to deliver a large-scale helium cryogenics plant system on-time, on-budget, and meeting technical and performance requirements. The team is currently executing a fast-tracked install and commissioning to validate SPARC requirements prior to hand-off to Operations. Major equipment includes: 4 MW of compressor power, 500 m3 of helium gas storage, purification and oil removal systems, a 18-m cryogenic refrigeration coldbox with control valves, heat exchangers, pressure vessels, and turbomachinery, and a distributed control system. The team is looking for an experienced process engineer to support plant operations through commissioning, develop process safety and controls, and finalize process design documentation. Following commissioning and hand-off to Operations, the CRYP Process Engineer will transition to support development of future process system projects, including the ARC plant. Among other things, the Cryogenics team values: responsibility, proactiveness, prioritization, planning, critical thinking, a sense of urgency, growth mindset, accountability, communication, and collaboration.

What you'll do

  • Learn the CRYO system ins-and-outs and become a SME for commissioning and operations
  • Perform thermal fluid system process design and analysis
  • Support plant operations through commissioning, including occasional shift work
  • Create 2D/3D design drawings and process schematics
  • Create valve, instrument, machinery, and equipment lists
  • Troubleshoot machinery, equipment, instrumentation, and controls
  • Develop CONOPs and HMIs for software and controls implementation
  • Prepare and execute operating, maintenance, and repair plans and procedures
  • Write specifications, RFIs/RFQs/RFPs, and manage procurements and build-outs
  • Develop interface and performance requirements and hardware specifications and selection
  • Design and fabricate hardware and equipment skids
  • Plan acceptance and performance tests and quality inspections
  • Coordinate contractor daily activities in the field and factory

What we're looking for

  • Bachelor of Science in Mechanical, Chemical, or Process Engineering
  • Fluid system process engineering design
  • Hands-on commissioning / operation of mechanical / fluid systems
  • Thermal fluid system process, equipment, and component design
  • Compressible fluid hydraulic, heat and mass transfer, and pressure safety analysis
  • Specification and selection of mechanical and controls hardware
  • Procurement and vendor management
  • Safety hazards and PPE requirements for plant operations
  • Familiarity around pressurized systems, cryogenic fluids, and rotating machinery
  • Familiarity with electrical and controls diagnostic tools, including multimeter and HART communicator
  • Familiarity with precision tooling, alignments, torque specifications, welding specifications
  • Familiarity with ASME, ANSI, CGA, NFPA, IEEE, OSHA codes and standards

Bonus points for

  • Specify, design, install, commission large-scale fluid cryogenic systems
  • Hands-on operation of compressible fluid systems with pressure vessels, process piping, pumps, valves, compressors, heat exchangers
  • Design, install, commission industrial-scale rotating machinery, e.g. compressors, pumps, and turbines
  • Repair and maintenance of industrial-scale process piping, pressure vessels, valves, and filtration systems.
  • Create and release CAD drawings for fabrication
  • Project management, including in a matrixed organization

Must-have requirements

  • Ability to lift up to 50 lbs occasionally
  • Perform activities such as stooping, climbing, typing, standing and sitting for extended periods of time
  • Willingness to occasionally travel or work required nights/weekends/on-call; potential occasional travel to suppliers or contractors
  • Dedication to safety to mitigate hazards that may include heat, cold, noise, fumes, strong magnets, lead, high voltage, and cryogenics

$110,000 - $185,000 a year

Salary range for this full-time position + equity + benefits. The actual salary will depend on level, location, qualifications, and experience. The range displayed on each job posting reflects new hire salaries for the position across all US locations. Benefits include:

  • Competitive compensation with equity
  • 13 Company-wide Holidays
  • Flexible vacation days
  • 10 sick days
  • Generous parental leave policy
  • Health, dental, and vision insurance
  • 401(k) with employer matching
  • Professional growth opportunities
  • Team-building activities

At CFS, we excel in fast-paced environments, driven by our values of integrity, execution, impact, and self-critique. As we grow, we're eager to bring on mission-driven folks who offer diverse perspectives and fresh ways to tackle challenges.

We value diversity deeply and are proud to be an equal opportunity employer by choice. We consider all qualified applicants equally, regardless of race, color, national origin, ancestry, citizenship status, protected veteran status, religion, physical or mental disability, marital status, sex, sexual orientation, gender identity or expression, age, or any other basis protected by law.

This role requires compliance with U.S. laws concerning the export of controlled or protected technologies or information (collectively, "Export Control Laws"). Any offer of employment will be contingent on the need for compliance with such Export Control Laws.

Apply now

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About the role

June 11, 2026

Full time

Company

June 12, 2026

On-site

USD 110k–185k yearly

Hydrogen

Commonwealth Fusion Systems

cfs.energy

  •  Devens, Massachusetts, United States

Experienced

UTC-05:00