Senior Process Engineer

About Commonwealth Fusion Systems:

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, suppliers, and many others to build the energy industry of the future.

We’re in the best position to make it happen. Since 2018, we’ve raised $4 billion of capital, making us the largest and leading 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

CFS is looking for a Senior Process Engineer with deep chemical engineering fundamentals and experience designing, scaling up, commissioning, and operating process systems in large industrial facilities.

The ideal candidate comes from an industry such as power generation, petrochemical processing, liquefied natural gas (LNG), industrial gases, chemicals, air separation, cryogenic refrigeration, pulp & paper, or another large-scale process industry. You understand how to translate fundamental process requirements into practical industrial systems and have taken designs from early concepts through Front-End Loading (FEL), detailed engineering, construction, commissioning, start-up, and operation.

Fusion power plants bring together process technologies that traditionally span multiple industries. At CFS, you will have the opportunity to work across cryogenic systems including helium and nitrogen, power generation and steam systems, molten salt systems, fueling and gas processing, vacuum systems, and process utilities such as cooling water and instrument air.

We are looking for an engineer who understands how these systems behave in the real world because they have personally designed, built, commissioned, operated, or troubleshot industrial process equipment. You should be equally comfortable developing a process design basis, building a heat and material balance, sizing equipment, originating and owning P&IDs, leading a HAZOP, walking down installed piping, supporting start-up, and diagnosing why an operating system is not performing as designed.

What you'll do:

• Own process engineering scope for complex systems from early concept through design, construction, commissioning, start-up, and operation
• Develop process concepts and translate fundamental engineering requirements into practical, commercially viable industrial systems
• Develop process design bases, operating envelopes, design cases, process flow diagrams (PFDs), heat and material balances, utility balances, P&IDs, equipment lists, line lists, and process datasheets
• Apply chemical engineering fundamentals including thermodynamics, phase equilibrium, fluid mechanics, heat and mass transfer, transport phenomena, reaction engineering, separations, process dynamics, and process control
• Develop steady-state and dynamic process models and use engineering analysis to guide system architecture, equipment selection, and operating strategy
• Size and specify process equipment including pumps, compressors, blowers, heat exchangers, vessels, columns, piping systems, control valves, relief devices, and other unit operations
• Lead process engineering through Front-End Loading (FEL) and progressively mature systems from conceptual design through process definition and engineering definition
• Evaluate process alternatives and technical tradeoffs considering performance, safety, reliability, operability, maintainability, capital cost, and lifecycle cost
• Develop equipment and package specifications, technically evaluate vendor proposals, and work directly with equipment suppliers and fabricators
• Lead or contribute to process safety activities including HAZOPs, design reviews, relief and depressurization studies, consequence evaluations, and development of safeguards
• Develop process control philosophies, operating sequences, alarm requirements, permissives, interlocks, and operating limits in collaboration with controls engineers and operators
• Perform multidisciplinary technical reviews to ensure that systems are safe, operable, maintainable, and capable of achieving their intended process function
• Support procurement, fabrication, construction, installation, inspection, and field engineering, including field walkdowns and resolution of design and construction issues
• Develop commissioning plans, test procedures, operating procedures, and start-up strategies and participate directly in commissioning, start-up, performance testing, and operation of process systems
• Troubleshoot operating equipment and processes using first-principles engineering, process data, field observations, and structured process investigations
• Capture lessons learned from construction, commissioning, and operation and translate them into improvements in process safety, reliability, operability, maintainability, performance, engineering standards, and future designs
• Provide technical leadership and mentor less‑experienced engineers on complex process engineering problems

What we're looking for:

• Bachelor’s degree in Chemical Engineering (or closely related discipline)
• 7+ years of relevant industrial process engineering experience, or equivalent demonstrated depth of experience
• Strong command of chemical engineering fundamentals including mass and energy balances, thermodynamics, phase equilibrium, fluid mechanics, heat and mass transfer, transport phenomena, unit operations, and process dynamics and control
• Experience designing process systems for large-scale industrial facilities
• Demonstrated experience taking process systems through a structured FEL or equivalent stage-gated project development process, from concept and process definition through detailed engineering and execution
• Experience with process scale-up, technology scale-up, or translating process requirements into commercial-scale equipment and facilities
• Demonstrated experience developing core process engineering deliverables including process design bases, heat and material balances, PFDs, P&IDs, equipment specifications, datasheets, and process calculations
• Experience sizing, specifying, and selecting industrial process equipment
• Hands‑on experience operating, commissioning, starting up, performance testing, and troubleshooting industrial process systems and physical equipment
• Experience working directly with operators and technicians and using operating data and field observations to diagnose process performance
• Experience with process simulation and analysis tools such as EcoSim, Aspen HYSYS, Aspen Plus, AVEVA Process Simulation, or equivalent
• Experience with process safety and hazard analysis, including HAZOP or equivalent methodologies
• Experience with relief system design and overpressure protection
• Experience working with and integrating other engineering disciplines including mechanical, piping, instrumentation and controls, electrical, safety, operations, and construction
• Experience working directly with equipment vendors, fabricators, EPC organizations, or construction contractors
• Familiarity with applicable process industry codes and standards, including ASME B31.3 and ASME BPVC Section VIII
• Ability to clearly express and critique technical ideas, assumptions, risks, and tradeoffs
• Strong engineering judgment and the ability to recognize when analytical or simulation results do not make physical sense
• Attention to detail with an emphasis on practical, elegant, and commercially viable engineering solutions
• Values that align with our company’s values of integrity, execution, impact, and self‑critique

Bonus points for:

• Experience designing, commissioning, or operating large-scale cryogenic systems, particularly helium systems
• Experience in power generation, petrochemical, LNG, industrial gases, chemical processing, nuclear, or other large-scale process facilities
• Experience with steam systems, particularly steam generation, steam distribution, condensate, and balance‑of‑plant systems
• Experience designing, commissioning, or operating molten salt systems
• Experience designing, commissioning, or operating industrial vacuum or high‑vacuum systems
• Experience with industrial gas processing, purification, separation, or fueling systems
• Experience with large-scale process utilities including cooling water, chilled water, compressed or instrument air, nitrogen, and other plant utility systems
• Experience scaling first‑of‑a‑kind technologies from pilot or demonstration scale to commercial operation
• Experience with dynamic process simulation and control‑system development
• Experience with industrial automation
• Licensed as a Professional Engineer

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, including occasional travel to suppliers, contractors, or operating facilities
• Willingness and ability to work hands‑on in industrial, construction, commissioning, and operating environments
• Dedication to safety to mitigate hazards that may include heat, cold, noise, fumes, strong magnets, lead, high voltage, high current, pressure systems, vacuum systems, hazardous materials, and cryogenics

Salary range for this full-time position + equity + benefits

• 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

$110,000 - $185,000 a year

#LI-Onsite

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.