Senior Neutronics Engineer

Number of employees

220

Abingdon, United Kingdom

Posted on: 2025-11-21

Category: renewables

Apply now

Please let Tokamak Energy know you found this job on Work in Green. This will help us grow!

Employment type:

Full time

Experience required:

Senior

Salary

Salary not provided

About the company:

The world needs a clean and reliable source of base-load energy to develop sustainably into the future. That’s what Tokamak Energy is striving to achieve.

Tokamak Energy is a private company accelerating the development of fusion power.

Fusion – the energy source that powers the sun – is globally accepted as the best way to generate plentiful, safe, secure and clean energy. The tokamak is the most heavily researched and best understood of all the different paths to fusion.

It is now acknowledged that the spherical tokamak design offers the smallest and most cost-effective solution. This is our solution. Yet there are many complex engineering challenges that need to be overcome for demonstration and commercialisation of this technology.

Our team of world-class fusion scientists and magnet engineers is tackling these challenges to develop efficient and affordable fusion power. Our unique approach is centred on rapid innovation using the latest materials and technology – but building on decades of scientific research and experience. This strategy gives us – and the world – a faster way to fusion.

Once fusion electricity is achieved, our scalable technology could be rolled out across the world as a solution to one of humanity’s greatest challenges: clean and sustainable energy for all.

Working arrangements

Please note this role does offer hybrid working, our model sets out a minimum 60% onsite / 40% home working split

Part time working or job share options will be reviewed on an individual basis.

Overview of the role

Fusion energy requires that a number of fascinating design challenges are met. One of these is nuclear technologies; focusing on shielding, tritium breeding, material assessments and activation. We are looking for a senior engineer to lead the technical focus in solving some of these challenges by applying sound physics and engineering judgement to develop solutions which meet the design requirements.

 

In this role, you will:

  • Work within the Plant Prediction and Simulation department, playing a key role in the development of 3D radiation transport models of prototype fusion energy devices and other radiation sources
  • Lead the neutronics effort to progress the design of power plant concepts, including radiation shielding, breeder blanket and bioshield technology, within an integrated project team
  • Advance the maturity of shielding, breeder blanket and bioshield design solutions from initial conceptualisation through to detailed design
  • Support subject matter experts in Radiation Measurement and Dosimetry
  • Supervise the characterisation of the ionising radiation environment (including heat, biological and absorbed dose, and differential fluence) within and around fusion-energy devices or other radiation sources
  • Support the development of radiation transport/radiation effects tools to enhance the efficiency of design workflows
  • Propose and perform validation and verification activities on radiation transport models
  • Present technical information on the radiation environment, its effects, and the performance of shielding and breeder blankets to both expert and non-expert audiences
  • Interface and collaborate with a variety of in-house and external resources

Requirements

  • Expertise in radiation transport code such as MCNP, OpenMC or GEANT4, with experience mentoring and guiding teams in advanced applications.
  • Expertise in activation/transmutation codes, primarily FISPACT-II, with knowledge of ORIGEN or similar tools and their strategic deployment in research and industry applications.
  • Experience in or knowledge of nuclear fusion technology, including in tokamak design principles and contributions to high-impact projects.
  • Strategic knowledge of assurance techniques for radiation modelling results, with a proven ability to lead computational and experimental validation efforts.
  • Good communication skills, capable of engaging with executive leadership, stakeholders, and external partners, while effectively supporting and guiding technical teams.
  • Demonstrated technical leadership in solving complex problems through rigorous methodologies, fostering a culture of high-quality planning, execution, and review.
  • Advanced computational proficiency, ensuring optimal use of radiation transport software, including implementation of variance reduction techniques and streamlined analytical reporting through specialised software tools.
  • Proactive leadership, driving projects to success under challenging objectives and compressed timelines, with an ability to set and refine strategic directions.
  • Self-driven and visionary approach, able to independently make decisions while also fostering collaboration across multidisciplinary teams.
  • Experience in leading teams of scientists and engineers, with a track record of mentoring, developing talent, and driving collective success.

Benefits

Benefits

  • 25 days holiday (plus bank holidays and 3 festive days to be used between Christmas and the New Year)
  • Company pension scheme
  • Eligible for company share option scheme
  • Company bonus scheme, discretionary, dependant on performance
  • A range of financial benefits including death in service and critical illness cover
  • Cycle to work scheme

Hazard-specific / Safety-critical duties

This job includes the following hazards or safety-critical activities which will require successful pre-employment health screening through our occupational health service before the successful candidate will be allowed to start work:

  • Working at height (ladders, scissor lifts, cherry pickers & scaffolding)
  • Night working (11pm-6am)
  • Work in hot or cold environments
  • Driving on Company business
  • Working with ionising radiation
  • Work with cryogenic fluids including liquid nitrogen
  • Working with or in the vicinity of equipment that produces high magnetic fields
  • Working with materials that are managed under the control of substances hazardous to health regulations (COSHH)
  • Travel outside of Europe or North America on company business

About Us

What if there was a limitless, safe, clean, low-cost energy source, providing much needed global energy security? What if that energy source could also help reduce climate change? We believe that’s fusion energy. Tokamak Energy is a leading global commercial fusion energy company based near Oxford, UK. We have an unrivalled track record designing and operating spherical tokamaks; the optimal route to commercial fusion energy.

In addition to fusion energy, Tokamak Energy is recognised as the leader in High Temperature Superconductor (HTS) magnet, design, numerical modelling, and prototyping. Our dedicated HTS magnet team, in collaboration with key manufacturing partners, is focussed on becoming the leading supplier of HTS magnets to multiple markets.

The company, founded in 2009 as a spin-off from the UK’s Culham Centre for Fusion Energy, currently employs a growing team of over 250 people with experts from the UK and around the world. It combines world leading scientific, engineering, industrial and commercial capabilities. The company has 70 families of patent applications and has raised $250 million, comprising $200m from private investors and $50m from the UK and US governments. Our US subsidiary, Tokamak Energy Inc, was established in 2019.

Come and be a part of a dynamic and innovative team who are striving to provide a solution to one of humanity’s greatest challenges: clean and sustainable energy for all.

Important information

Please note that any personal data submitted to Tokamak Energy will be processed in accordance with the GDPR and related UK data protection legislation.

If you do not meet all the listed criteria for this position, we would still welcome your application.

Entry into employment with Tokamak Energy and progression within employment will be determined only by personal merit and the application of criteria which are related to the duties of each post and the relevant salary structure. In all cases, ability to perform the job will be the primary consideration.

No applicant or member of staff shall be discriminated against because of age, disability, gender reassignment, marriage or civil partnership, pregnancy or maternity, race, religion or belief, sex, or sexual orientation.

Similar climate jobs

These are some of our top picks for great climate jobs on Work in Green.

View all jobs
Tokamak Energy logo
United Kingdom
Tokamak Energy logo
United Kingdom
Number of employees

220

Full time
Renewables
Form Energy logo
United States
Number of employees

840

Dollar sign

$128,670.00 - $167,970.00

Full time
Renewables
Helion logo
United States
Helion logo
United States
Number of employees

340

Full time
Renewables
Commonwealth Fusion Systems logo
United States

250 Renewables jobs at Tokamak Energy

Tokamak Energy is hiring Senior Neutronics Engineer,IP Manager,Neutronics & Fluid Dynamics Team Leader, and more.

View all jobs at Tokamak Energy
Tokamak Energy logo
United Kingdom
Tokamak Energy logo
United Kingdom
Number of employees

220

Full time
Renewables
Tokamak Energy logo
United Kingdom
Tokamak Energy logo
United Kingdom
Tokamak Energy logo
United Kingdom
Tokamak Energy logo
United Kingdom