**This project is at the University of Bristol**
Commercial fusion energy is transitioning from experimental facilities to power plants by the 2030s and 2040s, creating an unprecedented challenge at the intersection of energy security and nuclear non-proliferation. This doctoral research addresses a critical regulatory gap: how to safely and securely transport 100+ kilograms of tritium annually across international borders while preventing weapons proliferation. Tritium, the essential fuel for fusion reactors, is also a potent weapons material. Yet, current international safeguards explicitly exclude it and were designed for research-scale operations measured in grams, not the commercial-scale flows measured in kilograms that fusion power plants will require.
For example, the UK's Spherical Tokamak for Energy Production (STEP) program aims to deliver a prototype fusion power plant by 2040, requiring 10-20 kg of tritium for initial commissioning and periodic replenishment from Canadian suppliers. However, no legal framework exists for fusion-scale tritium transport, measurement uncertainties of 2-10% are acknowledged as inadequate for detecting diversion, and export controls lack verification mechanisms for end-use compliance. The global tritium supply chain faces a crisis as Canadian CANDU reactor production declines from approximately 2 kg annually to near-zero by the late 2030s, just as commercial reactors begin operation. This perfect storm of supply scarcity, regulatory gaps, and proliferation risk threatens to derail the commercialisation of fusion unless comprehensive safeguards frameworks are developed now, before industry practices become entrenched.
This PhD will develop the first comprehensive technical-policy framework for secure large-scale tritium transport, integrating five innovations. First, you will establish material accountancy algorithms using Monte Carlo simulation and Bayesian inference to distinguish normal tritium losses from suspicious discrepancies during transport, and to develop statistical thresholds that balance detection probability and false alarm rates. Second, you will design a cyber-physical verification system that incorporates real-time sensors, an encrypted blockchain for chain-of-custody records, and remote monitoring protocols to enable regulatory oversight without compromising operational efficiency. Third, you will conduct a systematic regulatory gap analysis across IAEA safeguards, Nuclear Suppliers Group guidelines, and national frameworks, benchmarking tritium controls against the effectiveness of uranium and plutonium safeguards. Fourth, you will develop an international governance framework, including draft amendments to IAEA safeguards agreements and bilateral treaty templates for tritium transport. Finally, you will validate the entire framework through a detailed UK STEP case study modelling quarterly shipments from Canada to Culham across multiple scenarios.
What We're Looking For
The ideal candidate has a strong background in nuclear engineering, physics, or a related quantitative discipline, combined with a genuine interest in policy, security studies, and international governance. Essential skills include solid computational abilities in Python or MATLAB for developing material accountancy algorithms and running Monte Carlo simulations, along with excellent written and oral communication for engaging diverse stakeholders from technical experts to policymakers. Desirable but not required attributes include prior exposure to nuclear safeguards, export controls, or fusion technology through coursework or internships; eligibility for a security clearance, which would facilitate access to specific operational details; and existing connections to UKAEA, the IAEA, or the fusion industry. Most critically, we seek someone with intellectual curiosity spanning disciplines, comfort working at the technical-policy interface, and a commitment to producing research with real-world impact beyond academic citations. This project is not for those seeking pure laboratory work or purely theoretical study, but rather for candidates who want to tackle urgent applied challenges where technical innovation and policy development must advance in tandem.
How to apply: please specify that the project is withiin the Fusion Engineering CDT and apply though this link https://www.bristol.ac.uk/study/postgraduate/apply/
Funding notes
This project is part-funded by a Community Studentship provided by the Fusion Engineering CDT, and hence the student will be based at the University of Bristol, but should expect to engage fully with the 3-month full-time training programme in the Fusion Engineering CDT at the start of the course (October to December inclusive). CDT training will be delivered across the CDT partner universities at Sheffield, Manchester, Birmingham and Liverpool. The training course requires weekly travel to attend in-person training at these universities. For further information about the CDT programme, please visit the CDT website at www.fusion-engineering-cdt.ac.uk or send an email to hello@fusion-engineering-cdt.ac.uk.
What are the candidate requirements?
PhD applicants must hold/achieve a minimum of a merit at master's degree level (or international equivalent) in a relevant discipline. Applicants without a master's qualification may be considered on an exceptional basis, provided they hold a first class undergraduate degree. Please note, acceptance will also depend on readiness to pursue a research degree.
https://www.bristol.ac.uk/study/postgraduate/research/mechanical-engineering/#entry-requirements
English language requirements
If English is not your first language, you will need to reach the requirements outlined in our profile level E. https://www.bristol.ac.uk/study/language-requirements/profile-e/
fusion_cdt