How does a breeder blanket work?
PURPOSE: A breeder blanket is used in fusion energy machines to produce more fuel whilst also acting as a heat exchange, which can later be used to generate electricityThe aim is to produce tritium, the extremely rare fusion fuel, by embedding lithium in the blanket. TheLithium will react with neutrons to produce the required tritium.
POSITION: The breeder blanket surrounds the fusion machines’ core where the fusion events happen.
FUSION: Fusion combines small atoms to make larger atoms (such as helium), releasing a lot of energy.
FUEL PRODUCTION: The breeder blanket contains materials (such as lithium) that absorb the high-energy particles (neutrons) released during the fusion events.
NEUTRON ABSORPTION: When these neutrons hit the lithium in the blanket, they transform it into another fuel called tritium, which can then be used in future fusion events.
HEAT ABSORPTION: The breeder blanket also absorbs the heat generated from the fusion events.
RADIATION SHIELDING: To maintain the integrity of machine components.
ENERGY CONVERSION: This heat can be used to produce steam, which drives turbines to generate electricity.
DUAL ROLE: So, the breeder blanket helps by both creating more fuel and exchanging the heat released during fusion. This way, the breeder blanket plays a crucial role in making fusion energy a more sustainable and efficient energy source.
Timeframe and Key Milestones
| Tranche | Year | Milestone |
| Outline Business Case approved – Tranche 1
(24/25-25/26) |
Jun-24 | Commercial Assurance Board (CAB) approval to start Neutron Source Procurement (invitation to tender process) |
| Aug-24 | Downselect Culham Campus building site for LIBRTI Facility (and trigger RIBA 3 activity) | |
| Oct-24 | First competitive research award for breeder experiments (re-issued call) | |
| Dec-24 | Contract Award Neutron Source | |
| Dec-24 | Agree Heads of Terms (understanding of a way to play) for first international multilateral consortium for a Breeder Mock-up Experiment | |
| Apr-25 | to tender issue for Building | |
| H1-2025 | Initiate an engineering and digital framework for industry engagement in LIBRTI | |
| H2-2025 | Award procurement contract for Building | |
| Aug-25 | Earliest opportunity to finalise Tranche 2 business case to release LIBRTI final two years of programme funding |
How does the programme fit into Fusion Futures, UKAEA, and under DESNZ?
Fusion Futures is a wide-ranging grant platform to enable the local fusion community (national lab, industry, academia) to fully engage in capability building and economic engagement with fusion in Europe and globally. LIBRTI is one of three core elements of this endeavour to increase capability and engagement across the sector.
The launch of LIBRTI demonstrates progress on the Government’s UK Fusion Strategy, which outlines the requirement for this programme: “The UK plans to build a fusion fuel cycle facility partnering with academia and industry to solve one of the biggest challenges of commercialising fusion.” This demonstrates the UK Government’s appreciation that the fusion fuel cycle is a critical technology that needs de-risking to achieve commercialisation.
LIBRTI also builds on the Government’s international fusion partnerships, such as the recently announced UK and US partnership.
Programme Objectives
The programme aims to:
- Design, implement and validate innovative tritium breeder technologies by developing a first of a kind, world leading, facility that exposes engineered breeder prototypes to high flux fusion neutrons, and to capture the knowledge gained from these experiments.
- Establish a digital simulation capability and skills to model breeder technologies, predict tritium breeding performance, analyse experimental results and provide guidance for future design development of breeder blankets ideas.
- Develop collaborative partnerships with greater than half of the LIBRTI funding being invested and leveraged in industry and academia.
- Maximise industrial growth in fusion fuel technologies and spillover into adjacent sectors to enable UK industry to export the technology globally.
- Drive inward investment through further development of the UK Fusion Cluster.
- Expand key UK skills through design, build and operation of a first of a kind facility, including within the supply chain.
Programme Deliverables
The LIBRTI team is focussed on delivering:
- A significantly repurposed Culham Site building to house a commercially available 14 MeV neutron source, shielding and thermal management installations for breeder experiments and space for pre- and post-experiment activities (including cool down and disassembly of activated materials)
- A flexible and scalable digital platform that enables full in silico replication of breeding experiments for breeding model validation and improved breeder test methodologies via simulation
- A cohort of expertise within both UK and international partners, which can provide scientific, engineering, operational and programme management capabilities to underpin ongoing breeder developments and wider UK Fusion Cluster activities
- A research path to a higher neutron flux on the installed source via retrofits or aggregation of units
- Facilitation of, and participation in, early international ‘user consortia’ to ensure that the physical installation delivers a testbed that is fit-for-purpose and that early experiments operate within safety and environmental boundary conditions
- Increased enablement of industry and academia to use LIBRTI, via a steady investment in feederstream research
Identified Benefits of the Programme
- Demonstrate considerable technical risk reduction for fusion fuel cycle technologies
- Demonstrate to regulators that fusion fuel inventory control in an integrated fuel cycle element
- Maintain UK international leadership in Fusion Research
- Enhance international supply chain capability and capacity in fusion fuel technologies
- Develop commercialisable Intellectual Property for the UK and its international partners
- Increase income for UK industry
- Increase efficiencies and investor confidence in fusion technology firms
- Increase human capital though growth of fusion skills workforce in the UK
How external parties can get involved
- In the first quarter of 2024, LIBRTI issued a combined Request for Information – Prior Information Notice to canvas potential users, suppliers and collaborators on their thoughts.
- The response was encouraging and allowed the Programme to launch an invitation to tender for its Neutron Source and a series of convened workshops to facilitate early future user group discussions
- Over the next 2 months, LIBRTI will announce the outcome of its neutron source procurement.
- Over the next 6 months, LIBRTI will engage the market to create an engineering and digital framework to harness Tier 1 capabilities for the LIBRTI physical and digital builds.
- Over the next 12-18 months, LIBRTI will launch a series of feederstream R&D project calls (likely to address, but not limited to, shielding, control and instrumentation, diagnostics development, digital platform development, ventilation etc.) Participation in a mini breeder or large mock up experiment will not preclude parties from feederstream projects and funding.
- All procurement opportunities will appear on our UKAEA pipeline and for any enquiries please reach out to our Commercial Lead for the programme.
