Great British Energy Just Awarded a £360M SMR Contract. Here Is What Nuclear Infrastructure Demands From Secondary Materials — and Where FRP Delivers.

Great British Energy awarded a £360 million Owner's Engineer contract to Amentum and Cavendish Nuclear's Litmus Nuclear joint venture for the UK's first Small Modular Reactors at Wylfa, North Wales. The 14-year framework, supported by £2.6 billion in Spending Review funding and £599 million from the National Wealth Fund, marks the transition from technology selection to active engineering delivery. SMR construction is beginning. The secondary infrastructure specification decisions that will govern 60 years of nuclear operational performance are the decisions being made now. Here is where FRP fits.

Published by Reinforce Technology  |  13 July 2026

The UK's Small Modular Reactor programme reached a significant delivery milestone last week. Great British Energy Nuclear appointed the Litmus Nuclear joint venture, comprising Amentum and Cavendish Nuclear, as Owner's Engineer for the Rolls-Royce SMR deployment at Wylfa in North Wales. The contract, valued at up to £360 million including VAT, runs until 2040 with a possible extension to October 2041, covering front-end engineering, licensing support, design assurance, and constructability input across the programme's multiple delivery phases (New Civil Engineer, 2026). The appointment follows the £2.6 billion allocation in the 2025 Spending Review, the National Wealth Fund's commitment of up to £599 million to Rolls-Royce SMR, and the April 2026 signing of the technology delivery agreement that initiated detailed design activities and regulatory engagement (World Nuclear News, 2026).

The Rolls-Royce SMR is a 470 MWe pressurised water reactor designed for modular manufacture, with 90% of the reactor built in factory conditions and assembled on site. The design targets a 60-year operational life, generating consistent baseload low-carbon electricity from a standardised, repeatable platform that Rolls-Royce has stated can be deployed across multiple UK sites using the same construction methodology (World Nuclear News, 2026). Wylfa is planned to host three reactors initially, with potential for up to eight, with a final investment decision targeted for 2029. AtkinsRéalis has separately been awarded a five-year civil works contract at Sizewell C, and SGE has unveiled plans for 14 UK SMRs alongside the existing Hinkley Point C and Sizewell C large-scale programmes. The UK nuclear construction pipeline in 2026 is more active than at any point since the original fleet was built.

For the engineering and supply chain community working across this pipeline, the secondary infrastructure specification decisions being made during the current engineering and design phases will govern the performance and maintenance requirements of these assets for the full 60-year operational life. Nuclear environments place specific and well-documented demands on secondary structural materials — demands that galvanised steel does not fully meet and that FRP addresses consistently and intrinsically. This blog sets out those demands precisely, for the secondary infrastructure applications where FRP is the correct specification in nuclear and SMR environments, and with honest acknowledgment of the applications where it is not.

Great British Energy awarded a £360 million Owner's Engineer contract for the UK's first SMRs at Wylfa this week. The Rolls-Royce 470MWe design targets a 60-year operational life — the horizon over which secondary infrastructure inside and around these facilities must perform.

Why Nuclear Environments Place Specific Demands on Secondary Materials

Nuclear infrastructure creates a secondary material specification environment that is more demanding than almost any other category of UK construction, for reasons rooted in both the operational requirements of the facility and the regulatory framework that governs it. Understanding these demands precisely is the starting point for correct specification, and for being honest about where FRP is the right answer and where it is not.

The first and most specific demand is non-magnetic behaviour. Nuclear facilities use radiation survey instrumentation throughout their operational lives to monitor dose rates, contamination levels, and the integrity of radiological controls. These instruments rely on sensitive detectors that can be affected by the magnetic fields generated by ferromagnetic materials in close proximity. Secondary structural steel in the vicinity of radiation monitoring positions creates a local magnetic environment that can interfere with instrument readings, potentially introducing errors into the radiological measurements that nuclear safety relies upon. FRP is entirely non-magnetic. Structural profiles, grating, walkways, and cable management specified in FRP do not generate or interact with magnetic fields at any point in the material (IntechOpen, 2022).

The second demand is non-sparking behaviour. Nuclear facilities include zones where hydrogen accumulation is a potential hazard, including battery rooms providing emergency power backup, certain areas of the fuel handling system, and enclosed spaces where radiolytic hydrogen generation from reactor water chemistry can occur. In these zones, any secondary structural material that could generate a spark under mechanical impact or friction is a potential ignition source that nuclear safety cases must address. FRP structural profiles and grating are non-sparking under all normal operational and foreseeable accidental loading conditions, eliminating this ignition risk from the secondary structural envelope of the facility (IntechOpen, 2022).

The third demand is corrosion resistance in the specific chemical environments of nuclear plant operations. Cooling water systems, spent fuel storage pools, and the operational chemistry of a pressurised water reactor all create environments where secondary structural materials at or near the water surface are exposed to boric acid solutions, controlled pH chemistry agents, and in some areas the combination of radiation and moisture that can accelerate material degradation mechanisms not present in conventional industrial settings. FRP in vinyl ester or epoxy resin systems provides broad-spectrum resistance to the controlled chemistry environments of nuclear cooling and treatment systems, without the corrosion mechanism that depletes galvanised steel coatings in these conditions (IntechOpen, 2022).

The fourth demand is a 60-year operational design life. A nuclear power station is the longest-lived category of industrial infrastructure in the UK economy. Secondary infrastructure that requires maintenance, recoating, or structural replacement before the end of a 60-year design life generates access events in a radiologically controlled environment where every access requires radiation dose planning, permit-to-work authorisation, contamination controls, and post-work monitoring. In high-dose areas, the ALARA principle, As Low As Reasonably Achievable, specifically drives specification toward materials that minimise the frequency and duration of maintenance access across the facility's operational life. A secondary material that requires no maintenance across 60 years delivers a directly quantifiable ALARA benefit over galvanised steel, which requires periodic intervention across the same period (IntechOpen, 2022).

Where FRP Is Specified in Nuclear and SMR Infrastructure

1. Grating and Walkways in Controlled Areas

Access grating and walkway systems in nuclear controlled areas — the areas around reactor systems, primary coolant equipment, and spent fuel handling — operate in the combination of radiation environment, controlled chemistry, and strict contamination management that nuclear facilities require. Metal grating in these areas must be managed within the radiological controls of the facility: cleaned, surveyed for contamination, and in some cases replaced as the facility ages and contamination management requirements evolve. FRP moulded grating provides a smooth, non-porous surface that can be decontaminated effectively using the cleaning agents used in nuclear controlled areas, does not corrode in the controlled chemistry environments of nuclear plant operations, and does not contribute magnetic interference to radiation monitoring instrumentation in the vicinity.

In the modular construction methodology of the Rolls-Royce SMR design, where 90% of reactor components are factory-built and assembled on site, secondary structural elements including grating and walkways for the reactor module are among the components that benefit most from the standardisation and quality control of factory manufacture. FRP moulded grating panels, manufactured to consistent dimensions and surface specifications under quality management systems, are well-suited to the factory-build approach that the SMR programme's cost model depends on for repeatable, lower-cost deployment across multiple sites.

2. Cable Management in Electrical and Instrumentation Systems

Nuclear facilities are electrically intensive, with multiple independent and diverse electrical systems providing power to safety-classified equipment. The cable management routing these systems must meet specific fire performance requirements under nuclear safety regulations, must not introduce electromagnetic interference into safety instrumentation, and must perform for the full operational life of the facility without maintenance-driven replacement that would require access to electrical cable routes in potentially active radiological areas.

FRP cable trays in nuclear facilities provide non-conductive, non-magnetic cable management that does not generate electromagnetic interference with safety instrumentation, is corrosion-resistant in the controlled chemical environments of nuclear plant buildings, and is available in fire-retardant formulations tested to the fire performance classifications required under nuclear facility fire safety assessments. The non-magnetic property is specifically relevant for instrumentation cable management in areas where radiation monitoring cables run parallel to power cables, where magnetic interference from conductive cable management could affect signal integrity in safety-classified measurement circuits.

3. Structural Profiles for Secondary Framing and Equipment Supports

Secondary structural framing for equipment supports, pipe hangers, cable management supports, and access platform primary framing in nuclear facilities operates in the same demanding environment as the grating and cable management, with the additional requirement of structural performance across a 60-year design life in environments where periodic inspection and assessment of secondary steel structures generates dose accumulation for the maintenance personnel involved. FRP pultruded structural profiles for secondary framing in nuclear facilities provide structural sections that do not require corrosion maintenance inspections across their operational life, do not contribute to radiation dose accumulation through maintenance access events, and do not generate magnetic interference with the radiation monitoring instrumentation that nuclear safety depends upon.

4. Perimeter Fencing and Security Infrastructure

Nuclear facilities are classified as Critical National Infrastructure and require physical protection systems of a standard consistent with their nuclear security category. Perimeter fencing and security infrastructure at nuclear sites must meet the physical protection requirements of the relevant nuclear site licence and security plan. FRP mesh perimeter fencing provides non-conductive, non-magnetic, corrosion-immune boundary infrastructure that does not interfere with the radar, CCTV, and electronic detection systems that nuclear site physical protection plans deploy, has no scrap metal value, and does not contribute to the electromagnetic interference that metal fencing can generate around sensitive perimeter detection systems.

FRP grating, cable trays, structural profiles, and perimeter fencing in nuclear and SMR environments are non-magnetic, non-sparking, and corrosion-immune — the combination of properties that nuclear secondary infrastructure demands across a 60-year operational design life.

Where FRP Is Not the Correct Specification in Nuclear Infrastructure

An honest assessment of FRP in nuclear environments requires being specific about the applications where it is not the right answer. Standard FRP formulations are combustible, and nuclear safety cases include fire as a specific design basis event requiring analysis and mitigation. In areas where fire resistance is a safety-classified requirement — fire barriers, cable penetration seals, and fire-rated structural elements — standard FRP does not meet the requirement. Fire-retardant FRP formulations significantly improve fire performance and are available for applications where flame spread and smoke generation are the primary concerns, but the fire resistance of FRP structural sections under sustained fire loading is not equivalent to steel, and nuclear safety cases must reflect this distinction accurately.

Primary structural elements in nuclear facilities, including reactor building primary frames, crane structures, and primary equipment supports, are typically specified in steel or reinforced concrete for the combination of strength, ductility, and fire resistance that primary nuclear structural engineering requires. FRP is not the correct specification for these primary structural applications. Its role in nuclear infrastructure is in secondary and tertiary structural applications, cable management, access systems, and perimeter infrastructure, where its non-magnetic, non-sparking, corrosion-resistant, and maintenance-free properties provide genuine advantages over steel alternatives without the primary structural demands that steel continues to satisfy more effectively.

The SMR Opportunity and the Specification Decisions Being Made Now

The UK SMR programme represents the most significant new nuclear construction opportunity the UK has seen since the original fleet was commissioned. Three reactors at Wylfa, potentially eight in total at the site, with SGE's plans for 14 further SMRs across multiple UK locations, and the existing Hinkley Point C and Sizewell C programmes providing concurrent large-scale nuclear construction activity. The secondary infrastructure specification decisions being made during the current engineering and design phases of these programmes will be replicated across every reactor in the fleet, because the repeatable construction model that makes SMRs cost-competitive depends on standardised specifications applied consistently across multiple units.

The Owner's Engineer appointment announced this week places Amentum and Cavendish Nuclear in the position of providing independent technical assurance across design, engineering, and constructability for the Wylfa programme. The specification decisions made during this engineering phase, including secondary infrastructure material specifications, will inform the standardised plant layout that the SMR programme's repeatable construction model requires. Getting those specifications right in the engineering phase is significantly more effective than revising them later, and the nuclear secondary infrastructure specification case for FRP, non-magnetic, non-sparking, corrosion-resistant, maintenance-free across 60 years, is made most effectively at the engineering stage when it can be incorporated into standardised specifications that apply across the full fleet.

The UK's nuclear programme is more active than at any point in a generation. The Wylfa SMR Owner's Engineer appointment marks the transition from technology selection to active engineering delivery across a 14-year framework. The secondary infrastructure specification decisions being made in that framework will govern 60 years of nuclear operational performance. FRP's non-magnetic, non-sparking, corrosion-resistant, and maintenance-free profile aligns precisely with what those 60 years demand from secondary materials — and the engineering phase is exactly the right time to make that case.

Reinforce Technology FRP Products for Nuclear and SMR Infrastructure

Reinforce Technology supplies FRP cable trays, grating, structural profiles, and perimeter fencing for nuclear and advanced energy infrastructure. Available in vinyl ester and epoxy resin systems, with fire-retardant formulations tested to relevant fire performance classifications for fire-sensitive nuclear applications. All products are non-magnetic, non-sparking, and corrosion-immune, with full material traceability documentation and quality management system certification available for nuclear project QA submissions.

Contact us to discuss your nuclear or SMR project and the correct FRP specification for your specific secondary infrastructure application and radiological environment.

Final confirmation of suitability for any specific nuclear application, including fire performance classification requirements under the facility's nuclear safety case and radiological environment assessments, remains the responsibility of the appointed nuclear project engineer and safety case holder. Reinforce Technology provides technical guidance and material recommendations based on information supplied to us. Specification and nuclear safety sign-off should always sit with the qualified professionals responsible for the engineering and nuclear safety of the installation.

References

IntechOpen (2022) 'Fibre-Reinforced Polymer (FRP) in Civil Engineering', in IntechOpen Engineering Series. Available at: https://www.intechopen.com/chapters/84203 [Accessed: 13 July 2026]. [Non-magnetic and non-sparking properties; corrosion immunity; maintenance-free design life].

NACE International (2016) International Measures of Prevention, Application and Economics of Corrosion Technology (IMPACT). Houston, TX: NACE International. Available at: http://impact.nace.org/economic-impact.aspx [Accessed: 13 July 2026].

New Civil Engineer (2026) Great British Energy Appoints Amentum and Cavendish in £360M SMR Deal. Available at: https://www.newcivilengineer.com/latest/great-british-energy-appoints-amentum-and-cavendish-in-360m-smr-deal-06-07-2026/ [Accessed: 13 July 2026]. [14-year contract from April 2026 to April 2040; possible extension to October 2041; £360m including VAT; front-end engineering, licensing, constructability input across multiple SMR sites].

World Nuclear News (2026) Contract Signed for Delivery of UK's First SMRs. Available at: https://www.world-nuclear-news.org/articles/contract-signed-for-delivery-of-uks-first-smrs [Accessed: 13 July 2026]. [Rolls-Royce and GBE-N contract signed; National Wealth Fund £599m commitment; £2.6bn Spending Review allocation; three SMRs at Wylfa initially, up to eight potential; final investment decision 2029; 90% factory-built; 60-year operational life].

Younis, A., Ebead, U. and Judd, S. (2018) 'Life cycle cost analysis of structural concrete using seawater, recycled concrete aggregate, and GFRP reinforcement', Construction and Building Materials, 175, pp. 135-144. doi: 10.1016/j.conbuildmat.2018.04.183.