IN Brief:
- Holtec and EDF have submitted a proposal for up to four SMR-300 reactors at the former Cottam power station site.
- The Nottinghamshire project could deliver around 1.3GW of nuclear capacity on a former coal-generation location.
- The proposal links brownfield energy reuse, grid infrastructure, and future modular nuclear construction.
Holtec International and EDF have submitted a proposal for up to four SMR-300 small modular reactors at the former Cottam coal-fired power station site in Nottinghamshire, setting out plans for a potential 1.3GW nuclear development on a major brownfield energy location.
The proposal would reuse an established power generation site with industrial land history, grid relevance, and a long-standing connection to the UK energy system. Holtec has positioned the Cottam project as a potential second-of-a-kind deployment following its planned SMR-300 project at Palisades in Michigan.
Cottam’s former coal role gives the site strategic value because energy transition increasingly depends on reworking existing infrastructure rather than developing every asset from a blank site. Former power stations can offer grid corridors, transport links, industrial planning context, technical skills, and established supply-chain familiarity, although each site still requires detailed consenting, environmental assessment, and engineering validation.
The SMR-300 is Holtec’s pressurised water reactor design. Any Cottam development would still need further approvals, investment decisions, supply-chain commitments, construction planning, and regulatory progression before activity could begin at scale.
Small modular reactors are often described in manufacturing terms because their commercial case depends on repeatability, standardisation, and controlled production. The construction workload remains substantial. A live scheme would require enabling works, earthworks, nuclear island construction, balance-of-plant structures, cooling systems, security infrastructure, access roads, temporary works, utilities, grid connection, logistics planning, and commissioning facilities.
The electricity system around projects of this type is already under heavy reinforcement pressure. National Grid’s request for additional transmission reinforcement funding reflects the scale of work needed to connect new generation, manage industrial electrification, and support rising demand from major power users.
New nuclear construction cannot be separated from that grid context. A reactor programme needs network capacity, substations, connection planning, protection systems, civil interfaces, controls, outage coordination, and supply-chain availability across both the generating site and the wider transmission system. The ability to connect reliable low-carbon capacity will influence how quickly any project can move from proposal into deliverable infrastructure.
SMRs are intended to reduce some of the programme risk associated with large bespoke nuclear builds, but standardisation only delivers savings if design stability is maintained across projects. UK site conditions, regulatory evidence, nuclear quality requirements, local consenting, labour availability, and procurement structures can all erode repeatability if they are not managed from the outset.
The Cottam proposal also raises questions about how former coal communities are brought into the next phase of energy construction. Large power stations supported skilled workforces, local suppliers, maintenance contractors, and regional engineering ecosystems. A new nuclear programme could create long-term construction, manufacturing, maintenance, and operational demand, but training and local procurement would need to begin well before peak construction.
Competition for specialist nuclear supply-chain capacity is likely to intensify as the UK pursues both large-scale and modular nuclear options. Nuclear-grade construction management, high-integrity concrete, qualified welding, digital assurance, safety-critical commissioning, and specialist manufacturing are limited resources. Projects that move earliest with credible funding and clear delivery models will be better placed to secure capacity.
Using a former coal site creates a clear industrial logic. It treats energy transition as a process of adapting established infrastructure, skills, and locations rather than abandoning them. That approach could become increasingly important as the UK tries to accelerate low-carbon generation without adding unnecessary land, grid, and consenting complexity.
The proposal now enters a more demanding phase in which technology ambition must be converted into funding, regulation, supply-chain planning, and buildable design. Cottam adds another substantial project to the UK’s low-carbon construction map, where nuclear, transmission, hydrogen, storage, and grid reinforcement are beginning to compete for many of the same contractors, engineers, and specialist suppliers.
