Above: A four-day, 8991 cubic metre continuous reinforced structural concrete pour, marked the completion of the common raft for Hinkley Point C’s second reactor (Photo credit: EDF Energy)


IN JUNE, EDF ENERGY ANNOUNCED it had completed the 49,000-metric-tonne concrete basemat for the second EPR reactor at Hinkley Point C in Somerset. The milestone was achieved “on schedule”, despite the coronavirus pandemic and a reduction of “more than half” in the number of workers on site since March.

Completion came less than a year after the basemat was finished for the first 1630MW reactor at the Hinkley Point
C power plant, which is owned by EDF Energy (66.5%) and China General Nuclear Corporation (33.5%). The target date for this first key milestone (referred to as J0) was set four years ago. Completion now marks the transition from below- ground activity to the construction of permanent reactor buildings above ground.

EDF Energy says Hinkley Point C2 benefited from experience gained on the first identical unit, which “led to significant increases in productivity through steps such as increased use of prefabrication.” This approach is expected to benefit the proposed follow-on project at Sizewell C in Suffolk, which has recently applied to the UK government for planning permission.

Tom Greatrex, chief executive of the UK’s Nuclear Industry Association, welcomed the milestone, noting that the Hinkley Point C power station “represents a big step towards net zero emissions.” Once completed, around 2025, the power station is expected to provide around 7% of the UK’s electricity, offsetting an estimated 9 million tonnes of carbon dioxide emissions annually.

Hinkley Point C is just the start, according to Greatrex. “It also shows nuclear’s large-scale green growth opportunities are real, and there is more to come,” he says.

This view is echoed in a new report — Nuclear for Net Zero — released in mid-June by the independent, non-profit, Energy Systems Catapult, which was set up to accelerate the transformation of the UK’s energy system.

The report is based on an extensive whole system analysis and finds that an optimised approach to delivering a net zero energy system includes a “significant proportion” of new nuclear capacity.

The report recommends — providing costs come down — at least a further 10GW of new established reactor designs are built. Without nuclear, it says, a UK net zero energy system “is possible but risky” and “potentially expensive”. It could, for example, require significant bioenergy and land-use change, as well as “a vast quantity of renewable energy”.

In September 2019, EDF Energy put the cost of the twin-unit Hinkely Point C project at between £21.5bn and £22.5bn ($28bn), up from an initial estimate of $16bn in 2015. The latest increase, EDF says, reflects “challenging ground conditions”, “revised action plan targets” and "the extra costs needed to implement the completed functional design…for a first-of-a-kind application in the UK."

EDF Energy would like to transfer experienced workforce from Hinkley Point to Sizewell C, reasoning that this is the best way to minimise costs and raise standards. But the timing will be critical. If the delay between the two projects is too long, there is a risk that experienced teams will move to other projects.

Data from CGN’s new-build experience in China demonstrates how the fleet effect can reduce risks and costs. CGN saw almost a 20% reduction in overall cost from the first-of-a-kind to the fourth unit, with most of the costs saved in the project management organisation, according to a presentation made by Alan Raymant, CEO of the Bradwell B project at the UK’s Civil Nuclear Showcase in March.

China General Nuclear (66.5%) and EDF Energy (33.5%) are consulting on plans to build a UK HPR1000 nuclear power station at Bradwell-on-sea in Essex until 1 July. The design is currently in the final step of the UK Office for Nuclear Regulation’s four-stage generic design assessment process. The reference plant for the design is CGN’s Fangchenggang 3 in China, which started construction in 2015 and is scheduled for grid connection in 2022.

“Costs can be reduced through repeat build and new construction techniques — but also, and most significantly, with a different approach to financing,” says Greatrex.

The framework chosen for Hinkley Point C — a contract for difference model — has satisfied neither the government nor EDF. The strike price (£92.50/MWh for 35 years) was agreed in 2012 and is rising with inflation as strike prices agreed for other renewable energy projects tumble.


Above: Rapid progress is being made on Hinkley Point C1, which achieved its own J0 milestone last June (Photo credit: EDF Energy)


The government is considering a regulated asset based (RAB) model for future projects (including for Sizewell C) that would see consumers pay upfront through their energy bills. The RAB model was applied successfully for the first time in 2016 to a single asset construction project — the Thames Tideway Tunnel sewerage project. However, because payments would begin immediately and interest would be paid off during construction, it leaves the risk of a stranded asset and rising costs with customers.

Ultimately the government’s decision on the RAB model is waiting on a policy White Paper that was due to be published last year. It was delayed by Brexit, the UK’s general election and now by COVID-19. There are rumours that hopes it would be published this summer are over- optimistic and it could be delayed until 2021. Meanwhile, the Sizewell C team can start only preparatory work, at its own cost. Uncertainty over the financial framework for the plant can only delay getting it to financial close.

Financing issues have already affected Horizon Nuclear Power’s proposed Wylfa Newydd project in North Wales. Development of two proposed UK advanced boiling water reactors (UK ABWRs) on Anglesey was suspended early in 2019, after the UK subsidiary of Hitachi failed to reach a funding deal with the UK government. The exact financing model under discussion wasn't clear. However, Horizon has already spent over £2bn in developing Wylfa Newydd and is determined to get the project restarted.

Horizon's chief executive Duncan Hawthorne welcomed the recent report from Energy Systems Catapult.

“This report shows yet again how nuclear, alongside other clean technologies, can and must be part of the UK’s low carbon future. The analysis also, rightly, sets out the challenge to the industry in terms of cost reduction and we are confident — given our proven design and world-leading partners — we can deliver against this,” he says.

An operational Wylfa Newydd would provide enough clean electricity to meet all of Wales’ power demand, domestic and industrial. This would, effectively, make Wales’ electricity supply net zero by the early 2030s, he adds.

Looking beyond large reactors, Nuclear for Net Zero modelling also strengthens the case for a small, light-water modular reactor programme.

It goes on to describes how nuclear could play a big part in driving the growth of the hydrogen economy and providing district heating.

“Ultimately, if nuclear is able to fulfil its cost reduction potential, and contribute to the challenges of decarbonising heat and hydrogen, around 50GWe of nuclear may be needed by 2050,” the report finds. However, it notes there is “significant uncertainty” about the mix within a 50GWe nuclear portfolio, which underlines the importance of stage-gated approaches for both light-water SMRs and advanced reactors.

The report concludes that change is required if the UK is to get on track for net zero by 2050. “If nuclear is to fulfil its potential role in decarbonising the energy system, then the policy framework must change.” Both government and the nuclear sector have a role to play in leading and enabling such a change, it adds.

The UK’s Nuclear Innovation Research and Advisory Board (NIRAB) made similar recommendations in its latest annual report to BEIS, proposing a target for the first commercially operating SMR by 2030. It also said the government should enable nuclear’s contribution to wider energy decarbonisation by investing in advanced reactor systems including high-temperature gas reactors. It recommends public investment of £1bn in this area over five years from April 2021 (£400m for R&D and £600m for advanced reactor demonstration).

“It would be prudent to plan for nuclear energy to provide at least half of the firm low-carbon electricity not provided by renewables,” NIRAB says.