UK hydrogen strategy: a role for nuclear?15 September 2021
Hydrogen is attracting growing interest worldwide, not least in the UK, where an H2 strategy has recently been launched. The nuclear industry sees significant opportunities
In common with many other countries, the UK now has a hydrogen strategy. The UK’s first such strategy was published on 17 August and “sets out the approach to developing a thriving low carbon hydrogen sector in the UK to meet our ambition for 5GW of low carbon hydrogen production capacity by 2030.” Hydrogen is seen as “a new low carbon solution which can help the UK to achieve net zero by 2050, and [its] Sixth Carbon Budget target by 2035.”
The strategy outlines: how the UK will rapidly and significantly scale up production and lay the foundations for a low carbon hydrogen economy by 2030; and how?government will support innovation and stimulate investment in the 2020s?to scale up low carbon hydrogen. It also sets out the UK’s “twin-track approach”, supporting both electrolytic ‘green’ and carbon capture (CCUS)-enabled ‘blue’ hydrogen production.
The strategy does not particularly emphasise nuclear power but recognises its potential as a route to low carbon hydrogen, mentioning both low temperature nuclear electrolysis (employing existing nuclear facilities) and high temperature nuclear electrolysis (employing advanced nuclear reactors in the 2030s), as well as direct thermochemical splitting of water using “very high temperature heat from advanced modular nuclear facilities” in the mid to late 2030s.
Tom Greatrex, chief executive of the UK Nuclear Industry Association (NIA), interprets the strategy as confirming that “nuclear reactors, large, small, current and advanced, have a critical role in producing low-carbon hydrogen”, observing that “nuclear is the only source of energy that can produce clean power and clean heat, making it a vital component as we decarbonise sectors beyond electricity.” Whether labelled as ‘green’ or ‘low carbon’, “it’s only hydrogen from zero emissions sources like nuclear and renewables that can make a meaningful long-term impact on decarbonisation”, he says, and recommends that “the government must now swiftly implement a new financing model for nuclear to cut costs, move forward with Sizewell C, and continue to support the development of modular reactors, to ensure nuclear is part of a strong low-carbon hydrogen mix.”
Just ahead of the government hydrogen strategy publication, the UK nuclear industry launched a report setting out what it called a “cross-sector plan for zero carbon hydrogen from nuclear.”
The new report, from the Nuclear Sector Deal’s Innovation Group, sets out what it sees as a series of “urgent and important recommendations for realising the opportunity of zero carbon hydrogen from nuclear.”
The report, Unlocking the UK’s Nuclear Hydrogen Economy to Support Net Zero, follows on from a Nuclear Hydrogen Roundtable event in May 2021, which brought together over 80 “experts and industry leaders from across the hydrogen value chain.”
Timed to “offer maximum value ahead of the UK government’s anticipated hydrogen strategy”, the report stressed the scale of the challenge ahead for deep decarbonisation yet the enormity of what nuclear derived hydrogen could deliver. It sets out actions for industry and commitments for government which, it believes, will help the UK secure net zero emissions on time and on budget.
In a foreword to the report, Dr Fiona Rayment, chair of the Innovation Group, summarises the key findings as follows:
? Nuclear derived hydrogen can be a low-risk route to hydrogen production, both today and in the future.
? Through a cross-sector approach, significant quantities of nuclear derived hydrogen could be produced at scale to fully support the challenging energy transition.
? A first use case applied now will contribute to meeting today’s policy requirements and demonstrate the entire value chain from production to user.
The action plan establishes the pathway for achieving this with consideration of the necessary economic, technical, regulatory, policy and financial drivers. Its successful delivery would mean not only maximising already commercialised technology, capable of being deployed now, but also driving innovation in technologies which offer further efficiencies and value for money.
Describing the significance of the timing of the report, Dr Fiona Rayment said:
“With decades of nuclear experience, the UK sits on a wealth of skills, talent and capability that can deliver nuclear derived hydrogen at scale. This capability can create the world’s first nuclear derived hydrogen economy, delivering net zero at lower cost to consumers. The UK could spur a future global commodity market for hydrogen, enhancing exports of skills and innovative technology.
“I very much hope and expect that, given its scope and timing, this document will be seen as a turning point for the role of nuclear in the future hydrogen economy and a call to action for the sector to take this one-time opportunity and grab it with both hands. This is an opportunity that can be realised only with true cross-sector collaboration.”
In February the UK Nuclear Industry Association published the nuclear sector Hydrogen Roadmap, following on from Forty by ’50: The Nuclear Roadmap. This noted that “grey” hydrogen currently predominates, although it produces 10kg of emissions for every 1kg of hydrogen produced, but suggested that, as technology develops, there will be four ways in which nuclear power can produce hydrogen:
1. Cold water electrolysis — electricity from a power station is used to split water into hydrogen and oxygen. This requires diverting the electricity produced by the station from the grid to an electrolyser. The Hydrogen to Heysham project (H2H) investigated this process, which is available today and has been proven at a small-scale. The process is the cheapest currently available. It involves the cost of the electrolyser, the cost of storage, as well as the normal costs of producing the electricity.
2. Steam electrolysis — high-temperature steam electrolysis takes place between around 600-1000°C and requires a third less energy than cold water electrolysis and is therefore expected to be more efficient. Use of lower temperature heat can also increase the electrolysis efficiency, though not as much as in the
600-1000°C range. For instance, initial EDF analysis indicates that using low temperature heat (c. 150-200°C) from UK EPRs to support steam electrolysis will be technically feasible — via heat exchangers to achieve the required operating temperatures — and will offer efficiency benefits over cold water electrolysis. Steam electrolysis is technology available today.
3. Thermochemical water splitting — heat between 600-900°C produced by an advanced modular reactor (AMR) in the presence of chemical catalysts can be used to cause water to split into hydrogen and oxygen. The current generation of reactors do not produce temperatures high enough for this process. The UK government has, however, recognised that AMRs “could operate at over 800°C and the high-grade heat could unlock efficient production of hydrogen.” AMRs could both produce clean power and clean hydrogen simultaneously.
4. Reforming fossil fuels — waste heat from nuclear power could provide the high temperatures for the steam reforming process instead of fossil fuels, but as carbon dioxide is released, this would need to be accompanied by carbon capture and storage.