Sizewell C is only the beginning of nuclear and hydrogen

Tom Greatrex

27 November 2020

© EDF Energy

Nuclear power is the most efficient power source in the world. It has among the lowest carbon footprints, and has long been a reliable pillar of our energy production. It is also a versatile technology, suited to the demands of deep decarbonisation. Nuclear power can not only produce huge amounts of zero-carbon electricity, but they can also be used to produce hydrogen. As we look to eliminate emissions from home heating, office heating, industry and aviation, hydrogen provides a valuable zero-carbon supplement where electrification may be difficult.

The challenge with hydrogen is to produce it without emitting more carbon. That is where nuclear comes in. The most common way to produce hydrogen today is to use natural gas in a process called steam methane reformation. For every one kilogram of hydrogen produce, this process emits 10 kilograms of carbon. That is not a serious solution for net zero. Nuclear power, however, can provide electricity to split water into hydrogen and oxygen, with no carbon emissions whatsoever. We call that “green hydrogen.”

We already know this approach will work. The Hydrogen to Heysham project showed that an electrolyser powered by a nuclear reactor can produce hydrogen with 12 times less lifecycle carbon footprint than using the existing steam methane process. Even if carbon capture technology were developed, it would still have five times the carbon footprint of hydrogen from nuclear.

The project team at Sizewell C have taken this further, announcing this week that they were planning to develop a demonstrator project to produce up to 800kg of hydrogen per day using an electrolyser powered by nearby Sizewell B. The hydrogen would fuel some of the vehicles and equipment used to build the new station, reducing the carbon footprint of construction. In the future, when power from nuclear stations was not needed by the grid, it could be diverted into hydrogen production, rather than turned off. That means we could use our zero-carbon power more effectively, driving decarbonisation beyond electricity generation alone

Nuclear holds out much more promise than that for hydrogen. The Government, in its Ten Point Plan, announced hundreds of millions of pounds for Advanced Modular Reactors (AMRs) because they could “operate at over 800°C and the high-grade heat could unlock efficient production of hydrogen and synthetic fuels.” At high temperatures and with the right catalysts, we can split water in hydrogen and oxygen without using any electricity from our power stations. We would get clean power and clean fuel from the same source, without having to sacrifice either. Nuclear power is the only technology that could do this: no other electricity source could produce clean electricity and generate so much heat without producing any carbon. The Government is absolutely right to back such an exciting technology, and its target of a demonstrator AMR by the early 2030s shows the level of ambition we need. Net zero requires us to make decisions now, and to invest now, to keep us on course for the next 30 years. Nuclear and hydrogen is a good place to start.