Hydrogen is already a big business. Global demand stood at 130 million tonnes in 2020, being expected to grow to over 500 million tonnes annually, in 30 years. To achieve that, a nuclear-hydrogen combination is on the equation.
As governments around the world are committing to reaching net zero emissions by 2050, many countries are looking at the role hydrogen can play in mitigating climate change. By 2035 the world will require millions of tonnes of clean hydrogen but it can only fully contribute to decarbonisation if it is produced from low-carbon energy sources and its production does not crowd out decarbonisation of other parts of the energy system.
In the future, more industries are expected to turn to hydrogen, to replace fossil fuels in sectors such as steelmaking and others where electricity cannot be used, such as heavy transport including trucking and rail services.
In the medium term, new innovations will also allow hydrogen to be produced in different and more efficient ways, including from fossil fuels coupled with carbon capture, and advanced nuclear technologies such as next generation small modular reactors (SMRs). At the moment, SMRs (usually less than 300MW) are still in an early phase, with many pilot projects in the pipeline and gaining momentum.
These advanced nuclear technologies will use significantly higher temperatures (>700°C) to produce nuclear-hydrogen efficiently through thermo-chemical processes that will require inputs of water and heat.
How does the nuclear-hydrogen nexus fit together in practice?
Great Britain is an expecting testing hub, as there is political support for both a fleet of new reactors and a switch to hydrogen to decarbonise industry and transport. Although electricity can obviously be transported across country to power electrolysers, nuclear’s key heat offering cannot be transported in the same way. Even for electricity, limited grid capacity is already causing huge constraint costs and building new network is a slow and costly process. That means siting issues are make or break for a nuclear-hydrogen production.
Beyond electrical power, nuclear’s ability to generate even larger quantities of heat also offers an opportunity in hydrogen production. Heat is crucial for steam methane reforming, as the name implies. In current deployment the heat is supplied using additional gas to create steam. That has the benefit of simplicity but it increases gas consumption by up to a third so alternate heat sources that don’t use fossil fuels are attractive.
Using electricity from nuclear to produce hydrogen is relatively flexible on siting as it can be transmitted across country. Using nuclear’s heat is the opposite: practically, it cannot be transported long distances.
Water stresses
Currently, water use is 9-14 kg per kg of hydrogen produced (depending on the amount of demineralisation required), with some estimates as high as 18 kg per kg. Methane reforming requires 6-13 kg of water per kg of hydrogen produced. To put it another way, a typical estimate is that when working consistently a 1 MW electrolyser will produce around 400 kg of hydrogen per day. That suggests water use of 3.6-5.2 cubic meters per day.
Pipeline issues
Today, hydrogen is transported from the point of production to the point of use via pipeline and on the road in cryogenic liquid tanker trucks or gaseous tube trailers. Pipelines are deployed in regions with substantial demand (hundreds of tonnes per day) that is expected to remain stable for decades.
This means that hydrogen producers using the methane reforming route have to be sure that the gas assets they are using will have a methane supply in the long term – which excludes pipes that may be converted to transporting hydrogen.
This issues are no news to energy developers, but the uncertainties of a nuclear-hydrogen production may be a challenge for the industry investors.
Universal Kraft and Universal H2 work together to be on the forefront of the hydrogen growth. With our expertise and futuristic vision, we deliver optimal solutions to produce, store and distribute green hydrogen from 100% renewable energy. Know more about our projects here.