We are using more and more renewable energy in our power system – 47 per cent of electricity came from renewable sources in the first three months of 2020 – but we cannot decarbonise our economies unless we also tackle carbon dioxide (CO2) emissions from using fossil fuels in power and other sectors. Two of the most promising ways to do this are to decarbonise hydrogen production and to capture emissions using carbon capture and storage (CCS) – and they go hand in hand.
Because of its versatility, hydrogen will be crucial if the UK is to meet its 30-year target of bringing greenhouse gas emissions to net zero. Hydrogen can do many things: store energy long-term to cover seasonal lulls in wind or solar generation; fuel heavy transport such as ships, trucks and trains; replace fossil fuels in so-called “hard-to-abate” industries such as steelmaking; and be used as a clean and flexible fuel source in power generation.
So, to cut emissions, we will need to create a hydrogen economy, and for the hydrogen economy to succeed, CCS is crucial.
CCS poised to take off
CCS takes the CO2 emissions from power stations and industrial facilities and stores them underground, and it will be central if the UK is to reduce CO2 emissions to net zero by 2050, say experts including the International Energy Agency (IEA) and the UK’s Committee on Climate Change.
“You can’t have a credible conversation about net zero without talking about CCS,” says Luke Warren, chief executive of the Carbon Capture and Storage Association (CCSA). While we have spent the last couple of decades successfully decarbonising electricity by developing renewable power and phasing out coal, “what comes next will be more difficult,” says Warren.
Natural gas and oxygen from an Air Separation Unit enters the reformer.
A partial oxidation reaction takes place, with the output flowing through the catalyst bed which performs the reformation.
The synthetic gas produced is then separated, creating pure streams of hydrogen (H2) and CO2
The CO2 is transported by pipeline to be permanently stored deep underground.
The hydrogen is transported for use in power, industry, heat and transport.
Less than 20 miles from the Humber Bridge lies the Saltend Chemicals Plant, the intended location of the largest hydrogen plant in the world.
Hydrogen at scale is crucial for meeting climate targets
To reach net zero targets, says José Miguel Bermúdez Menéndez, energy technology analyst for hydrogen and alternative fuels at the IEA, hydrogen demand needs to increase seven-fold, but that hydrogen also needs to become ‘low-carbon’. Currently, hydrogen is mostly made from natural gas and its global production releases 830 million tonnes of CO2 a year. This is known as grey hydrogen. There are two principal ways to produce low carbon hydrogen: use renewable electricity and electrolysis to split the H from H2O (water) to produce what is known as green hydrogen; or produce it from natural gas and capture the CO2 by-product. This is known as blue hydrogen.
Tap the roundels to explore the main ways hydrogen is produced
Grey or black hydrogen is produced using natural gas, oil, or coal as a feedstock with the CO2 by-product emitted directly into the atmosphere.
Blue Hydrogen is produced from natural gas, with carbon capture and storage (CCS) technology. Carbon capture technologies prevent CO2 being released, enabling the captured carbon to be safely stored deep underground or utilized in industrial processes.
Green hydrogen is the cleanest variety, producing zero carbon emissions. It is produced using electrolysis powerered by renewable energy, like offshore wind, to produce a clean and sustainable fuel.
In the long run, as renewable energy generation capacity increases and the cost of electrolysers falls, green hydrogen will become dominant, but today blue hydrogen is cheaper, “so it makes sense to focus on blue hydrogen to build capacity and the hydrogen market,” Bermúdez Menéndez says.
Developing a UK hydrogen market
The UK hopes to produce blue hydrogen at industrial clusters around the country. The biggest is in the Humber region, where Zero Carbon Humber aims to enable industrial facilities and power plants to either fuel-switch to hydrogen or capture their CO2. All captured CO2 will be pumped into naturally occurring aquifers under the North Sea to be permanently stored.
The anchor project for the initiative will be the H2H Saltend hydrogen production plant at Saltend Chemicals Park in Hull, which each year produces 3.5m tonnes of the region’s 12.4m tonnes of industrial CO2 emissions. H2H Saltend, led by energy group Equinor, will be the largest blue hydrogen plant in the world.
Growth opportunities for the UK at Saltend Chemicals Park
Concept is illustrative only
“H2H Saltend will enable industrial customers in the park to fully switch over to hydrogen, and the power plant there to move to a 30 per cent hydrogen to natural gas blend. Emissions from Saltend Chemicals Park will reduce by nearly 900,000 tonnes of CO2 per year,” says Daniel Sadler, UK director of Low Carbon Strategy at Equinor.
As it expands, H2H Saltend will be able to provide hydrogen to other industrial users across the region, such as British Steel’s facility at Scunthorpe, which could become one of the first producers of low-carbon steel. “The potential in the Humber is unparalleled anywhere else in Europe,” says Sadler.
H2H Saltend and Zero Carbon Humber will help preserve the region’s 55,000 manufacturing jobs and enable the creation of a large-scale hydrogen network, as well as creating a network to transport and store captured CO2 from the region’s oil refineries and power stations.
Fuel switching to hydrogen could also create around 43,000 new jobs in energy-intensive industrial sectors across the UK.
No clean hydrogen without CCS
Being able to store the CO2 captured is crucial to H2H Saltend and other Humber projects. The facility’s location on the North Sea coast is close to the Endurance aquifer, which is large enough to store CO2 from both the Humber and the Teesside industrial cluster further north.
“We need hydrogen at a really significant scale to be developed over the course of the 2020s,” says Warren. “Until we have large enough amounts of renewable energy, it will be hard to do that with green hydrogen, so blue hydrogen will be a key enabler of the hydrogen economy.”
We need hydrogen at a really significant scale to be developed over the course of the 2020s.
“That means we need to scale up CCS too – it is the pillar that supports the development of clean hydrogen. There is an opportunity for the North Sea to become a world-leading hub for hydrogen and CCS in the same way as it has in offshore wind,” he concludes.