Hydrogen is considered a crucial contributor to a greener energy system, with the potential to replace natural gas in domestic heating and industrial energy supply and transport.
Celia Greaves, CEO and founder of the UK Hydrogen and Fuel Cell Association (UK HFCA), says that of the new 10GW production target, at least half will be renewably-based electrolytic hydrogen.
This renewable ‘green’ hydrogen is produced using electrolysis, where water is split into hydrogen and oxygen by passing a current (from renewable power sources) through electrodes. ‘Blue’ hydrogen is produced in a carbon-intensive process where natural gas is combined with steam. Blue hydrogen processes generate CO2 as a by-product, but carbon capture and storage (CCS) technology can theoretically be used to make it a low-emissions process – though burying carbon isn’t removing carbon.
Hydrogen produces no carbon emissions when combusted or used in fuel cells, boilers, turbines or engines. It can also be stored at scale and transported like natural gas or liquid fuel, and is widely used in chemical and industrial production. (Hydrogen is also used in industrial processes, such as in agricultural fertilisers and as a reducing agent for producing steel and semiconductors).
Some large vehicles already run on hydrogen, raising hopes it could be a long-term alternative to diesel for freight vehicles where batteries have particular limitations around weight and range, including HGVs, aeroplanes and ships.
“In Europe we're seeing significant commitments to building hydrogen refuelling stations every 100-200km to support vehicles, but we've seen nothing like that in the UK,” Greaves comments.
The UK HFCA produced a report last year that highlighted how, for larger vehicles and cars on longer journeys, hydrogen powered fuel-cell electric vehicles will be the most cost effective low/zero carbon option by 2030 rather than all-electric vehicles.
“The argument for all-electric is spurious unless you have a very unlevel playing field, which is what we have in the UK,” Greaves continues. “There is a renewable transport fuel obligation which, in theory, would help the scale-up of hydrogen as a vehicle fuel, but it is bound by a number of constraints which means it’s not yet optimised.”
The government estimates that hydrogen will need to deliver up to 35% of the UK's energy supply by 2050 if its net zero goals are to be delivered. But the UK currently has almost no low-carbon hydrogen production.
However, ministers say the UK is well-placed to develop a hydrogen industry given its growing capacity for wind power, and have already set aside £240m in a net zero hydrogen fund for projects.
Jon Duffy, CEO of CPH2 (Clean Power Hydrogen), says: “As a business we think we will get to 4GW total yearly production by 2030, which is a decent ramp up, but demand is going to exceed supply for quite a while. The UK has an opportunity to be at the forefront of new green hydrogen technology, but there's a real danger that our government, while it says nice things, is being left behind by the ambition and strategies of other governments.
“At the minute I can see most of our production going abroad, not necessarily because there's going to be less demand here, but other places are just that much further on the journey than the UK, where projects aren’t fully finalised, and funding is not always in place.”
Interim targets
Before the 10GW capacity by 2030 there’s an interim target of 2GW by 2025 for which the government is launching funding calls, including capital funding and operation funding for industry to build and scale-up facilities and establish business models.
“We're asking for a little more flexibility there, because it's not that far away,” explains Greaves. “We don't want to have projects that are in construction or very nearly there to miss out. We need to get on with this, and if we start putting down too many tight boundaries it's going to hamper progress. It's about giving as many projects as possible the chance to come forward and broaden the pool.”
The government has committed to develop two large-scale CCS industrial clusters, one in the North West and one on the east coast. The smaller electrolytic production from renewables-based projects will be more dispersed, and meet a range of different needs, particularly transport – as the hydrogen produced by renewable-based projects is generally of higher purity, which is desirable for transport.
So far, five green hydrogen projects have been awarded a share of around £38million. They include ITM Power, which has been awarded a contract worth £9.3m for its Gigastack project, which will enable it to accelerate both the commercial development of its fourth-generation proton exchange membrane (PEM) electrolyser stack and its new Gigafactory site in Sheffield.
“Currently ITM has a capacity of 1GW per annum,” says Charles Purkess, ITM Power director. “Our second factory, which will come into operation in 2023, will have a further 1.5GW capacity. So, our UK production will be about 2.5GW by 2024. We've also got funding for 2.5GW for overseas, but we haven't announced where that will be.”
In PEM electrolysis, a membrane is used as the medium, which has a “tremendous advantage” over a wet, caustic electrolyte, according to Purkess: “The electrochemistry is very quick and can be ramped up and down in under two seconds, from 20%-100%, that's important for the electricity grid in terms of managing power.”
Renewable energy is difficult to schedule, especially in the UK, where the wind might blow, or it might not. “The electricity network has to be perfectly balanced on supply and demand to maintain frequency,” Purkess adds. “If demand doesn't match the input from the wind, for example, we have to turn off wind turbines. That’s called curtailment; we're not utilising the renewable energy that could be being generated, and that affects all our bills. Electrolysis enables us to harvest that surplus electricity and convert it into hydrogen, maintaining the balance in an economical way.”
Rival producer CPH2, however, has pioneered a patented, proprietary process which doesn’t use a membrane but is said to be just as fast as PEM, and produces hydrogen and medical-grade oxygen.
Optimism
Although the industry is optimistic that the UK can achieve its hydrogen production targets, both in the short term and by the end of the decade, but key figures raise warnings too.
Greaves says: “As far as the work the government is doing, it’s definitely a positive step in the right direction. Speed is of the essence, because there's very little hydrogen around; we need to scale that up quickly.
“There’s been a very strong focus from government on the supply side, but the idea of ‘build it and they will come’ is not necessarily rooted in reality. We think there's a very important counterbalance which is to make sure we're supporting the demand side as well, making sure we're feeding in what we need at the bottom: the skills, the supply chain, the framework, the codes and standards. There's lots to be done, but the industry’s enthusiastic to get started.”
Purkess adds: “The challenge for the UK is to ensure it retains companies like ITM that are at the cutting edge of enabling us to meet net zero. The manufacturing could drift overseas, so we need big projects to take off in the UK quickly.
“There’s a danger the government is distracted by blue hydrogen due to lobbying by fossil fuel companies. In terms of project viability, costs and lead times, you're more likely to get a very large green hydrogen project going much quicker and at cost than a blue hydrogen project.
That, says Purkess, is a very risky venture. “There's a lot of liability and cost for storing that carbon dioxide forever, and you’re still at the mercy of fossil fuel prices; it doesn't make sense. “For energy security, food security, balance of payments, exports, manufacturing jobs, you name it, Britain needs to start applying very large green hydrogen projects.”
Duffy agrees: “We have a hydrogen strategy that is written for blue hydrogen, not green, and it’s almost saying: ‘We're still going to have a lot of carbon dioxide that we're going to have to bury at some stage, so let's put the money into burying the problem rather than solving the problem’. The ambition is a little bit low, for want of a better word. But we’ll do it; we just need to be more ambitious.”
BOX: One step closer to zero-emission commercial aviation
Airbus has an ambition to develop the world’s first zero-emission commercial aircraft by 2035. Its ZEROe multi-year demonstrator programme, based on an A380 fuselage, has now officially taken off, with the objective to test a variety of hydrogen technologies both on the ground and in the air.
The ZEROe demonstrator will now be the next to test zero-emission technologies. It will carry four liquid hydrogen tanks as well as a hydrogen combustion engine mounted along the rear fuselage. The distribution system will feed liquid hydrogen into a conditioning system in which it will be converted into its gaseous form before being introduced into the engine, where it is combusted for propulsion.
“This isn’t Airbus’ first experience with hydrogen-powered flight,” says Mathias Andriamisaina, Airbus ZEROe demonstrator leader. “From 2000 to 2002, Airbus was a key partner in the European Union’s Cryoplane research project. Building on these academic inquiries, we’re proud to take the testing of hydrogen combustion to the next level.”
The hydrogen combustion engine is a key part of the ZEROe demonstrator programme, and involves other partners too. CFM International, a joint venture between GE and Safran, is set to develop the hydrogen combustion engine and prepare it for testing. Specifically, the company will modify the combustor, fuel system and control system of a GE Passport turbofan to run on hydrogen. The engine was selected due to its physical size, advanced turbo machinery, and fuel flow capability.
Each technology component – the hydrogen tanks, hydrogen combustion engine and liquid hydrogen distribution system – will be tested individually on the ground. Then, the complete system will be tested first on the ground and then subsequently in flight. The first flight is expected to take place in the next five years.