Unlocking the potential of green hydrogen in the UK

Hydrogen production is categorised by colour (see Figure 1). Grey hydrogen is the most common form as it uses natural gas to generate hydrogen through a process known as steam reforming. Blue hydrogen is the same process as grey hydrogen, with the carbon emissions then being captured through Carbon Capture and Storage(CCS). Of interest to us, green hydrogen is a zero-carbon fuel produced by using renewable energy to split water into hydrogen and oxygen via electrolysis(Figure 2). It has applications across power generation, industry, and transport.

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TheInternational Energy Agency states that it is possible to save 830 million tonnes of CO₂ annually through the reduction in fossil fuel energy use to generate hydrogen. Storage potential is the major advantage of green hydrogen. Unlike electricity, which often must be used immediately, hydrogen can be stored as a gas and converted back into power when needed. This flexibility helps counterbalance the intermittency of solar and wind generation. Hydrogen can also be used to decarbonise hard to abate sectors such as heavy transport, aviation and steel manufacturing, providing a pathway to reduce emissions where electrification is less feasible.

Furthermore, green hydrogen holds enormous cost reduction potential, with the price of electricity in generating green hydrogen through electrolysis representing around 70% of the cost of green hydrogen. Therefore, green hydrogen cost is expected to fall as renewable energy becomes more abundant and cheaper.

However, there are currently significant drawbacks of green hydrogen. With very high energy consumption needed to produce the fuel, 30-35% of energy used in generation of green hydrogen is lost in the electrolysis process. There are also safety issues because hydrogen is volatile and flammable.

On the 7^th April 2025, 27 hydrogen projects advanced to the next stage of the government’s flagship hydrogen programme. Hydrogen is said to help re-industrialise the UK’s manufacturing regions such as Teesside, a previous steelmaking area. With industry minister Sarah Jones singing hydrogen’s praises saying that ‘hydrogen can power our everyday life’ from ‘sustainable aviation fuel to public transport and clean energy generation’. Alongside these projects, there are further ambitious proposals for electrolytic production projects to generate green hydrogen close to offshore wind projects (Figure 3).

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Previous hydrogen trials in UK villages have been cancelled up until 2026, including the trial in Redcar in late 2023, due to concerns surrounding hydrogen supply. The UK government is committed to make a decision in 2026 on the role of hydrogen in home heating, with research currently ongoing.

Due to the challenges in storing and transporting hydrogen, alternative carriers like ammonia are gaining attention. There is already globally established literature that ammonia is safe and efficient for transporting hydrogen by ship. Green hydrogen is combined with nitrogen which is extracted from the air using an air separator. The ammonia when it arrives at its destination can then be split into hydrogen and nitrogen using an ammonia cracking process.

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PWC projects that demand for green hydrogen will grow at a moderate, steady pace until 2030, accelerating from 2035 onwards. For there to be a significant increase in the use of green hydrogen, there needs to be stronger research and development infrastructure alongside the development of green hydrogen skills in the workforce. As innovation accelerates and costs fall, green hydrogen is poised to become a cornerstone of the global transition to a low-carbon economy.