Blue hydrogen 'hard to justify on climate grounds', US study warns

Campaigners are urging the UK government to prioritise and support the production of 'green' hydrogen made using renewable energy, after a major US academic study today found that 'blue' hydrogen produced using fossil fuels could be worse for the climate than burning natural gas.

The study, led by researchers at Cornell and Stanford universities, claims to be the first to peer reviewed analysis to assess the lifecycle emissions of so-called blue hydrogen that manufactures hydrogen from fossil fuel gas and then captures the resulting emissions. It concludes that "there really is no role for blue hydrogen in a carbon-free future".

Blue hydrogen is currently being supported by the UK and several other governments around the world as a potentially key source of the versatile low carbon fuel.

It also has the backing of UK gas network firms and oil and gas giants such as Shell and BP, the latter of which last week signed a flurry of prospective deals to take fuel produced at a major new blue hydrogen and CCS facility it is currently developing in Teesside.

However, today's study estimates that emissions from the production - rather than the use - of blue hydrogen "are quite high", and that resulting greenhouse gas emissions, including both CO2 and methane, are "more than 20 per cent greater than burning natural gas or coal for heat, and some 60 per cent greater than burning diesel oil for heat".

"Our analysis assumes that captured carbon dioxide can be stored indefinitely, an optimistic and unproven assumption," the study concludes. "Even if true though, the use of blue hydrogen appears difficult to justify on climate grounds."

Robert Howarth, co-author of the study and Professor of ecology and environmental biology at Cornell University in New York, said the research showed that public funds should only be invested in green hydrogen if government's want to use hydrogen to support their net zero ambitions.

"Politicians around the world, from the UK and Canada to Australia and Japan, are placing expensive bets on blue hydrogen as a leading solution in the energy transition," he said. " Our research is the first in a peer-reviewed journal to lay out the significant lifecycle emissions intensity of blue hydrogen. This is a warning signal to governments that the only 'clean' hydrogen they should invest public funds in is truly net zero, green hydrogen made from wind and solar energy."

The study, published in the journal Energy Science & Engineering, has been seized on by campaigners as part of a growing battle over the production of hydrogen in the UK, with the versatile fuel seen as a critical tool to helping decarbonise a raft of industries and processes.

While 'green' hydrogen is widely accepted as the most climate-friendly form of the gas, as it can be produced using renewable electricity via a process known as electrolysis to separate water into its component parts of oxygen and hydrogen, it is at present relatively expensive and requires significant scaling of manufacturing capacity in the UK.

So called 'blue' hydrogen is seen by some as a potential alternative, although unlike green hydrogen not all CO2 can be cut from the production process. Critics argue that as it is produced from methane and requires carbon capture and storage (CCS) technologies to be installed the approach will ultimately prove more expensive than green hydrogen production. As such green campaigners fear blue hydrogen is being used as a "Trojan horse" to continue justify investment in fossil fuel exploration.

At present hydrogen resources are scarce, and demand for hydrogen to help decarbonise a raft of sectors - from aviation and heavy trucks to steel and cement production and even home heating - is likely to surge in the coming years, raising questions about which sectors are most in need of H2.

Climate campaigners argue green hydrogen production should be prioritised, and largely used in hard to decarbonise sectors such as steel, cement, shipping and aviation. But UK gas companies have argued hydrogen should also be used for home heating and cooking as a replacement for methane in the gas grid.

Juliet Phillips, senior policy advisor for the clean economy at climate think tank E3G, said today's latest study demonstrated that blue hydrogen derived from fossil fuels "is far from a truly zero emissions fuel".

"There is no time left to waste in second rate solutions to the climate emergency," she said. "Worryingly, the UK government has so far allocated around 75 per cent of public investments in hydrogen towards this fossil-based fuel. We encourage the UK government to rethink its risky strategy of pursuing a 'twin track' approach of supporting both blue and green hydrogen, and instead focus on becoming a global leader in green hydrogen sourced from renewables."

The government is expected to shortly publish its long awaited Hydrogen Strategy, setting out how it intends to help scale the nascent sector towards reaching its current targets for 5GW of hydrogen production capacity by the end of the decade, which it estimates could deliver 8,000 jobs by 2030.

However, a government spokesperson insisted "low carbon hydrogen" or could play a key role in the UK's climate change, citing analysis from the Climate Change Committee suggesting a mixture of green and blue hydrogen would be consistent with delivering net zero emissions.

As part of the Hydrogen Strategy the Department for Business, Energy and Industrial Strategy (BEIS) also said it planned to consult on a new UK standard for low carbon hydrogen production "to ensure the technologies we support make a real contribution to our goals".

"Low carbon hydrogen will be essential for meeting our legally binding commitment to eliminating the UK's contribution to climate change by 2050, with more details to be set out in our forthcoming Hydrogen Strategy," BEIS said in a statement.

It follows a study earlier this week led by the public-private Zemo Partnership - formerly LowCVP - and consultancy Element Energy which assesses the range of potential routes for using hydrogen to help deliver a net zero transport system.

The study - which included input from Shell, Cadent Gas, Advanced Biofuels Solutions, and several gas network firms - looks at both green and blue hydrogen production, as well as the potential for distribution, carbon capture and storage, and various different uses for the fuel across the transport and buildings sectors.

It found that green hydrogen produced via renewables-powered electrolysis represented one of the lowest emissions pathways in the medium term, and that there is likely to be a wide variation in the CO2 associated with each of the alternative pathways, depending on the carbon footprint of the energy and feedstocks used.

Zemo Partnership's head of sustainability, Gloria Esposito, said deivering on the UK's net zero emissions goals was "far from simple, requiring an innovative range of low and zero carbon technologies".

"Our work shows that hydrogen could be a key option but policy will need to incorporate full consideration of the energy consumed by low carbon fuel supply chains if we are to achieve future climate goals," she added.