Hydrogen for road transport not economical, says new letter

Hydrogen for road transport not economical, says new letter


A group of international scientists have written an open letter to UK prime minister Boris Johnson to express their concerns about his government’s H2 strategy.

The experts, led by Cambridge University professor David Cebon, argue that rather than attempting to convert the existing gas grid to use hydrogen, an expensive and difficult proposition, the government should instead put its efforts into promoting electric heat pumps that are more efficient and can already deploy at scale today, supporting thousands of jobs.

“Hydrogen use for road transport is not efficient and does not make economic sense,” they wrote. “Hydrogen is a not an efficient energy source, which is a fundamental flaw when comparing it with other electrification alternatives.”

The letter argues that developing a green hydrogen industry “is vital — but only for things we can’t electrify.”

“The priority needs to be shifting away from fossil fuels towards efficient electricity-based heating and transport systems, while stimulating the use of green hydrogen for hard to electrify sectors such as steel, chemicals and possibly shipping.”

Grey hydrogen made from unabated fossil fuel should be replaced with the green variety “before considering other end-use sectors or blending hydrogen into the natural gas grid, which is now being done in a government-sponsored pilot project,” the scientists said.

“The UK alone produces around 700,000 tonnes of grey hydrogen a year, used to make fertiliser and to remove sulphur from oil. For every kilogram of grey hydrogen produced, the resulting CO₂ emissions are around 9kg, meaning grey hydrogen produces around six million tonnes of CO₂ annually in the UK,” the letter stated.

“Before considering markets that have existing electrification alternatives, or blending hydrogen into the natural gas grid, grey hydrogen needs to be urgently replaced with zero-emission green hydrogen made from wind and solar energy.”

The seven scientists also call upon the government to “take a cautious approach to blue hydrogen, avoiding lock-in to unsustainable fossil fuel infrastructure that could push net-zero out of reach.”

“By choosing to support blue hydrogen made from natural gas and CCS [carbon capture and storage], the UK must have stringent measures to assess the greenhouse gas emissions from the blue hydrogen manufacturing process and supply chain. Recent research from the US has highlighted the lack of understanding of the climate impacts of blue hydrogen, suggesting that these emissions can be as bad or even worse than simply burning natural gas.

“Assessing the lifecycle emissions of blue hydrogen is a complex issue that will involve auditing and possibly certifying hydrogen production plants, CCS facilities and most of the natural gas supply chain. This could take many years, when electric solutions like heat pumps and EVs are ready to deploy today.”

For more information visit www.cam.ac.uk

27th September 2021