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It could be the clean fuel of the near future - for homes and for heavy machinery.

Lord Bamford, head of JCB, is betting that it will power the next generation of emission-free tractors, diggers and loaders. Tom Heap meets the JCB team and discusses the pros and cons of hydrogen with climate scientist and Society Fellow Tamsin Edwards of King's College, London.

Listen now on BBC Radio 4


What our experts say

We asked Society Fellows Dr Katriona Edlmann, Dr Romain Viguier and Dr Ali Hassanpouryouzband from the University of Edinburgh and Mickella Dawkins from Loughborough University to offer some observations on the potential of maximising the production of green hydrogen for use as fuel in reducing carbon emissions. Their points take some of the themes of the programme a step further.


Dr Katriona Edlmann, Dr Romain Viguier, Dr Ali Hassanpouryouzband

Policy changes and carbon taxes are required to initiate the change to green hydrogen. BloombergNEF (BNEF) estimate that a carbon price of $50 per tonne of carbon dioxide (/tCO2) would be enough to switch from coal to clean hydrogen in steel making by 2050, $60/tCO2 to use hydrogen for heat in cement production, $78/tCO2 for making chemicals like ammonia, and $145/tCO2 to power ships with clean fuel, if hydrogen costs reach $1/kg. Heavy trucks could also be cheaper to run on hydrogen than diesel by 2031, although batteries remain a cheaper solution for cars, buses and light trucks.


What are the limiting factors?

Dr Katriona Edlmann, Dr Romain Viguier, Dr Ali Hassanpouryouzband

Current green hydrogen costs are:

  • Grey (no CO2 capture) $1-2/kg: established market price

  • Blue $2-3/kg: includes carbon capture storage (CCS) cost

  • Green $3-6/kg: higher price, which reflects early-stage project

BloombergNEF (BNEF) estimate a green hydrogen cost of $0.8 to $1.6/kg in most parts of the world before 2050.

These high green hydrogen costs are expected to reduce as:

  • Capital expenditure (capex) reduces with increases in production scale, learning rates, technology improvements and increased electrolyser system sizes. Siemens estimate the cost of electrolysers will come down from c.1000€/kW today to less than 500€/kW in the coming decade.

  • Efficiency is expected to improve to 70% in 2030. At the moment we need 1000 megawatts of electrolysis to produce 450 tonnes per day of green hydrogen.

  • Operation and management costs reduce following reductions in cost and experience on operation grows.

  • Input energy costs: the electricity cost is the largest cost associated with green hydrogen production so reduced renewable electricity cost is crucial. Offshore wind costs are already falling and will continue to do so, especially if hydrogen has dedicated renewable generation.

  • Reducing grid charges.

  • Load factors and flexibility improve to give more ramping up flexibility. Currently, they operate most efficiently at a given load which is a system constraint.


Mickella Dawkins

  • High production costs: green hydrogen is on average two to three times more expensive than hydrogen from fossil fuels (without carbon capture and storage). In addition, green hydrogen technologies for end uses can be expensive. Vehicles with fuel cells and hydrogen tanks cost at least 1.5 to 2 times more than their fossil fuel equivalent.

  • Energy losses: approximately 30-35% of the energy used to produce hydrogen through electrolysis is lost and there are energy losses at each stage of the green hydrogen value chain. The greater the energy losses, the more renewable energy capacity needed to generate green hydrogen. The main concern is whether the development of wind and solar will be swift enough to meet both the electrification and green hydrogen production demands and the cost of the additional capacity.  

  • No dedicated infrastructure: to date, hydrogen has always been produced close to where it is used. There’s a relatively trifling amount of hydrogen transmission pipelines and refuelling stations around the world.

  • Non-existent value recognition: there is no green hydrogen economy and no valuation of the abated greenhouse gas (GHG) emissions that green hydrogen can deliver. The lack of incentives and policies to promote the use of green hydrogen also limits demand.

  • How sustainable is grid electricity? Grid electricity may include electricity produced from fossil fuel plants, so any CO2 emissions associated with that electricity will have to be considered when evaluating the sustainability of the hydrogen produced from electrolysis.



What are the co-benefits?

Dr Katriona Edlmann, Dr Romain Viguier, Dr Ali Hassanpouryouzband

Apart from reducing our emissions, large scale green hydrogen production requires large scale transport and storage options to balance the variability in supply and demand needs over a year, or indeed for hydrogen export. 

The only way to provide the necessary scale of storage capacity for net zero is through geological storage, and re-purposing our existing gas fields for hydrogen is a sensible way to achieve this as we already know the rocks are suitable to securely store gas. This has the benefit of retaining our oil and gas skills, experience and jobs, and avoiding the huge decommissioning costs associated with stopping our natural gas offshore and pipeline network as they can be repurposed for hydrogen. There is a lot of research in these areas and the HyStorPor project team at Edinburgh University are leading the way in this research, looking at the feasibility of storing hydrogen in depleted gas fields. So far, all our research indicates it will be possible and there is a very useful briefing document that can be accessed for further information.


Mickella Dawkins

  • Employment/job creation

  • Contribute to energy security

  • Economic growth and rural development, especially in the Global South

  • Reduction in many air pollutants, e.g. reduction of emissions contributing to particulate matter exposure

  • The potential for additional system flexibility and storage, which supports further deployment of variable renewable energy



Are there any potential negative impacts of this idea?

Dr Katriona Edlmann, Dr Romain Viguier, Dr Ali Hassanpouryouzband, Mickella Dawkins

  • The need for freshwater as a feedstock for the electrolysis process may have negative impacts on local ecosystems and limit freshwater availability for other uses

  • Higher use of critical metals for solar PV and direct drive wind turbines for renewable energy generation

  • Hydrogen leakage during synthesis, storage, and use – hydrogen is an indirect GHG

  • Hazards associated with hydrogen leakage


Further reading


About the series

39 Ways to Save the Planet is a new radio series by BBC Radio 4 developed in partnership with the Society and broadcast in 2021. It showcases 39 ideas to relieve the stress that climate change is placing on the Earth. In each 15 minute episode Tom Heap and Dr Tamsin Edwards meet the people behind a fresh and fascinating idea to cut the carbon.

Programme website

Over the course of 2021, the Society will be producing events and digital content to accompany the series.

Episode 39: Hydrogen revolution

Listen now on BBC Radio 4


Featured card image: BBC

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