19th June 2025
Yesterday I noted that natural gas (ie methane) produces less carbon dioxide when burnt than either coal or oil. Hydrogen, when that is burnt, produces no carbon dioxide only water. Is hydrogen the green fuel of the future?
Hydrogen is the simplest and most abundant element in Earth but it rarely exists as a gas, instead being found joined with other elements – eg with oxygen which produces water. It can occasionally be found underground but as there are seldom viable ways of extracting, scientists instead have developed ways of producing hydrogen gas artificially – depending on the process used, a number of artificial hydrogens are available, including grey hydrogen, blue hydrogen and green hydrogen.
Grey hydrogen is made using a process called steam reforming, which brings together natural gas and heated water in the form of steam. As well as hydrogen this process also produces carbon dioxide.
Blue hydrogen uses the same process, but aims to avoid the problem of carbon dioxide emissions by capturing the CO2. As reported previously CCS is costly and not necessarily that efficient.
Green hydrogen uses electricity to split water into its component elements of hydrogen and oxygen. This reaction does not produce CO2 but depending on the supply of the electricty, there may be carbon emissions that form part of the total production. The significant criteria would be the use of renewable electricity.
In Scotland Shell* has been partnering with others in the Acorn project which includes the production of blue hydrogen from natural gas with carbon dioxide being stored under the sea via disused pipelines. (1) This involves substantial investment, including government subsidises. The BBC has reported: “UK Energy Secretary Ed Miliband has confirmed that £200m will be provided to progress the Acorn Carbon Capture and Storage (CCS) scheme in Aberdeenshire.” (2)
“The European Commission is facing calls to assess the climate impact of scores of proposed hydrogen projects after data revealed that 90 percent of them could be used to prolong the use of planet-warming natural gas. Companies operating Europe’s existing natural gas infrastructure are seeking to preserve the value of their assets by converting them to carry clean-burning hydrogen to power homes and industry in line with legally-binding climate targets.
“But the data compiled by Brussels-based research and advocacy group Food & Water Action Europe, and shared with DeSmog, shows that 57 percent of 147 hydrogen projects under consideration by the European Commission are designed to also carry natural gas, or “blue” hydrogen made from the fossil fuel. A further 33 percent of projects have failed to rule out carrying fossil-based hydrogen, or have no credible plans to source climate-friendly “green” hydrogen.”
““Greenwashing must be fought, especially when it comes to using public money.”” (3)
- https://www.ten.com/sites/energies/files/2024-06/acorn-hydrogen-project-case-study.pdf
- https://www.bbc.co.uk/news/articles/cvgvx0xd16po
* Shell is, I think still involved with this project, but information is hard to come by. Shell did quietly withdraw from a similar on the Isle of Grain in Kent.
The Green Tau 