The world is scrambling to build a new clean energy system, and considerable hype is being devoted to the possibilities of hydrogen: a colourless, energy-dense gas that produces only water vapour when burnt. This week, the final agreement at Cop28 referenced “low-carbon hydrogen production” as a key technology that needs to be deployed for the world to reach net-zero emissions.
The UK government has also announced 11 major new hydrogen production projects, which are to be backed by £2bn of government funding over the next 15 years.
Hydrogen is widely touted as a “missing link” to decarbonise difficult sectors such as steel, shipping, and chemicals production. The International Energy Agency anticipates that global hydrogen demand would increase six-fold if emissions were to be brought to net zero. Low-carbon hydrogen is usually produced either by the electrolysis of water using renewable electricity (“green” hydrogen), or from natural gas coupled with carbon capture and storage technology (“blue” hydrogen).
The world’s major economies all have massive programmes in place with the aim of becoming the leader in the hydrogen industry. The EU’s REPowerEU programme is aiming for ten million tonnes of renewable hydrogen production by 2030. The US is targeting an industry worth $140bn in revenues and 700,000 jobs by 2030. The UK’s target of 10GW hydrogen production by 2030 would consume the equivalent of half of the country’s planned offshore wind capacity.
Behind these big policy packages lies massive corporate lobbying. The hydrogen industry is infamous for being pushed by fossil fuel companies. Critics argue they do so to have an excuse to keep developing natural gas infrastructure: blue hydrogen in particular, it is said, is used as a justification for companies to continue extracting natural gas.
Analysis from the American NGO Open Secrets has found that oil and gas companies including Shell, BP, Chevron and ExxonMobil have all been lobbying on hydrogen matters. Another analysis from Corporate Europe Observatory found that the EU hydrogen lobby – whose main players are fossil gas companies – spend an annual figure of just shy of €60m.
Lobbyists nonetheless outwardly argue that hydrogen can be a “clean” fuel for the future. But new science suggests that there are climate concerns around even green hydrogen, which has no link to fossil fuel production, should it leak into the atmosphere during production, transport or at storage sites.
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A study produced by climate scientists at the Oslo-based CICERO Centre for International Climate Research has found that leaked hydrogen has a warming effect around 12-times greater than emitted CO2. This is because hydrogen has a significant amplifying effect on the warming impact of certain greenhouse gases, such as methane and ozone, even though it is not itself a greenhouse gas.
“We used five different atmospheric chemistry models and investigated changes in atmospheric methane, ozone and stratospheric water vapour,” said Dr Maria Sand, a senior scientist at CICERO, who led the study. “A global warming potential of 11.6 is significant, and our study clearly shows the importance of reducing hydrogen leaks.”
“Reducing hydrogen leaks” makes sense in theory, as it will save producers money. But in practice, it is complicated by the fact that hydrogen molecules are much smaller and lighter than those of natural gas, and as a result are harder to contain.
There are also no readily available tools for measuring just how significant hydrogen leaks are; even more established systems for monitoring methane keep vastly underestimating the scale of leakages. But a report from the UK think tank Green Alliance offers some estimates: hydrogen heating tests have found that leakage is around 1.2 to 3 times greater than is the case with natural gas, while researchers at Columbia have forecast standard leakage rates of 3 to 6 per cent.
Modelling from Green Alliance has found that even a leakage rate of a few percentage points could massively reduce the climate benefits of hydrogen, as the below graphic illustrates.
How worried should we be by studies such as this? According to experts interviewed by Spotlight, very.
“It is definitely deeply concerning. Hydrogen is extending the lifetime of methane in the atmosphere, and methane is a hugely damaging greenhouse gas that is 80 times more potent at warming than carbon dioxide,” says David Schlissel, from the Institute for Energy Economics and Financial Analysis (IEEFA). “This is a critical issue. We cannot go down a path now of spending hundreds of billions on a new energy system that may well accelerate climate change.”
Colm Britchfield, from the climate think tank E3G, adds that research such as this shows that leaked hydrogen could have a “hugely damaging effect”, and as a result should not be deemed a “cure-all” for all our energy transition needs, particularly where it would need to be transported by pipelines over long distances.
Britchfield adds that the fact that climate impacts of hydrogen have gone unreported on a policy level is indicative of how some of the gas companies pushing hydrogen do not necessarily care if the fuel works or not as a low-carbon alternative. “Some of the companies pushing hydrogen – particularly for heating – have no essential interest in being right about hydrogen, or about the hydrogen bet paying off,” he says. “Their main interest is simply to try and keep fossil fuel investment, and gas grid investment, where it is.”
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