Blue hydrogen rubbished

A paper from Robert Howarth & Mark Jacobson, from, respectively, Cornell and Stanford University, rubbishes the proposed use of blue hydrogen. They say that, with methane emissions taken into account, blue hydrogen, that is hydrogen gas produced by steam reformation of fossil gas with Carbon Capture and Storage (CCS), would be worse (by 20%) in climate emission terms than using natural gas (NG) or even coal as a fuel option. They claim that ‘the small reduction in carbon dioxide emissions for blue hydrogen compared with natural gas are more than made up for by the larger emissions of fugitive methane’. Given that, and also the uncertainties about the effectiveness of CCS, they concluded that ‘the use of blue hydrogen appears difficult to justify on climate grounds’.

That conclusion led to a critique by Matteo Romano, from Milan Polytechnic, along with 23 other mostly European authors, who claimed that the analysis was flawed and overstated the emissions, and that it was ‘possible for blue hydrogen to have significantly lower equivalent CO2 emissions than the direct use of NG, provided that hydrogen production processes and CO2 capture technologies are implemented that ensure a high CO2 capture rate, preferably above 90%, and a low-emission NG supply chain’.

This critique produced a dismissive reaction from Howarth & Jacobson, who said that its analysis ‘derives from a cartoon and hypothetical guesses, not scientific data’- the cartoon, they noted, being ‘on a web site from an oil and gas industry trade group’. Instead, they provided chapter and verse on the fugitive gas emission issue, and based on real world data, rather than hypothetical projections, reasserted that ‘there is no room for blue hydrogen in a decarbonized energy future’. 

In a Linkedin riposte, Romano, writing personally, disagreed, and, although accepting that there were methane leakage issues, said ‘it is time to break the renewables vs. CCS polarization’. Well, perhaps that is the central issue in strategic terms. We can argue about the blue hydrogen/methane emissions data and the prospects for improving SMR and CCS performance, but why are we trying to use fossil gas anyway?  What’s wrong with heading for zero carbon green hydrogen produced via electrolysis using renewable power?  Are we saying that it will be too expensive, or that there won’t be enough of it? That sort of projection is already looking dubious- and not just because fossil gas prices are accelerating due the Russia’s attack of Ukraine. Green hydrogen costs are falling fast, with new technology emerging.  Surely that’s the way to go, not trying to stay with fossil fuel? 

However it’s a matter of timescale. In their initial paper, Howarth and Jacobson say that ‘the supply of green hydrogen in the future seems limited for at least the next several decades’. But they do not see any reason for converting natural gas to blue hydrogen- that would lead to more emissions than just using gas direct.  Mind you, you could say the same sort of thing in relation to the economics of green gas- that will always be more expensive than the renewable power used to make it. It may often be better to use the renewable power direct, although there is the storage issue. Green gas can be easily stored, unlike green electricity. 

So what’s the bottom line? Howarth and Jacobson conclude that ‘society needs to move away from all fossil fuels as quickly as possible, and the truly green hydrogen produced by electrolysis driven by renewable electricity can play a role. Blue hydrogen, though, provides no benefit. We suggest that blue hydrogen is best viewed as a distraction, something than may delay needed action to truly decarbonize the global energy economy, in the same way that has been described for shale gas as a bridge fuel and for carbon capture and storage in general’.

For his part, Romano does actually say, in his Linkedin comments, that he sees renewables as central: ‘Decarbonization of our economy should primarily proceed through quick deployment of renewables and on electrification. The substitution of the existing fossil-based power generation with renewables and the electrification of heat production and mobility should be THE priorities in the energy transition,’ while ‘CO2 capture and storage will have a minor role in the power sector’. 

However, he does, nevertheless, see some role for blue hydrogen and argues that, ‘producing large amounts of green hydrogen in the short-term involves subtracting the still scarce renewable electricity to its direct use to displace fossil-based power generation, to produce low temperature domestic and industrial heat and in the mobility sector, where the decarbonization potential is higher at lower cost. In this context, blue hydrogen will allow decarbonizing some sectors in the short period, while penetration of renewables and electrification (whose speed of deployment is the bottleneck for decarbonization) proceed’.

So they still have differing views. Romano seems to be convinced that renewable deployment will be constrained, and you could say that might indeed be the case if blue hydrogen is given its head. In their initial paper, Howarth and Jacobson make the political point that there are commercial pressures for that. They say ‘much of the push for using hydrogen for energy since 2017 has come from the Hydrogen Council, a group established by the oil and gas industry specifically to promote hydrogen, with a major emphasis on blue hydrogen’, and they claim that ‘ from the industry perspective, switching from natural gas to blue hydrogen may be viewed as economically beneficial since even more natural gas is needed to generate the same amount of heat.’

The blue hydrogen band-wagon certainly continues to roll on, although, as I reported in an earlier post, there are doubts about whether the very high carbon capture rates sometimes claimed are viable, much less secure long term storage. Howarth and Jacobson stress that their analysis ‘assumes that captured carbon dioxide can be stored indefinitely’, which they see as ‘an optimistic and unproven assumption’. And they say, even given that assumption, it is hard to justify the use of blue hydrogen on climate grounds, and that, overall, ‘there is no way that blue hydrogen can be considered ‘green’.’