Reframing hydrogen’s role
Duncan Matthews of MaREI argues that while enthusiasm for further green hydrogen development has cooled, failing to plan for its potential role could create costly inefficiencies in the energy transition.
Duncan Matthews asserts that “hydrogen was the cool kid on the block for a brief period”, but that momentum has been lost. This loss of momentum, he explains, was a key motivation behind his research at University College Cork, where he has explored how we model hydrogen and its potential role in deep decarbonisation scenarios.
Despite this change in sentiment, Matthews emphasises that the underlying case for hydrogen has not disappeared. “Current research points to an important role for hydrogen,” he states, particularly “in the hard to abate sectors in deep decarbonisation scenarios”.
These sectors, where electrification alone is insufficient, remain central to achieving climate targets aligned with limiting warming to 1.5 degrees Celsius or 2 degrees Celsius. Matthews stresses that hydrogen’s relevance in these contexts is consistently identified in global modelling.
He also highlights that hydrogen is already a significant emissions source. “Hydrogen today accounts for about 2 per cent of our current emissions globally,” he says.
“While this may seem small, that is roughly equivalent to the emissions of the aviation industry.”
“The question is not whether hydrogen has been overhyped, but what happens if the wolf shows up.”
The ‘boy who cried wolf’ effect
Hydrogen development has undergone a ‘heap cycle’ model, whereby this there is a technology trigger. “Technologies begin with a technology trigger, followed by a peak of inflated expectations. When these expectations are not met, they fall into a trough of disillusionment before eventually stabilising.”
Contextualising that this has taken place on three occasions, the 1970s, early 2000s, and 2022, Matthews warns of the consequences of this pattern.
“We have had repeated false alarms that have not materialised, and this can be described as the boy who cried wolf effect. As a result, we are going to lose confidence, we are going to lose faith, we are going to lose interest. This is understandable, but it may lead to under-preparation.
“We are still faced with 2 per cent of emissions in the hard to abate sectors. The question is not whether hydrogen has been overhyped, but what happens if the wolf shows up.”
Testing the risk
To explore this, Matthews developed a set of scenarios using energy system modelling at UCC, drawing on projections from the Intergovernmental Panel on Climate Change.
The first scenario assumes proactive planning. “We have perfect foresight and, on that basis, we design a system that optimally meets those needs,” he explains.
The second is a reactive approach: “We focus all our efforts on electricity, we kind of forget about hydrogen, and then we tack it on at the end.”
The third scenario reflects growing scepticism. “If we have grown sceptical of you as a technology, you need to do it on your own,” he says, describing a system where hydrogen is prevented from integrating with the power sector.
Higher costs
The results highlight the risks of delayed or restrictive planning. In the reactive scenario, Matthews finds that costs are “about 10 to 14 per cent more expensive”, depending on demand levels. This reflects inefficiencies created when hydrogen infrastructure is added after electricity systems are already fixed.
The isolated scenario produces a much sharper increase. “Very strikingly, refusing to allow electrolysis to couple into the power sector yielded a 33 to 41 per cent more expensive system,” he says.
He explains that this is driven by duplication of infrastructure. “You have got capacity duplication there, particularly in areas such as battery storage, which could otherwise be shared across the system.”
Sector coupling
A significant theme in Matthews’ analysis is the importance of integration between hydrogen and electricity systems. “If we can manage our concerns around upstream emissions and cost impacts, sector coupling can yield a lot of system efficiencies,” he says.
This involves allowing electrolysis (the process used to produce hydrogen from electricity) to interact with the power system. However, Matthews acknowledges that concerns about affordability and emissions are valid. He suggests that the challenge is to address these concerns without blocking integration entirely.
Matthews says that there must be a renewed emphasis on hydrogen development, in spite of current cost challenges and the loss of momentum.
“Negating to proactively plan for it will yield a more expensive system if a significant role does emerge,” he concludes.
