Hydrogen will play an “important role” in decarbonising heavy industry and transport, but a minor one in the heating of buildings, according to an analysis of more than 40 published hydrogen studies.
The meta-analysis, carried out by a consortium of German research institutes on behalf of the German government, finds that the use of hydrogen for decarbonisation “becomes unavoidable… when reaching a threshold of 80% GHG [greenhouse gas] reductions compared to 1990 [levels]”.
But hydrogen will provide only 4-11% of the final global energy consumption in 2050, with the main driver for climate neutrality being “a drastic decrease in final energy consumption by energy efficiency measures, and direct electrification”.
The actual ramp-up in hydrogen usage will be “country-specific, as it relies on national climate neutrality ambitions and already existing infrastructures”, says the study, entitled Future hydrogen demand: A Cross-sectoral, global meta-analysis.
The largest share for hydrogen and its derivatives in total energy demand will come from transport — including shipping and aviation — with studies giving a global median hydrogen share in final energy demand for the sector of 16%, but 28% in the EU.
The meta-analysis points out that hydrogen-powered fuel-cell road vehicles have a “well-to-wheel energy efficiency” of 34%, compared to 77% for battery electric vehicles — in other words, every 100kWh of input results in 34kWh and 77kWh on the road, respectively. But it adds that H2 can “potentially be a cost-efficient solution” for long-distance and heavy freight transport, due to the added weight of batteries and longer charging/refuelling times.
“More certainty for hydrogen demand in synthetic fuels can be found in the international aviation and maritime sectors,” it adds, due to a lack of competition from pure-electric solutions.
The report says that because many studies have not offered projections for the future use of hydrogen as a chemical feedstock, it can only provide aggregated figures for the use of hydrogen as an industrial heat source. Here, it gives the global median hydrogen share in the sector of 3%.
In terms of providing heating for buildings, there is the greatest similarity between studies, with a range of 1-2% of energy demand by 2050 in hydrogen-focused reports, but less than 0.5% in IPCC (Intergovernmental Panel on Climate Change) scenarios — giving a median hydrogen share of less than 2%.
“This bandwidth is small compared to the other sectors… indicating a relative certainty about hydrogen usage in this sector,” the meta-analysis explains.
“Arguments against hydrogen use in buildings are the availability of more suitable decarbonisation technologies,” it says. “The hydrogen value chain in the building sector is characterised by low overall efficiencies (eg, fuel cell heating 57%, hydrogen condensing boiler 64% compared to heat pumps with 300% or electric boilers with 95% efficiency).”
The report concludes: “Overall, hydrogen will thus play a significant role in climate change mitigation, but it will not be the dominant final energy carrier.
“Energy efficiency and direct electrification are generally seen as the main emission-reduction levers.
“Hydrogen therefore plays a relevant role in areas of application, where other technologies are technically or economically not feasible. While hydrogen therefore remains a theoretical option in all three demand sectors analysed, targeted policies are necessary to trigger an efficient use across sectors.”
The meta-analysis was funded by the German Federal Ministry of Education and Research, and is part of the HYPAT (H2 Potential Atlas) project, which is being led by Professor Martin Wietschel at the Fraunhofer Institute for Systems and Innovation Research (ISI) in Karlsruhe, Germany.
The full report can be downloaded here.