Newswise — The research bridges a void in our understanding regarding the climate impacts of hydrogen, a pivotal technology in the shift towards sustainable energy.
In contrast to emissions from the combustion of coal and gas, which include CO2, the combustion of hydrogen releases solely water vapor and oxygen. However, it is the leakage of hydrogen during its production, transportation, and utilization that contributes to the phenomenon of global warming.
While hydrogen itself is not considered a greenhouse gas, its chemical reactions within the atmosphere do impact other greenhouse gases such as methane, ozone, and stratospheric water vapor. Consequently, hydrogen emissions can contribute to global warming through indirect radiative effects, despite lacking direct radiative properties.
Dr. Maria Sand, a senior scientist at CICERO, spearheaded the study alongside her colleagues, who collaborated with researchers from the UK, France, and the US. The research received funding from the Research Council of Norway, with additional contributions from five industry partners in the hydrogen sector.
Sand emphasized that the climate impacts of hydrogen have been relatively understudied. Nevertheless, a limited number of papers, primarily relying on single model studies, corroborate the estimated global warming potential (GWP100) of 11.6 for hydrogen.
Sand explained that their research involved the utilization of five distinct atmospheric chemistry models to examine alterations in atmospheric methane, ozone, and stratospheric water vapor.
Sand highlighted the diverse interactions of hydrogen with various biogeochemical processes. Their estimates encompassed factors such as soil uptake, photochemical hydrogen production, the lifetimes of hydrogen and methane, and the intricate interplay between hydrogen and methane.
Thanks to the advanced and innovative utilization of existing climate models, the study represents the most comprehensive evaluation of the climate impact of hydrogen conducted thus far. It stands as a significant milestone in our understanding of the subject.
Sand emphasized that they have thoroughly evaluated the uncertainties associated with their findings, ensuring that their study provides a solid and reliable foundation for making informed policy decisions regarding hydrogen.
Sand emphasized the significance of the global warming potential of 11.6 attributed to hydrogen, highlighting the clear importance of minimizing hydrogen leaks. Although currently lacking the necessary technology to effectively monitor and detect such leaks on a large scale, the industry is actively developing new technologies as part of its adaptation process.
The potential advantages of transitioning to a hydrogen economy will be contingent upon two key factors: the magnitude of hydrogen leakages and the extent to which hydrogen can replace fossil fuels. Achieving significant benefits will rely on minimizing leakages and maximizing the substitution of hydrogen for traditional fossil fuel sources.
Sand expressed that despite the progress made, there remain numerous unanswered questions regarding hydrogen's climate effects. Their research group is committed to further expanding their knowledge to ensure that decision-making regarding this crucial mitigation technology is both timely and well-informed.
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