Chennai: The technology used to produce green hydrogen plays a decisive role in determining how clean the fuel actually is, even when renewable energy powers the process, according to a new study by researchers at IIT Madras. The findings show that while some hydrogen-production systems may generate higher emissions during manufacturing, they can deliver significantly cleaner hydrogen over their lifetime due to greater durability and efficiency.
The study, conducted in collaboration with the Centre for Study of Science, Technology and Policy (CSTEP) and published in Energy & Fuels, examines proton-exchange membrane (PEM) electrolysers, which split water into hydrogen and oxygen using electricity.
Researchers found that improving certain PEM electrolyser components—such as applying specialised coatings to internal plates—enhances performance and lifespan. Although these modifications raise emissions at the manufacturing stage, the overall environmental footprint is reduced because the systems operate longer and produce cleaner hydrogen over time. The study underscores the importance of evaluating technologies across their entire life cycle rather than focusing solely on upfront emissions.
“Our research offers a roadmap for scaling up green hydrogen in India. By analysing the environmental and material impacts of different technologies, we can make informed choices that balance efficiency with sustainability,” said Prof Satyanarayanan Seshadri of IIT Madras’ department of applied mechanics and biomedical engineering. He added that the findings highlight the crucial link between technology selection and environmental outcomes for policymakers and industry.
Peter Waiyaki, a research scholar at IIT-M, noted that PEM electrolysers are more efficient than conventional alkaline systems and better suited for large-scale hydrogen production.
India has pledged to reach net-zero emissions by 2070 and source 50% of its electricity from non-fossil fuels by 2030. Green hydrogen is expected to play a key role in cutting emissions from hard-to-abate sectors such as industry, transport and buildings, while also strengthening energy security. The National Green Hydrogen Mission, launched in 2023, targets annual production of five million metric tonnes of green hydrogen by 2030 and aims to boost domestic electrolyser manufacturing.
