Groundbreaking University of Sheffield Study Exposes Green Hydrogen Sustainability Challenges

The University of Sheffield's latest research has cast a critical light on the sustainability of green hydrogen, a fuel hailed as a cornerstone of the global net zero transition. Published in Nature Communications Sustainability on 13 February 2026, the study titled "Sustainability of green hydrogen technologies depends on energy mix and supply chain" warns that without rapid energy grid decarbonisation and a complete supply chain overhaul, green hydrogen risks failing as a truly sustainable alternative to fossil fuels. Led by Professor Lenny Koh from the Sheffield University Management School and Dr Moein Shamoushaki, the findings underscore the urgent need for aligned policies to ensure green hydrogen delivers on its promise.

Currently, around 96 per cent of hydrogen production relies on fossil fuel-based electricity, making even 'green' variants environmentally questionable. The research highlights how national energy mixes and international supply chains will determine whether green hydrogen reduces emissions or merely shifts them elsewhere. For the United Kingdom, positioned as a potential production hub, these insights are particularly timely amid ambitions to scale low-carbon hydrogen production.

What is Green Hydrogen and Why Does It Matter?

Green hydrogen is produced through electrolysis, where water (H₂O) is split into hydrogen (H₂) and oxygen (O₂) using electricity from renewable sources like wind or solar power. This process contrasts with 'grey' hydrogen, made from natural gas via steam methane reforming, which emits significant CO₂. The appeal of green hydrogen lies in its versatility: it can decarbonise hard-to-abate sectors such as steelmaking, heavy industry, aviation, and shipping, where batteries fall short.

In the UK context, the government's Hydrogen Strategy targets up to 10 gigawatts (GW) of low-carbon hydrogen production capacity by 2030, potentially creating thousands of jobs in regions like South Yorkshire, home to the University of Sheffield. However, the Sheffield study reveals that sustainability hinges on clean electricity inputs; fossil-heavy grids undermine the entire lifecycle.

The Methodology Behind the Sheffield Analysis

Researchers employed a prospective life cycle assessment (LCA) framework using OpenLCA software and the ReCiPe 2016 midpoint method. They modelled 20 international green hydrogen supply chain (IGHSC) scenarios across 14 leading hydrogen nations: UK, USA, China, Japan, France, Norway, Canada, Germany, South Korea, Austria, Ireland, Poland, Italy, and the Netherlands. Projections spanned 2023 to 2050, incorporating energy mix evolutions from the International Energy Agency (IEA).

Five production technologies were evaluated: three electrolysis types—alkaline electrolysis (AEL), proton exchange membrane (PEM), and solid oxide electrolysis (SOEL)—plus two biomass methods: gasification (BG) and dark fermentation (DF). Impacts focused on global warming potential (GWP in kg CO₂ eq/kg H₂), marine eutrophication (ME), stratospheric ozone depletion (SOD), and human toxicity (HT). Scenarios varied manufacturing locations, export/import flows, and operational phases like raw material extraction, assembly, operation & maintenance (O&M), storage, and transport.

This rigorous, spatial-temporal approach revealed phase-specific burdens: O&M dominated electrolysis GWP (up to 78 per cent), while manufacturing led in biomass systems.

Key Findings: Emissions Reductions Not Guaranteed

In 2023, electrolysis scenarios showed higher GWP than biomass due to dirty grids powering energy-intensive processes—PEM3 reached 18.21 kg CO₂ eq/kg H₂. By 2050, PEM electrolysis could slash GWP by 97 per cent to 0.38 kg CO₂ eq/kg H₂ in optimal cases, outpacing biomass's 69 per cent drop. Yet, slower decarbonising nations like China (net zero by 2060) lagged, with supply chains involving them retaining elevated impacts.

PEM Scenario 4—UK manufacturing with 50 per cent exports to the USA—emerged as the most sustainable across all metrics, benefiting from the UK's projected 2050 grid decarbonisation. Rankings via TOPSIS-fuzzy multi-criteria decision analysis confirmed electrolysis's grid sensitivity versus biomass's feedstock reliance.

Country Comparisons Highlight Energy Mix Criticality

Norway's renewable-heavy grid made it ideal for electrolysis hubs, while Poland and Italy's fossil dependencies yielded poorer outcomes. The UK and USA duo in PEM4 exemplified synergy: UK production leverages maturing renewables, exporting to bolster US resilience. China-sourced chains underperformed due to coal persistence, emphasising geopolitical supply risks.

For UK academics, this validates Sheffield's role in energy research, aligning with the Energy Institute's focus on hydrogen innovation.

Photo by Jason Lee on Unsplash

UK's Strategic Position in Green Hydrogen Production

The UK stands poised as a green hydrogen leader, per the study. With grid decarbonisation on track for 2050 and projects like the HyNet North West cluster advancing, domestic PEM manufacturing could cut supply chain emissions dramatically. Government allocations via the £240 million Hydrogen Allocation Round support electrolyser deployment, but grid constraints—National Grid connection queues exceed 400 GW—pose hurdles.

Sheffield's proximity to industrial heartlands amplifies its contributions; Professor Koh's team advocates policy alignment to exploit these advantages. Explore university opportunities in the UK for energy researchers.

Supply Chain Overhaul: From Manufacturing to End-Use

Electrolysers' production, often in Asia's coal-powered factories, contributes 20-30 per cent to lifecycle emissions. The study urges reshoring or greening manufacturing, alongside low-carbon transport like hydrogen carriers (e.g., liquid organic carriers). Storage and end-use phases add 10-15 per cent impacts, necessitating efficient pipelines and blending.

Statistics reveal challenges: global electrolyser capacity must scale 100-fold by 2030, per IEA, demanding sustainable rare earth sourcing for PEM membranes.

Policy Recommendations and Solutions

Professor Koh stresses: "Aligning green hydrogen technology selection with regional decarbonisation trajectories is crucial." Policymakers must prioritise grid upgrades, incentives for clean manufacturing, and international standards. UK's refreshed Hydrogen Strategy (due autumn 2026) could incorporate LCA mandates for projects.

Solutions include hybrid grids with dedicated renewables for electrolysis and biomass co-location for feedstock security. Dr Shamoushaki adds: "Delays in renewable deployment could substantially alter sustainability." For actionable insights, see the full study DOI: 10.1038/s44458-025-00033-3.

Expert Insights from University of Sheffield Leaders

Professor Lenny Koh, a global authority on sustainable supply chains with over 200 publications, directs Sheffield's Advanced Resource Efficiency Centre (AREC). Her interdisciplinary work spans EPSRC-funded low-carbon projects worth millions, positioning Sheffield at the forefront. Co-author Dr Shamoushaki, a Research Associate, brings LCA expertise to energy transitions.

Sheffield's Management School fosters such innovation, offering PhD programs in operations for net zero. Read more on crafting an academic CV for research roles.

Implications for Net Zero and Hard-to-Abate Sectors

Green hydrogen could abate 10 per cent of energy emissions by 2050, per IEA, but only with clean chains. UK's steel (e.g., Port Talbot) and chemicals stand to benefit, creating 80,000 jobs. Risks include stranded assets if grids lag, amplifying Sheffield's call for urgency.

Stakeholders—from government to industry—must collaborate, mirroring Sheffield's consortia models.

Photo by Michele Wales on Unsplash

Career Opportunities in Green Hydrogen Research

The sector's growth spurs demand for experts in LCA, supply chain management, and energy engineering. UK universities like Sheffield lead with funded PhDs (e.g., hydrogen sealing via Leonardo Centre) and postdocs. Roles span research assistant jobs, lecturing, and industry partnerships.

• PhD in sustainable hydrogen supply chains
• Research Associate in Energy Institute projects
• Lecturer in Operations Management for net zero

Check higher ed jobs for openings. Sheffield's networks, like UK-HyRES Hydrogen Hub, offer early-career pathways.

Future Outlook: Pathways to Sustainable Hydrogen

Optimistic scenarios project 90+ per cent impact reductions by 2050, with UK as exporter. Challenges persist—grid queues, mineral supply—but innovations like SOEL efficiency gains beckon. Sheffield's research equips policymakers; for professionals, it's a call to action in the clean energy race. Discover roles at higher-ed-jobs, rate professors via Rate My Professor, and access higher ed career advice. Stay informed on UK academia through AcademicJobs UK.

Read the University of Sheffield's press release for more.