Marwan Sendi
Senior Engineer
Life Cycle Assessment Group, Technology Strategy & Planning Department, Saudi Aramco. Department of Chemical Engineering, Imperial College London, United Kingdom
Marwan Sendi is a senior engineer in the Life Cycle Assessment Group at Saudi Aramco’s Technology Strategy and Planning Department, where he focuses on technology assessment and net-zero strategy. He holds a PhD from Imperial College London, where his research centered on geospatial modeling of chemical processes and energy systems, including direct air capture systems.
Participates in
TECHNICAL PROGRAMME | Energy Fuels and Molecules
Hydrogen (Green and Blue); Ammonia; Methanol
Forum 14 | Digital Poster Plaza 3
28
April
12:30
14:30
UTC+3
Low-carbon hydrogen—particularly electrolytic “green” hydrogen generated from renewable electricity—features in many national net-zero strategies because it promises lower carbon emissions in traditional uses and decarbonization across a wide range of sectors, including heat, power, and mobility. Yet the strict regulations frequently proposed to ensure hydrogen’s “green” credentials, such as hourly time-matching of electrolyzer power consumption to local renewable generation, can drive up costs significantly. This work investigates whether policies that demand perfect, hourly time-matching with renewable electricity are truly necessary or whether more relaxed strategies could enable affordable low-carbon hydrogen production.
We use a resource-task network modelling framework, which links hydrogen production—via water electrolysis—with regional renewable generation and energy storage at an hourly resolution. We use 20 years of weather data to capture inter- and intra-annual variability of renewable sources. Using this framework, the least-cost system design and operation can be determined based on differing time-matching constraints. By comparing scenarios that allow partial reliance on grid electricity against those requiring perfect hourly time-matching with renewables, we can quantify the trade-offs in production cost and environmental impact.
Our findings show that strict hourly time-matching requirements can substantially increase hydrogen production costs while providing only marginal emissions reductions, leading to CO2 avoidance costs higher than other expensive mitigation options such as direct air capture. This suggests that overly strict time-matching rules yield limited climate benefits relative to their cost, whereas a modest relaxation of these requirements offers a more pragmatic and cost-effective pathway to low-carbon hydrogen production—and thus potentially enabling a broader adoption.
Moreover, in jurisdictions with credible near- to medium-term decarbonization targets, fully grid-powered electrolysis may have a lifetime carbon intensity comparable to, or even lower than, that of other low-carbon hydrogen pathways. This underscores the importance of rapid, broader grid decarbonization as a key policy priority.
Co-author/s:
Matthias Mersch, Research Associate, Clean Energy Processes (CEP) Laboratory, Department of Chemical Engineering, Imperial College London.
Niall Mac Dowell, Professor, Centre for Environmental Policy, Imperial College London.
We use a resource-task network modelling framework, which links hydrogen production—via water electrolysis—with regional renewable generation and energy storage at an hourly resolution. We use 20 years of weather data to capture inter- and intra-annual variability of renewable sources. Using this framework, the least-cost system design and operation can be determined based on differing time-matching constraints. By comparing scenarios that allow partial reliance on grid electricity against those requiring perfect hourly time-matching with renewables, we can quantify the trade-offs in production cost and environmental impact.
Our findings show that strict hourly time-matching requirements can substantially increase hydrogen production costs while providing only marginal emissions reductions, leading to CO2 avoidance costs higher than other expensive mitigation options such as direct air capture. This suggests that overly strict time-matching rules yield limited climate benefits relative to their cost, whereas a modest relaxation of these requirements offers a more pragmatic and cost-effective pathway to low-carbon hydrogen production—and thus potentially enabling a broader adoption.
Moreover, in jurisdictions with credible near- to medium-term decarbonization targets, fully grid-powered electrolysis may have a lifetime carbon intensity comparable to, or even lower than, that of other low-carbon hydrogen pathways. This underscores the importance of rapid, broader grid decarbonization as a key policy priority.
Co-author/s:
Matthias Mersch, Research Associate, Clean Energy Processes (CEP) Laboratory, Department of Chemical Engineering, Imperial College London.
Niall Mac Dowell, Professor, Centre for Environmental Policy, Imperial College London.
