Long-term integrated assessment of the water, GHG, and cost impacts of a transition to low-carbon hydrogen production: A case study for Canada

Hydrogen-based greenhouse gas (GHG) mitigation strategies can have multi-sector benefits and are considered necessary to reach net-zero emissions by 2050. Assessments of hydrogen scale-up have not included long-term implications for water resources. This work aims to fill this knowledge gap through a long-term integrated assessment of the water consumption, GHG emissions, and costs of conventional and low-carbon hydrogen scenarios to the year 2050. A framework was developed and 120 long-term scenarios were assessed for the largescale deployment of low-carbon hydrogen in a hydrogen-intensive economy. This study considered 15 different natural gas- and electrolysis-based hydrogen production technologies. A case study for Alberta, a western Canadian province and a fossil fuel-intensive region, was carried out. The results obtained project a cumulative mitigation of 9-162 million tonnes of carbon emissions between 2026 and 2050 through the implementation of low-carbon hydrogen production scenarios compared to the business-as-usual scenario. However, cumulative water consumption increases considerably with the large-scale deployment of low-carbon hydrogen, reaching 8 to 3815 million cubic meters. The adoption of green hydrogen technologies increases water consumption significantly. Depending on the jurisdiction of analysis and its water bodies, this increase may or may not be a long-term issue. Low-carbon hydrogen scenarios start becoming cost-effective as the carbon price rises to $170/ tCO2e. The developed integrated framework can be used globally to assess long-term hydrogen implementation with appropriate adjustments in data.