Regionalisation in high share renewable energy system modelling

Governments are setting ambitious targets to tackle the issue of global warming by switching to renewable energy sources and reducing CO2 -emissions. For example, as announced in November 2020, Canada aims to achieve net zero GHG emissions by 2050. Large countries such as Canada cannot easily apply a global energy strategy, each region having different energy demands and potentials. Optimization-based energy models can be used to simulate and compare different energy transition pathways - one of them is based on the use and production of hydrogen. For this purpose, other methods of defining regions within energy system models are considered by considering (i) political boundaries and (ii) clustering geographical and demographic characteristics. We propose a new modeling strategy by comparing two region definition strategies applied to the case of Canada, assessing the competing role of electricity and Hydrogen as energy vectors. Our case study shows the electrification of the energy system is essential to achieve net-zero emissions across all sectors to satisfy the mobility, heating, and electrical demands. In contrast, the role of hydrogen in the power, industrial, and transport sectors for valorizing excess electricity and decarbonizing them is identified.