This IAM COMPACT Deliverable, D4.9, presents three studies related to the European sub-national and sectoral deep dives into questions of climate change mitigation, air pollution co-benefits and regional inequalities, energy security and resilience, and policy assessment.

The first study quantifies air quality and health impacts of 250 mitigation scenarios in the European electricity sector in 2035 across 296 NUTS-2 sub-national regions. It shows that the direct PM2.5 concentrations attributable to electricity generation could be reduced by 45% to 99%, if Europe follows a net zero emissions goal as compared to a reference system. The most vulnerable regions (Balkans, North-West Germany, Southeast France, and the West Midlands in England) would benefit from higher air quality co-benefits than the continental average.

The second study, conducted as part of the first IAM COMPACT Policy Response Mechanism (PRM), uses a multi-model approach for Greece and the European Union and shows that the energy transition necessitates diversification from energy security and flexibility perspectives, combining dispatchable and variable generation, flexible demands, and energy storage.

The third study, also part of the 1st PRM cycle of the project, uses a multi-model approach for the Greek power and residential sectors and shows the need to accelerate investments in variable renewable generation and energy storage and to phase out natural gas between 2037 and 2044. The required renovation rate in Greece should reach 2.5% to 3.5% of the housing stock per year with the focus on electrification rather than natural gas as a transition fuel.