Soft integration of an Integrated Assessment Model and an Energy System Model for the multi-sectorial evaluation of African energy transition pathways

Climate change poses significant challenges to global and regional energy systems, particularly in Africa, where rapid economic growth and increasing energy demands must be balanced with mitigation efforts. Although the entire African continent accounts for only 3.8% of global GHG emissions, its demand for modern energy is expected to increase by a third between 2020 and 2030. African nations have committed to climate action through the Paris Agreement, which sets ambitious goals to limit global temperature rise to below 1.5°C or well below 2°C by 2100. However, achieving these targets requires a comprehensive understanding of the interplay between energy, water, land use, and climate systems, as well as the identification of cost-effective pathways for the energy transition. While global Integrated Assessment Models (IAMs) are frequently employed to assess the impacts of mitigation scenarios on human and environmental dynamics, they tend to simplify spatial dimensions, which does not allow to fully capture the effects of national plans. This limitation is particularly evident in developing regions, such as Africa. Energy System Models (ESMs), on the other hand, offer finer spatial resolution, but lack the ability to represent global dynamics, often oversimplifying decision-making by focusing primarily on cost minimization. This study addresses the critical need for integrated modeling approaches to evaluate the effectiveness of climate change mitigation strategies in the Global South. The objective is the creation a soft-link between the Global Change Analysis Model (GCAM) and the energy systems model OSeMOSYS-TEMBA AHA to evuate the effects of the Paris Agreement climate pledges, both mid-term and long-term, on the African energy sector. The framework so-built enriches the multi-sector dynamics representation of an IAM with the detailed characterisation of energy generation and capacity expansion dynamics of an ESM. Moreover, thanks to the comprehensive representation of existing and future African hydropower projects included in OSeMOSYS-TEMBA AHA, this study specifically examines the role of hydropower in Africa's energy transition.