Towards Highly Renewable Power Systems: Algorithms, Optimization Models & Techno-Economic Analyses

We are moving towards highly renewable power systems, which presents technical as well as economic challenges. Instead of conventional thermal power plants, which can be built in close proximity to demand centers, locations with high renewable potential may not necessarily be situated nearby demand centers. Hence, highly renewable power systems require adequate and reliable grid infrastructure to transport the electric energy from where it is generated to where it is needed. Moreover, renewable generation expansion needs to take the grid restrictions into account, as it can take much longer to build new power lines compared to adding renewable capacities. Investments in the transmission and distribution grids are also required, adding to the costs of expanding renewable capacities.
Power system models can help identify and overcome the technical challenges of integrating more renewables and analyze the subsequent economic impacts. This thesis contributes by improving power system modeling in three key aspects: (1) It introduces a novel way to use open-source grid data optimized especially for power system models. This opens the possibility of building models that include power flow calculations for regions where it was not possible before due to the lack of available data. For example, a power system model of the African continent is built and a transition towards 100% renewables is analyzed. (2) Wind power is essential for reaching highly renewable power systems. Current data for wind power potentials are often hard to use for generation expansion planning purposes in power system models; as for example, the potentials are not available per power grid node. As part of this thesis, a GIS-based approach for calculating wind power potentials per grid node is presented. The available wind power potentials per grid node can easily be used for generation expansion planning in power system models. (3) Electricity is an important good and affordability must be ensured despite all the necessary investments for transitioning to renewable energies. The effects of Austria’s electricity transformation and its impact on electricity prices and demand are analyzed by coupling a technical model of the power system with a macroeconomic model.
The newly developed algorithms and advancements in power system optimization models and techno-economic analyses, which constitute original contributions of this thesis, provide better insights into the effects of moving towards highly renewable power systems.