Modeling Spain's Energy System Transformation: The Role of Thermal Energy Storage Power Plants in Reducing CO2 Emissions

Abstract

In a world that is moving fast to low carbon energy systems, Spain is leading the transformation owing to its self-imposed renewable energy targets with abundant sun and wind resources. Although the increasing share of variable renewables helps reduce generation costs, it also leads to intermittent fluctuations and electricity supply-demand imbalances. To tackle these challenges, this thesis assesses the integration of thermal storage power plants (TSPPs) as a way to foster large-scale renewable deployment in Spain by means of techno-economic modeling, scenario analysis and application of the REMix framework. The thesis presents a systematic review of the Spanish power system transition from fossil-based to renewable-based generation; analyzes optimization strategies for storage integration using energy system modeling; and systematically compares alternative deployment strategies for TSPPs. Using detailed techno-economic data, the work describes scenarios for the years 2030, 2040, and 2050, quantifying system costs, storage utilization, technology mix and cross-border energy transfer. The results show that the optimum deployment of TSPPs leads to a significant reduction in the curtailment of renewables. Further, it reduces marginal costs in comparison to proportional allocation strategies. The study makes a contribution by offering strong technical evidence that the TSPP integration provides Spain with an achievable, economically acceptable, and environmentally desirable route to decarbonizing its energy system. By which Spain is not only pursuing it’s national roadmap, but also provides knowledge that can be deployed in other high-renewable systems across the world.