Two-step Approach Simulating the Unit Commitment of Highly Complex Hydraulic Systems in the Future European Power System

The increase in supply-dependent renewable energy sources and the decommissioning of thermal power plants lead to an increasing need for flexibility in the future European electricity supply system. In this context, hydroelectric power plants represent a mature and renewable flexibility option. The EU Horizon 2020 project "HydroFlex" aims to increase the value of hydropower through increased flexibility. To this end, the project aims to develop a flexible turbine capable of very flexible operation and in particular several start/stop cycles per day. In order to both estimate the operational requirements for hydraulic turbines in the future and to systemically evaluate the flexible turbine developed in the project, a unit commitment model based on a European electricity market simulation is required. Due to the high complexity resulting from the large number of hydraulic interconnections in the Nordics, permissible simplifications are needed to solve the problem in a reasonable computing time. The paper presents a method to simulate the unit commitment of highly complex hydroelectric power plant parks in the future European power system, which is necessary to evaluate the technological advantages of the turbine developed in the "HydroFlex"-project.