Author(s): Matthijs Den Dekker; Elena Vagnoni
Linked Author(s):
Keywords: No Keywords
Abstract: The transition toward climate neutrality is accelerating the adoption of Variable Renewable Energies (VRE) such as wind and solar. While these sources reduce greenhouse gas emissions, their variability increases the need for flexibility in the power grid. Hydropower Plants (HPPs), particularly pumped storage facilities, are the primary providers of clean and reliable grid flexibility. However, more flexible operation introduces frequent start-stop cycles that significantly affect component fatigue and reduce machine lifetime. This study quantifies the impact of such operational patterns on five HPPs, representing Francis, Pelton, and multistage pump types. By mapping operational data onto experimentally derived fatigue damage maps, the results show that start-stop cycles increase damage by approximately 10–16× for Francis Pump-Turbines (PTs), 2× for Pelton turbines, and up to 1,000× for multistage pumps. These findings emphasize the need for optimized maintenance strategies and further research on mitigating transient operation damage in flexible hydropower systems.
Year: 2026