This technical report presents a comprehensive framework for assessing and quantifying the flexibility potential of four key flexibility sources in modern power systems: utility battery storage, electrolysers, electric vehicles, and pumped hydroplants. With a focus on the European Union context, the report examines the technical characteristics, constraints, and flexibility potential of each source for providing critical power system services including frequency regulation, voltage support, and grid congestion management.
The assessment framework developed in this report enables systematic evaluation of flexibility sources across multiple dimensions, considering technical, economic, and operational factors. Through detailed analysis and case studies, the report demonstrates how different flexibility sources can be compared and optimized for specific grid applications, highlighting their complementary roles in supporting power systems with high shares of renewable energy.
The findings reveal that no single technology excels across all applications, with each source offering distinct advantages for specific services and contexts. Utility battery storage excels in fast-response applications, electrolysers offer valuable downward regulation capability, electric vehicles provide distributed flexibility resources, and pumped hydroplants deliver unmatched long-duration services. The report concludes that the EU’s growing flexibility needs will be best met through a diverse portfolio of these complementary resources, strategically deployed and operated to leverage their respective strengths.