Economic and Sustainable Energy Transition Enabled by Pumped-Storage Hydropower Plants

Energy storage is a key requirement for the global transformation towards a renewable and low carbon emitting energy system. Multiple technologies are competing, and the way forward is argued at many different levels and between different technical approaches with different advantages and disadvantages. However, pumped-storage hydropower has been a successful solution that has been utilized and improved for more than 110 years. The authors claim that pumped-storage hydro is the key to enable a rapid and sustainable global energy transformation.
This article compares storage technologies and present a case-study for how to achieve a 100% renewable electricity production in Germany including the surrounding electricity trading region. The article demonstrates how a full renewable production can be enabled by pumped-storage integration and compare with a power to gas approach. A discussion is included of the arising storage demand if Germany and surrounding countries with topographic favourable situations are to become fully served by pumped-storage hydropower to enable a 100% renewable electrical energy system. The specific role of Norway is discussed on its technical and geographic boundary conditions to support the European energy transition. The paper highlights the challenges and benefits from an integrated renewable energy system by applying conventional pumped-storage hydropower as well as enhanced underground pumped-storage hydropower. Finally, a discussion is also provided on the benefits of combining pumped-storage technology with deep underground caverns as lower reservoirs in order to cope with topographic and other boundary conditions such as urban areas and environmental aspects.