The boosterpump concept for reconstruction of hydropower plants to pumped storage plants
Kaspar Vereide, Livia Pitorac, Rachel Zeringue, Arne Kollandsrud
Abstract
The need for electric energy storage in the ongoing energy transition with large-scale construction of renewable energy leads to increasing interest for upgrading existing hydropower plants to pumped storage plants. Such upgrading is possible by using existing dams and waterways, and only upgrade the electromechanical equipment. However, this alternative has several technical limitations that must be overcome. The boosterpump concept is a possible solution to overcome these technical limitations. This paper presents the concept and a demonstration on two case-study hydropower plants. A novel electro-mechanical layout and hydraulic design has been developed. The layout, operation, physical dimensions, performance, costs and market analyses are presented. The costs are compared to constructing a new reversible unit in parallel with reuse of the existing dams and waterways. The boosterpump concept is found technically feasible for both Roskrepp HPP and Vinje HPP, and the technology is currently considered to be at TRL 4-5. The cost calculations show that reconstructing with a boosterpump costs 25-35% less than installing a new reversible unit constructed in parallel. The reconstruction is only found economically feasible for the Roskrepp HPP under the given assumptions and market expectations for these two projects.