Performance evaluation of a variable-speed contra-rotating pump-turbine for low-head pumped hydro energy storage: An experimental study
Journal article, 2025
Pumped Hydro Energy Storage (PHS) provides over 90% of the global long-duration energy storage capacity, yet many regions lack the steep terrain required for conventional high-head PHS. Low-head pumped hydro energy storage (LH PHS) systems address this gap in flat topographic regions but requires efficient pump-turbine technology for operation at variable low heads. This study investigates the use of a variable-speed contra-rotating pump-turbine (CR RPT) for LH PHS applications, presenting experimental results from a model-scale test rig stablished at Technische Universität Braunschweig. This test rig uses two open water surface tanks to provide head, unlike conventional hydraulic test rigs that use pumps. The CR RPT achieved hydraulic efficiencies over 80% for a wide range of operating conditions, peaking at 86.1% and 88.4% for pump and turbine modes, respectively. Additionally, dimensionless analysis revealed that the CR-RPT occupies a unique place in the market and that it achieves the largest power density among comparable hydraulic machines, facilitating greater power output and thus streamlining mechanical and civil engineering requirements for LH PHS.
Pump-turbine
Laboratory tests
Pumped hydro storage
Hydraulic machine characterization
Contra-rotating
Energy storage
Author
Ruben Ansorena Ruiz
Technische Universität Braunschweig
David Schürenkamp
Technische Universität Braunschweig
D. P.K. Truijen
Ghent university
FlandersMake@UGent – Corelab MIRO
J. P. Hoffstaedt
Delft University of Technology
Antonio Jarquin Laguna
Delft University of Technology
Jonathan Fahlbeck
Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics
Håkan Nilsson
Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics
Melvin Joseph
Advanced Design Technology Ltd
Mehrdad Zangeneh
Advanced Design Technology Ltd
J. D.M. De Kooning
FlandersMake@UGent – Corelab MIRO
Ghent university
Jonas Oldeweme
Technische Universität Braunschweig
Heiko Schwarz
Technische Universität Braunschweig
Nils Goseberg
University of Hanover
Technische Universität Braunschweig
Energy Conversion and Management: X
25901745 (eISSN)
Vol. 26 101009Augmenting grid stability through Low-head Pumped Hydro Energy Utilization & Storage (ALPHEUS)
European Commission (EC) (EC/H2020/883553), 2020-04-01 -- 2024-03-31.
Subject Categories (SSIF 2025)
Energy Engineering
Energy Systems
DOI
10.1016/j.ecmx.2025.101009
Related datasets
Experimental data for a low-head contra-rotating reversible pump-turbine [dataset]
URI: https://leopard.tu-braunschweig.de/receive/dbbs_mods_00078309