Příspěvek v oblasti výzkumu navyšování potenciálu hydroelektrické akumulace

Abstract

The dissertation focuses on expanding the application potential of hydropower-based energy storage through novel pumped-storage concepts based on modular arrangements and the use of floating storage reservoirs. The work links system design and the development of conceptual variants with experimental verification of the principle, the design of measurement and control architecture, and, simultaneously, the development of a suitable turbine solution, particularly a Cross-Flow turbine. A key outcome of the work is the implementation of a laboratory-scale functional model of a modular pumped-storage hydropower plant with a single floating reservoir, serving as an experimental platform for verification of the operating principle and of the basic requirements for instrumentation and control. Within the testing campaign, 27 charging cycles were carried out, achieving an average volume utilization of 99.43%, an average cycle time of 499 s, and an average maximum tilt of 1.88°, thereby demonstrating the feasibility of the concept at laboratory scale while also enabling the identification of the system’s practical limitations. Building on the laboratory verification, a pilot-scale outdoor demonstrator of a modular pumped-storage hydropower plant with two floating reservoirs was developed. Its purpose is to enable longer-term testing under real operating conditions and to verify the robustness of the control system, including under non-standard and emergency states. The dissertation documents its fabrication and assembly in 2025 and its readiness for subsequent testing campaigns following completion of the turbine-generator unit. In parallel, the dissertation further develops the field of hydraulic machinery. It describes the construction of a test infrastructure and the experimental characterization of an impulse pico Cross-Flow turbine (28 W), for which an efficiency of approximately 55.7% at the design head and flow rate was demonstrated at 511 rpm on the basis of 77 measurements, including a critical discussion of measurement uncertainties. Furthermore, the dissertation presents a design methodology and CFD verification of a reaction Cross-Flow turbine which, at a head of 5.08 m and 220 rpm, achieved an efficiency of 79.43% and an output of 4.69 kW. Regression-based data processing indicates the potential for a broader operating range and supports considerations of standardized sizes for serial production. On a broader scale, the dissertation discusses the possibilities for the deployment of selected MPVE variants within power system conditions and based on simulations, presents an example of a potential application of a facility with an output of 1000 MW and a storage capacity of 6 GWh.