Performance analysis and optimization of a 20 MWh piston hydraulic gravity energy storage (PHGES) system

Denghui He, Yangfei Shen and Nan Luo

Energy, 2025, vol. 323, issue C

Abstract: The volatility and intermittency of renewable energy sources, such as wind and solar power, significantly affect energy supply stability. Consequently, the analysis and design of large-capacity energy storage systems have emerged as a crucial research area. This paper conducted a parameter analysis and optimization design of a large-capacity piston hydraulic gravity energy storage (PHGES) system employing MATLAB/Simulink numerical simulation. Initially, following the modular modeling concept, three subsystem modules were developed, encompassing the gravity well mathematical model, piston movement mathematical model and valve operation mathematical model. The reliability and validity of the simulation models were validated through experimental results. Furthermore, the investigation delved into the system dynamic characteristics, energy conversion performance, and economic viability under design conditions. Subsequently, employing parameter sensitivity analysis and correlation analysis methods, the study elucidated the influence trends and degrees of six key system design parameters—gravity well height, gravity well diameter, piston height, piston density, return pipe cross-sectional area, and valve opening area—on energy conversion performance and economic feasibility within the studied parameter ranges. Lastly, based on the parameter study outcomes, the primary impacting factors of the system were identified. Through the utilization of linear weighting and differential evolution algorithm, the optimal design parameters for a 20 MWh PHGES system were determined. The optimized system efficiency reached 76.67 %, reflecting a 0.27 % improvement over the initial design conditions. Economically, the levelized cost of energy (LCOE) decreased from 0.6921 CNY/kWh to 0.6258 CNY/kWh, signifying a 9.6 % reduction compared to the original system. The study provides a theoretical foundation and technical guidance for the utilization of large-capacity PHGES technology.

Keywords: Gravity energy storage; Piston hydraulic system; Optimization design; Differential evolution algorithm; Levelized cost of energy (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225014100
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:323:y:2025:i:c:s0360544225014100

DOI: 10.1016/j.energy.2025.135768

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().