Recently, the 'Dongchu No.1'—China's inaugural, domestically developed kilowatt-scale underwater pumped storage energy system, engineered by the Dongfang Research Institute under the auspices of Dongfang Electric Corporation—completed a rigorous 10-day comprehensive underwater trial in Minhu Lake, Fujian Province, marking a resounding success. This achievement represents a significant leap forward, bridging the gap in China's innovative underwater pumped storage energy technology landscape. The trial underscored the viability of underwater energy storage solutions, showcasing their remarkable environmental adaptability and suitability for deployment in conventional reservoirs across a range of depths. This breakthrough effectively mitigates the constraints associated with site selection for onshore pumped storage power stations, paving the way for a novel technological approach to constructing regional flexible regulation systems.