Objective Existing gravity energy storage technologies are constrained by the mechanical characteristics of centralized drives and flexible cable traction, commonly suffering from bottlenecks such as low power density, discontinuous operation, and performance degradation with increasing lift height. Therefore, this paper proposes a large-scale long-duration gravity energy storage system based on "solid flow", aiming to break through traditional mechanical constraints and meet the demands of new power systems for high-capacity and highly terrain-adaptive energy storage.

Method Based on the design philosophy of transforming discrete masses into quasi-continuous flowing media, the power limitation mechanisms of discrete hoisting and flexible traction systems were analyzed. A distributed power architecture and a push-type power transmission mechanism were proposed, utilizing multi-stage power units for relay drives along the path. Two system topologies, chain drive and gear-rack rigid transmission, were constructed. Through the establishment of steady-state power models and efficiency models, the mechanical responses, power characteristics, and heavy-load adaptability of different topologies under continuous operation were compared and analyzed.

Result The results show that the system achieves physical decoupling between load transfer/output power and lifting height, overcoming the defect of linear decay of effective payload rate with height in traditional technologies. The single-channel average power of the gear-rack configuration can reach 480 MW at a height difference of 600 m, showing a significant improvement compared to the chain drive. The energy storage capacity and power level of the system increase by one to two orders of magnitude compared to existing technologies. The power density of its lifting and descending channels exhibits a constant characteristic insensitive to height.

Conclusion The solid flow technology effectively solves the problems of discontinuous operation and height limitations of gravity energy storage through the rigid continuous transmission mechanism. It validates the engineering feasibility for high-drop and long-duration energy storage applications, providing a highly terrain-adaptive technical solution for constructing large-scale physical energy storage systems using natural mountain terrains.