Pressurised gas storage device

A pressurized gas storage device is preferably designed as a gas storage power plant and comprises two gas storage volumes that are connected to a gas transport network (7), wherein the gas storage volumes communicate with one another via at least one first manifold (3) and are connected to the gas transport network via at least one second manifold (6). The pressurized gas storage device further comprises at least one compressor (4) that is arranged between the second manifold (6) and the first manifold (3), as well as at least one expansion turbine (11) with generator (12) that is arranged between the second manifold (6) and the first manifold (3), wherein the compressor (4) and the expansion turbine (11) are connected in parallel between the second manifold (6) and the first manifold (3), and wherein the compressor (4) and the expansion turbine (11) are connected such that gas can be transferred between the gas storage volumes by utilizing a pressure differential during operation of the generator (12) or by creating a pressure differential during operation of the compressor (4).