Enhanced gas turbine power output during under-frequency operation

Disclosed is a gas turbine power plant (1), comprising a compressor (2), a combustor (3), and a compressed-air line (6) interconnecting the compressor (2) and the combustor (3), wherein a pressure vessel (8) is connected to the compressed-air line (6) via a further compressed-air line (9). Further disclosed is a method for operating a gas turbine power plant (1).