The application relates to a tubular turbine device for a fluid transport network, including at least one running equipment arranged on a turbine shaft, at least one guiding equipment arranged upstream of the running equipment, and at least one generator coupled to the turbine shaft and configured to convert a mechanical energy into electrical energy, at least one cross-section adjustment equipment configured to change a cross-sectional area of the tubular turbine device that can be flowed through depending on the volume flow of the fluid flowing through the tubular turbine device.