A modular fuel cell system comprising: - a plurality of fuel cell modules (110, 410), each fuel cell module (110, 410) comprising a fuel cell, an intake air interface (113, 413) for providing intake air to the fuel cell module (110, 410), and an exhaust gas interface (112, 412) for conducting away exhaust gas from the fuel cell module (110, 410); - an intake air manifold connected to each of the intake air interfaces of the fuel cell modules (110, 410), the intake air manifold containing a plurality of intake air modules (141, 142, 143), wherein each intake air module (141, 142, 143) is releasably connected to at least one adjacent intake air module (141, 142, 143) and connected to at least one of the intake air interfaces for providing intake air from the intake air manifold to the at least one of the intake air interfaces; - an exhaust gas manifold connected to each of the exhaust gas interfaces of the fuel cell modules (110, 410), the exhaust gas manifold containing a plurality of exhaust gas modules (131, 132, 133), wherein each exhaust gas module (131, 132, 133) is releasably connected to at least one adjacent exhaust gas module (131, 132, 133) and connected to at least one of the exhaust gas interfaces for receiving exhaust gas from at least one of the exhaust gas interfaces; - a turbocharging system comprising at least one turbocharger having a compressor and a turbine, wherein the turbine is in fluid connection with the exhaust gas manifold for receiving the exhaust gas from the exhaust gas manifold, and the compressor is in fluid connection with the intake air manifold for providing charged intake air to the intake air manifold. - a plurality of fuel cell modules (110, 410), each fuel cell module (110, 410) comprising a fuel cell, an intake air interface (113, 413) for providing intake air to the fuel cell module (110, 410), and an exhaust gas interface (112, 412) for conducting away exhaust gas from the fuel cell module (110, 410); - an intake air manifold connected to each of the intake air interfaces of the fuel cell modules (110, 410), the intake air manifold containing a plurality of intake air modules (141, 142, 143), wherein each intake air module (141, 142, 143) is releasably connected to at least one adjacent intake air module (141, 142, 143) and connected to at least one of the intake air interfaces for providing intake air from the intake air manifold to the at least one of the intake air interfaces; - an exhaust gas manifold connected to each of the exhaust gas interfaces of the fuel cell modules (110, 410), the exhaust gas manifold containing a plurality of exhaust gas modules (131, 132, 133), wherein each exhaust gas module (131, 132, 133) is releasably connected to at least one adjacent exhaust gas module (131, 132, 133) and connected to at least one of the exhaust gas interfaces for receiving exhaust gas from at least one of the exhaust gas interfaces; - a turbocharging system comprising at least one turbocharger having a compressor and a turbine, wherein the turbine is in fluid connection with the exhaust gas manifold for receiving the exhaust gas from the exhaust gas manifold, and the compressor is in fluid connection with the intake air manifold for providing charged intake air to the intake air manifold.