An electric rail carriage is described. The electric rail carriage may include a train carriage. The train carriage may be arranged to be powered by at least one power module, which is arranged to generate electric power. The carriage may include a main chassis, and at least one power module bay located underneath the main chassis. A power module can be removably located and secured within the power module bay, such that the power module is supported underneath the main chassis. A method of installing the power module into a power module bay is described.