Abstract: A retrofit mining haul truck includes a hybrid hydrogen fuel cell/battery-based powerplant in place of a carbon fuel-based powerplant. The retrofit mining haul truck includes a frame, a tray coupled to the frame, and a deck coupled to the frame forward of at least a portion of the tray. A battery system is mounted to the deck of the retrofit mining haul truck. A hydrogen storage system (HSS) is installed in an engine bay volume of the retrofit mining haul truck. The engine bay was configured to contain a combustion engine (e.g., a diesel engine) prior to retrofitting the retrofit mining haul truck. At least a portion of a fuel cell system is installed in a wheel pocket of the retrofit mining haul truck. The wheel pocket was configured to contain a diesel tank prior to retrofitting the retrofit mining haul truck.