A transport refrigeration unit (TRU) system is provided and includes a high-voltage power source, a low-voltage power source, at least one of the high-voltage power source and the low-voltage power source including a fuel cell configured to provide electricity to the transport refrigeration unit, a first electrical load, which is optimally powered by the high-voltage power source, a second electrical load, which is optimally powered by the low-voltage power source and an electrical distribution system by which the high-voltage power source is directly electrically connected to the first electrical load and the low-voltage power source is directly electrically connected to the second electrical load.