The goal of EMPOWER (long title: Eco-operated, modular, highly efficient, and flexible multi-powertrain for long-haul heavy-duty vehicles) is to deliver two flexible, modular, and scalable zero-emission heavy-duty vehicles with a gross vehicle weight equal or above 40 tons. Both vehicles have an electric powertrain. While in one vehicle the electrical energy is generated by a fuel cell system, which enables a range of 750 km, in the other a battery alone provides a range of 400 km.