Scalable, modular technology can be optimized for various applications, including consumer vehicles, commercial vehicles, industrial equipment, back-up generators and energy storage, and decentralized fueling stations. It is a compact, high-power density hydrogen engine which provides power delivery by converting hydrogen into electricity – as a direct replacement for applications using diesel fuel. The modular units can stack together for increased power. Add-on tanks increase energy storage. Output starts at 125 kW with a usable life that exceeds the DOE 1,000,000-mile target by achieving over 90,000 cycles.