The Komatsu HB205-1 is a 20-ton hybrid hydraulic excavator designed for enhanced fuel efficiency and reduced emissions. It features a 104 kW (139 hp) diesel engine combined with an electric swing motor and ultra-capacitor energy storage system. This setup allows for energy recovery during swing braking, leading to up to 41% fuel savings and a 10 kg/h reduction in CO₂ emissions compared to conventional diesel-only models .