Korea's defense industry has begun research and development to shift the power pack—the "heart" of self-propelled howitzers and tanks, consisting of an engine and transmission—from the current diesel-centered setup to a hybrid that combines an electric motor. A hybrid engine produces less noise and heat, reducing the chance of detection by the enemy, and, being an electronic system, is also advantageous for implementing manned-unmanned teaming. With the United States moving ahead by deploying prototype hybrid tanks to front-line units this year, Korea is expected to accelerate its efforts.
According to the industry on the 3rd, Hanwha Aerospace has been pushing since this year to develop a hybrid power pack for the K9 self-propelled howitzer. STX Engine, which succeeded in localizing the K9 self-propelled howitzer's diesel engine, is in charge of integrating an electric motor with the existing engine, and SNT Dynamics is developing a dedicated transmission. Hanwha Aerospace, the system integrator (final assembly company), will install it in the K9 self-propelled howitzer. The corporations to handle the batteries are reportedly not yet finalized.
The current K9 self-propelled howitzer generates 1,000 horsepower with a diesel engine alone. While the capacity of the additional electric motor has not been finalized, a unit under 250 kW is being discussed. In that case, maximum output could expand to 1,200–1,300 horsepower. An industry official said, "Starting with the K9 self-propelled howitzer, it can be expanded and applied to other weapon systems such as the Redback (armored vehicle)," adding, "The goal is to produce a prototype in 2029."
The biggest advantages of a hybrid system are low noise and low heat. With conventional diesel engines, once the engine is turned off, power supply is cut and communications or radar cannot be used. To draw power, the engine must be kept running, and the resulting engine noise and heat inevitably expose one's position to the enemy. An industry official said, "If it moves on battery power without starting the engine, silent standby becomes possible, and reduced heat greatly improves survivability," adding, "Fuel efficiency will also improve."
A hybrid system is also essential for implementing manned-unmanned teaming, the paradigm of future battlefields. An industry official said, "A diesel engine can also enable manned-unmanned teaming, but that is mechanical, requiring additional equipment rather than being electronic," adding, "By switching to a hybrid, a fully electronic manned-unmanned teaming system becomes possible." With an electric motor and high-capacity batteries, it can also reliably supply power to artificial intelligence (AI) systems and advanced communications equipment.
A hydrogen-based hybrid engine for tanks is also under development. Hyundai Rotem, together with the Korea Research Institute for defense Technology planning and advancement (KRIT), is carrying out the "electrification technology based on high-capacity Hydrogen Fuel Cell" project. By combining a diesel engine, a Hydrogen Fuel Cell, and an electric motor, the goal is to unveil by 2035 a hydrogen hybrid powertrain prototype for the K2 tank that produces up to 1,500 horsepower. Based on this, Hyundai Rotem's plan is to build by 2040 a tank that runs solely on a Hydrogen Fuel Cell, removing even the diesel engine.
As hybrid engines emerge as essential components on future battlefields, leading global defense powers are a step ahead of Korea. In April last year, U.S. Army Chief of Staff Randy George said, "We plan to shorten the originally expected schedule (deployment in 2030) to one-third, delivering a new tank to soldiers within 24 to 30 months." The new tank is the "M-1E3," a hybrid system combining a diesel engine and an electric motor. It improves fuel efficiency by 50% and comes equipped with AI applications, pairing with robotic vehicles, and heat and electronic signature reduction devices.
The U.S. Army plans to deploy four prototypes of the new tank to some units within this year. An industry official said, "The hybrid system is a key means to change the paradigm of future ground warfare," adding, "It is like laying the groundwork for next-generation combat platforms that maneuver covertly, evading the enemy's eyes and ears, so development will speed up in the military as well as in the private sector."