Mahle has unveiled a new heat recovery system designed to improve cabin heating efficiency in electric vehicles, saying the technology can reduce energy demand for climate control by about 20% compared with conventional exhaust air systems.
Heating remains one of the main factors affecting driving range in battery-electric vehicles during winter. Unlike combustion-engine cars, which use engine waste heat to warm the cabin, EVs must rely largely on electric heating elements powered by the traction battery due to the high efficiency of their drivetrains.
Mahle’s HeatX Range+ system seeks to address this limitation by recovering thermal energy from cabin exhaust air. The system integrates with the vehicle’s air conditioning unit and uses the evaporator to capture residual heat before the air exits the vehicle.
“As the air directed outside passes through the evaporator, it heats the refrigerant while leaving the cabin. The refrigerant then transfers the stored energy to the fresh air intake before it enters the vehicle interior,” Mahle said in a statement. “This efficiently preheats the fresh air and reduces heating power demand at winter temperatures compared to conventional exhaust air systems.”
According to the company, tests conducted on a mid-size battery-electric vehicle at an outside temperature of minus 7 degrees Celsius and a cabin temperature set to 20 degrees Celsius showed a reduction in heating system energy consumption of around 20%. Alternatively, the efficiency gain could extend driving range by approximately 10 kilometres per battery charge under those conditions.
Mahle said the system is designed to maintain airflow performance and acoustic characteristics of existing air conditioning systems and can be integrated into current vehicle architectures without major redesigns. The configuration is optimised for the refrigerant R1234yf and can be adapted to alternative refrigerants with limited modifications.
“Our HeatX Range+ heat recovery concept maximizes the everyday practicality of electric vehicles in winter and makes a decisive contribution to further increasing the attractiveness of electric mobility,” said Martin Wellhöffer, member of the Mahle Group Executive Board responsible for the Thermal and Fluid Systems business unit.
Uli Christian Blessing, head of development for Thermal and Fluid Systems, added that the company has longstanding experience in this area. “As early as the 1990s, MAHLE introduced the ‘Economizer’, the first cabin heat recovery system concept for passenger and commercial vehicles, thereby pioneering today’s trend toward efficient cabin climate control,” he said.