ZF's Propane Heat Pump Boosts Winter EV Range by 30%

July 2025 - German automotive supplier ZF has unveiled a groundbreaking new EV powertrain that features a propane-based heat pump capable of improving electric vehicle (EV) range by up to 30% during cold weather. This innovation, revealed in Top Gear's recent coverage, focuses on maximizing thermal efficiency and reducing reliance on battery power for cabin heating.

Why Cold Weather Is a Problem for EVs

Unlike internal combustion engine vehicles, which produce ample waste heat for warming the cabin, EVs must actively generate heat using energy from the battery — usually via resistive heaters. These systems are notoriously inefficient, consuming significant amounts of electricity and reducing driving range.

How ZF's Propane Heat Pump Works

ZF's new thermal management system uses a closed-loop vapor-compression cycle driven by R-290 (propane) as the refrigerant. About 200 grams of propane circulate through the sealed system, absorbing waste heat from the motor and electronics or pulling ambient heat from the outside air — even in subzero temperatures. This heat is then used to warm the vehicle’s cabin and battery.

• Closed-cycle: The system is sealed; propane continuously circulates in a liquid/vapor cycle with no combustion.
• No emissions: Since no fuel is burned, the system produces zero carbon emissions.
• Low climate impact: Propane has a GWP100 (Global Warming Potential over 100 years) of ~0.02, far lower than traditional HFC refrigerants.
• High efficiency: The heat pump uses significantly less energy than resistive heaters, preserving range.

Benefits for EV Owners

This heat pump setup enables smarter energy use, particularly in winter conditions:

• Reduces the need for battery-draining electric resistance heating
• Boosts EV range in cold climates by up to 30%
• Maintains passenger comfort and battery thermal management more sustainably

Safety and Sustainability

Though propane is classified as a mildly flammable refrigerant (A3), the system is engineered with automotive-grade safety measures to ensure reliability. Propane-based heat pumps are already widely used in European residential and RV heating systems. Their adoption in EVs could signal a broader industry shift away from synthetic refrigerants with high environmental impact.

A Glimpse into the Future of EV Efficiency

ZF's innovation is part of a wider effort to improve real-world EV performance under diverse climate conditions. As range anxiety and cold-weather inefficiencies remain top concerns for potential EV buyers, technologies like this could play a pivotal role in mainstream adoption.

By turning waste heat into usable thermal energy and leveraging an eco-friendly refrigerant, ZF's propane heat pump offers a glimpse of a more efficient, cleaner, and smarter EV future.