At Busworld Europe 2025, Eberspaecher will become the first manufacturer to showcase bus air-conditioning systems using propane (R290) as a natural refrigerant. The company is presenting its roof-mounted AC135 and AC138 EVO models, offered both as standard equipment and as retrofit solutions for diesel vehicles.
Driven by the EU F-Gas Regulation and global efforts to phase out harmful refrigerants, propane offers a sustainable alternative with a global warming potential of just ~3. Covering a wide temperature range from –15°C to +55°C, it is particularly suited to warm climates and heat pump applications. For cooler regions, Eberspaecher also provides CO₂ (R744)-based systems.
The AC135 and AC138 EVO systems use a direct setup, eliminating additional heat exchangers. This reduces components, weight, and energy losses, while improving overall efficiency. Safety measures derived from railway technology ensure propane use remains secure in all bus applications.
A key highlight is the retrofit solution for diesel buses. Partnering with an external specialist, Eberspaecher has developed a generator-driven system to power electric compressors, enabling diesel vehicles to adopt natural refrigerant technology for the first time.
All models are equipped with the E-Control module, which integrates all thermal management functions. Through the cloud-based e-connected platform, operators gain access to over-the-air updates, real-time fleet monitoring, and predictive maintenance capabilities.