An emission-free bus air-conditioning solution for tomorrow’s electric city bus transport – Eberspaecher will be presenting the new AC 136 HP CO2 roof-mounted air-conditioning system at Busworld Europe in Hall 5, Stand 535. The electric thermal management system is specially designed for the environmentally friendly and safe refrigerant R744 (carbon dioxide) and ensures an optimum climate comfort in the passenger compartment in temperate climates at all times of the year.
In recent years, Eberspaecher has conducted extensive research into the efficient use of the natural refrigerant R744 in bus air-conditioning systems. The climate specialists are now using this know-how to further develop the proven AC 136 AE HP into a CO2 heat pump: “With the AC 136 HP CO2, we will be offering emission-free and environmentally friendly thermal management for clean electric city bus transport in Europe from 2021,” emphasizes Oliver Wels, General Manager of Eberspaecher Climate Control Systems Bus & Coach.
Powerful heating and cooling thanks to heat pump technology
Based on the concept of the proven predecessor version, the AC 136 HP CO2 is specifically tailored to the requirements of hybrid and electric buses: Thanks to its reversible refrigeration circuit, the heat pump technology enables various cooling and heating outputs of up to 22 kilowatts in one system, which ensures the passenger compartment is at the right temperature at all times of the year.
Extended range of electric buses in temperate climates
Electric heat pumps draw its heat with a high COP value (Coefficent of Performance) from the ambient air. In this way, it not only heats the out blown air much more efficient than additional electrical air or water heaters, but also reduce the load on the bus battery. In addition, CO2 allows the heat pumps to operate in lower temperature ranges than chemically produced refrigerants. This way, the AC 136 HP CO2 requires no additional electric heating load from the bus when used at temperatures as low as minus 15 degrees Celsius: The complete thermal management system thus extends the range of electric buses in temperate climates and offers great advantages for fleet operators of electric city buses.
Environmentally friendly thermal management with R744 refrigerant
As opposed to the chemical agents R134a and R1234yf, the natural refrigerant R744 is much more environmentally friendly and safe: With a GWP (Global Warming Potential) value of 1, CO2 has the lowest global warming potential used in bus thermal management. In addition, CO2 is not flammable or toxic compared to other natural refrigerants such as ammonia or hydrocarbons. By using carbon dioxide, Eberspaecher is making a significant contribution to environmentally friendly local public transport in European cities.
