Swiss train manufacturer Stadler will equip 132 new trains and 34 intermediate modules for the Cologne Transport Agency (KVB) with natural refrigerant-based HVAC systems in a contract worth around €700 million ($816 million).
Stadler has said the trains will include “state-of-the-art” technology, including high-efficiency air-conditioning with a natural refrigerant, but it has not confirmed any details about the thermal management system’s manufacturer, capacity or refrigerant.
The company has previously deployed propane (R290)-based HVAC units from Austria’s Liebherr-Transportation Systems on Nordic Express long-distance trains. Mitsubishi Electric has also discussed developing R290 HVAC systems for Stadler, with a focus on the German market.
“The criteria for the decision of the air-conditioning systems includes environmental aspects, availability and costs,” a Stadler representative told NaturalRefrigerants.com.
With a service life of over 30 years, the use of natural refrigerants will help ensure the new trains remain compliant with future environmental regulations and maintain low climate impact throughout their operation. Stadler’s long-term service partnership with KVB will cover maintenance to ensure safe, reliable and efficient operation.
The modular design allows trains to be extended up to 70 meters (230 feet), accommodating as many as 470 passengers, a substantial capacity boost compared to the city’s current rail vehicles that enables more efficient infrastructure use.
The first 10 trains and five connecting modules are scheduled for pre-series delivery in 2029, with full series production running from mid-2030 through the end of 2032.
Natural refrigerants in trains
Stadler has said that it currently leads the market with natural refrigerant HVAC systems installed in approximately 55 of its vehicles.
“We currently have several orders that use natural refrigerants, so the number of vehicles with such technology will increase in the future,” the company’s representative said. “Whenever possible and if required by the customer, we equip our trains with natural refrigerants. European customers mostly opt for natural refrigerants, as does KVB.”
“We currently have several orders that use natural refrigerants, so the number of vehicles with such technology will increase in the future.”
Stadler
A number of other rail manufacturers are also turning to natural refrigerant-based technologies. For instance, Mitsubishi Electric has said it will be supplying R290 HVAC units for Siemens Mobility trains in Munich’s suburban rail system. Konvekta has built a CO2 (R744) heat pump for a tram in Bonn from the Škoda Group – a Czech Republic-based manufacturer unaffiliated with the car company of the same name.
The German Environment Agency (UBA) recently identified R290 as a “feasible option” for train AC systems, offering real-world performance and safety levels comparable to today’s dominant HFC R134a while avoiding high GWP.
