Berlin city buses go beyond HFCs
[ added 7 July, 2010 ]
[ return to list ]
Rate
In 2007, the president of the German car maker association VDA, declared that the German car makers would be the first ones to use the natural refrigerant CO2 in car air-conditioners. In 2010, the VDA backed down from past promises and opted for yet another generation of chemical refrigerant. However, the local public transport provider in the city of Berlin has just announced the introduction of CO2 air conditioning technology in seven of its city buses, with more expected to come.
Berlin’s local transport provider Berliner Verkehrsbetriebe (BVG) presented the concept of CO2 (R744) air conditioners in city buses during a press conference on 2 July 2010. Seven buses fitted with R744 air conditioners will be subject to a tough real-life testing during a hot Berlin summer and drive on average 400 km per bus every day. After a initial test with an R744 system supplied by CO2 mobile air conditioning (MAC) expert Konvekta in one city bus had brought highly positive results, BVG decided to invest in a broader-scale test by equipping six more buses with the technology. BVG expects to publish first results regarding cooling capacity, reliability and durability of CO2 MAC by this autumn, and hence actively contribute to its optimisation and rapid serial use. Once the tests are completed, BVG will consider installing R744 air conditioning in all city buses.
100 tonnes of leaked HFC refrigerant from German buses in 2008
The use of environmentally friendly refrigerant is urgently needed given that bus air conditioners contribute a very high share in overall carbon emissions. While in 1993 only 5% of all new city buses in Germany were equipped with an air conditioning system, this figure rose to 64% in 2008. Moreover, 100% of all long-distance coaches today are equipped with A/C. At an average leakage rate of 13.3% for new coaches and 13.7% for new city buses, all German buses together emitted 100 tonnes of climate warming refrigerant R134a in 2008 alone.
R744 in bus air conditioning praised by the German Federal Environment Agency
The President German Federal Environment Agency Umwelt Bundesamt (UBA) Flasbarth praised the BVG decision to replace the chemical refrigerant R134a in bus air conditioners with the 1.430 times less climate damaging CO2 in its cooling system. He also urged other public transport providers to follow Berlin’s move and adopt CO2 as a standard in mobile air conditioning as early as possible.
German authorities have repeatedly warned against continuing the use of chemical refrigerants in mobile air conditioning systems, since natural refrigerant solutions to replace them are available.
Chemical refrigerants an “unsafe temporary solution”
Tests on new generation synthetic refrigerant HFC1234yf for mobile air conditioning conducted by the German Federal Institute for Materials Research and Testing (BAM) have revealed serious risks for the life of drivers and rescue personnel in case of fire.
Previously, the German Environment Minister Sigmar Gabriel had described car manufacturers that would opt for 1234yf as embarking on a “high economic and technical adventure”. More recently, in May 2010, when the German carmakers silently decided to back down from past promises and opt for yet another chemical option that 1234yf represents, the UBA Vice-President Thomas Holzmann desribed their turnaround as “extremely regrettable”. The decision was “all about economic interests of the chemical industry and about rigid structures in the supply chain”.
To read the press release by BVG and UBA (in German) click here.
