BERLIN (dpa) – An increasing number of cars in Germany are powered by compressed natural gas (CNG) and according to the Environment Ministry in Berlin, there are now 25,000 methane-driven cars on the country’s roads.
Yet recent reports of defective valves and gas leaks dogging the best-selling model, the Italian-made Fiat Multipla Bi-Power, has also brought the debate about safety to the fore.Karl Wolfgang Stubenberg, Fiat Germany’s press spokesman, admitted he is aware of four cases in which gas escaped from a valve on one the three gas tanks secured to the Multipla’s underbody. Oxidation occurring on the valves caused small amounts of gas to leak out.The valves on 108 further vehicles have already been checked and exchanged by Fiat, said Stubenberg, and the company will check all 28,000 Multiplas registered in Europe as part of a recall.“While we respect people’s fears, the danger for passengers is slight,” he said. He went on explain that an added scent meant any gas leaks could be immediately detected by the owner, who should then leave the vehicle immediately. Stubenberg said that 2,500 Fiat Multipla Bi-Powers were currently registered in Germany.The risk of explosion or backfiring in methane-powered vehicles cannot be ruled out categorically, insisted Wilfried Hennig, an engineer at a technical centre operated by the ADAC, Germany’s largest motoring club, in Munich: “There is definitely a danger of explosion with this kind of gas concentration.”That is demonstrated regularly by gas explosions, the power of which can demolish houses. He said, although the risk is no greater than with petrol- or diesel-driven vehicles. Extrapolated to all traffic, the number of vehicles powered by methane is in any case very small, he said. All in all, Hennig sees a minimal hazard potential.Hennig takes issue only with the fact that Fiat has failed to issue any detailed instructions in the event of a gas leak, describing the omission as “sinfully negligent”. The owner, the fire and breakdown services should all have been informed, he feels. Fiat’s pressman admits there have been errors: Stubenberg: “We obviously have to clear up this matter.”Wolfgang Scholz, a spokesman for Opel in Ruesselsheim, stresses the tougher safety regulations for methane-powered vehicles, which are considerably stricter than those governing vehicles powered by conventional fuels.By the time each Opel Zafira CNG has reached the showroom from early 2002 it will have been tested three times. “I know of no case in which a vehicle’s gas tank has exploded in normal circumstances,” said Scholz. Even crash tests had failed to puncture the tanks.There are six different methane-powered vehicles currently available on the German market. Four of them are termed bivalent vehicles because they can run on both natural gas and petrol.Besides Fiat’s Multipla Bi-Power, the Ford Focus estate CNG, VW’s Golf Variant and Volvo’s V70 Bi-Fuel are also in the methane-and- petrol market. Opel’s Zafira CNG and Fiat’s Multipla Blupower, meanwhile, occupy the “monovalent” segment of vehicles which operate solely on methane.Other carmakers are planning the move to gas-driven cars in 2002, among them Mercedes and BMW. It may also become possible to convert some models later.Methane-powered vehicles are growing in popularity, according to the Federal Office for Motor Traffic (KBA) in Flensburg, because natural gas is up to 60 per cent cheaper than petrol. The tax rate on the gas has been fixed until 2009 and is independent of the regular raises on other fuels introduced by the government.In addition, energy suppliers are winning customers for gas cars with petrol vouchers and other enticements to offset the higher cost of the vehicle. At present there are around 230 petrol stations in Germany offering natural gas.
