Environmentalists and academics cautiously welcomed the likely return of diesel passenger cars, but a luxury-car dealer said it would be fortunate if his company could find a model that matched the new emissions standard by the end of this year. Chong Got, managing director of Audi's distributor, Premium Motors, said Audi's factory in Europe would produce 20 diesel engine models this year meeting the Euro-V diesel emissions standard. However, they expected only one could meet the emissions standard of a Euro-V petrol car. 'It is not impossible to impose a petrol car's emission standards on a diesel car. The problem is whether the manufacturers would want to alter the engines for you when their efforts mean only a boost in sales of several hundred more vehicles.' In September, Volvo said it had created a Euro-V diesel engine as clean as Euro-VI. Bluetec, a green technology for luxury performance vehicles introduced by Mercedes-Benz, meets even the most stringent Californian diesel emissions standard, but the configurations do not match the requirements in Hong Kong. Crown Motors, the dealer for Daihatsu, Lexus and Toyota, is also searching for qualified models, with a sales manager saying the company would try Europe if it failed to find anything in Japan. Edward Lau Che-feng, director of Friends of the Earth, said it was time the public and government adopted an open mind towards diesel cars with the latest emissions-control technology. However, the government should increase the phasing out of outdated diesel vehicles at the same time. 'Let us be open-minded ... we might fine-tune our strategy, giving more weight to a car's fuel efficiency and climate-friendliness without significantly compromising air quality,' he said. Dennis Leung Yiu-cheung, a mechanical engineering professor at the University of Hong Kong, believed that the most advanced diesel cars would have minimal additional impact on air quality. 'There should be little problem, as most private cars are not used as frequently as diesel buses and trucks,' he said.