Diesels are here to stay for a 'long time', expert says
But we'll see surge in downsized petrols, plug-ins
Diesels are here to stay for a long, long time, one of Europe's leading engine experts has claimed.
He did so as the fuel came under the microscope for its toxic emissions in the wake of the Volkswagen scandal.
He also forecast that the proportion of smaller petrol engines and the number of plug-in hybrids will increase significantly as carmakers strive to meet more stringent regulatory limits.
The predictions were made by Mr Willi Gelse, the Mercedes engineer in charge of testing engine mechanics.
He stressed how diesel's 15pc/20pc difference in fuel consumption and, presumably, lower cost at the pumps will keep the fuel at the head of the queue for a long time.
Mr Gelse was taking questions in the course of a special-group interview, which included Independent Motors, on the fringes of an international launch.
While he accepted that making diesel engines will become more expensive, he repeatedly insisted that the lower fuel-price and consumption differential would still make it the first choice for many motorists.
There is no doubt, however, that petrol engines will make greater strides, he said. And he was also enthusiastic about plug-in hybrids becoming increasingly common.
But still he came back to his belief that: "The diesel engine will remain for the foreseeable future."
Providing real insight into how a major carmaker views the coming decades - and a preview of the fuel bases for cars being planned - Mr Gelse said the 'ideal' car of the future will be a downsized petrol with direct injection.
"I am convinced we are at the beginning and with direct injection we can improve the combustion process." In other words, he believes engineers can get a lot more mileage out of a litre of fuel.
He also expects diesels to improve substantially as there is, he said, "lots of potential" to do so by downsizing, using special internal technology, etc.
He emphasised that there won't be one great big breakthrough. It will, he says, be "a lot of small things, a lot of new materials. Lots of small steps".
The senior engineer said Mercedes had no plans to make a three-cylinder petrol engine - unlike BMW which already has one. Significantly, however, he didn't rule out a smaller four-cylinder power plant.
And his company is hot on the trail of plug-in hybrid vehicles. They expect to have 10 plug-in models by 2017.
Several other marques are also powering out plug-ins but Mr Gelse made the point a few times that these cars have to be affordable. "Costs have to be kept so that the customer can afford it."
This concern refers to the high cost of producing hybrids and, in many countries, the level of incentive for people to buy one. In Ireland's case, that can amount to €7,500 when VRT rebates and grants are taken into account.
It is obvious from his comments, however, that, despite diesel's predominance, there is a massive renewed focus on petrols. When I asked him what he believed would be the 'engine of the future', notwithstanding his conviction that diesel would play a major role, he unequivocally said: "The engine of the future is a downsized petrol."