Paris: Tougher European car emissions tests being introduced in the wake of the Volkswa-gen scandal are about to bring surprising consequences: bigger engines.
Carmakers that have spent a decade shrinking engine capacities to meet emissions goals are now being forced into a costly U-turn, industry sources said, as more realistic on-the-road testing exposes deep flaws in their smallest motors.
Renault, General Motors and VW are preparing to enlarge or scrap some of their best-selling small car engines over the next three years, the people said. Other manufacturers are expe-cted to follow, with both diesel and petrol affected.
The reversal makes it even harder to meet carbon dioxide (CO2) targets and will challenge development budgets already stretched by a rush into electric cars and hybrids.
“The techniques we’ve used to reduce engine capacities will no longer allow us to meet emissions standards,” said Alain Raposo, head of power train at the Renault-Nissan alliance.
“We’re reaching the limits of downsizing,” he said at the Paris auto show, which ends on Saturday. Renault, VW and GM’s Opel all declined to comment on specific engine plans.
For years, carmakers kept pace with European Union CO2 goals by shrinking engine capacities, while adding turbochargers to make up lost power.
These mini-motors sailed through official lab tests conducted - until now - on rollers at unrealistically moderate temperatures and speeds. Carmakers, regulators and green groups knew that real-world CO2 and nitrogen oxide (NOx) emissions were much higher, but the discrepancy remained unresolved.
All that is about to change. Starting next year, new models will be subjected to realistic on-the-road testing for NOx, with all cars required to comply by 2019. Fuel consumption and CO2 will follow two years later under a new global test standard.
Independent testing in the wake of VW’s exposure last year as a US diesel emissions cheat has shed more light on the scale of the problem facing automakers.
Carmakers’ smallest European engines, when driven at higher loads than current tests allow, far exceed legal emissions levels. Heat from the souped-up turbos generates diesel NOx up to 15 times over the limit; gasoline equivalents lose fuel-efficiency and spew fine particles and carbon monoxide.
“They might be doing OK in the current European test cycle, but in the real world they are not performing,” said Pavan Potluri, an analyst with influential forecaster IHS Automotive.
