Bosch claims a 'breakthrough' that could save diesel engines

Robert Bosch said its engineers have developed a diesel exhaust system that cuts emissions far below legal limits taking effect in 2020 and can help automakers avoid potential driving bans in Europe that threaten to doom the engine technology.

“This breakthrough offers the opportunity to shift the heated debate over diesel into new territory and, hopefully, bring it to a close," Bosch CEO Volkmar Denner said Wednesday at a press conference outside Stuttgart.

The German engineering giant, the biggest supplier of diesel engine technology to global automakers from Volkswagen to General Motors to Fiat Chrysler Automobiles, is stepping up the fight against eroding market share sparked by VW’s 2015 emissions cheating scandal.

While tens of thousands of jobs hinge on the technology, customers increasingly are opting for gasoline engines as cities such as Paris and London consider imposing driving bans to improve air quality.

Automakers have relied on diesel to help the industry meet limits on carbon dioxide emissions, a contributor to global warming. But while it emits less CO2 than gasoline-fueled engines, the technology generates nitrogen oxides that help create harmful smog, a problem most acute in big cities.

Bosch’s new process optimizes thermal management of exhaust temperatures, slashing nitrogen oxide emissions to one-tenth of the legally permitted limit, and doesn’t require new hardware, Denner said. The system keeps emissions stable even at cold temperatures, he said.

“With this new exhaust technology, blanket driving bans in the centers of the world’s major cities will no longer be an issue. Why? Because we now have the technology to resolve the problem of nitrogen oxides in road traffic," Denner said.

Bosch’s role as leading global supplier has come under scrutiny as German prosecutors investigate potentially illegal diesel engine technology used by automakers to pass emission tests.

Denner reiterated that Bosch fully cooperates with the relevant authorities. He called for more transparency in emission tests for vehicles with combustion engines as well as electric vehicles to allow a realistic view of the exact impact on the environment.

He said the company is prohibiting technology that recognizes test cycles, and its products aren’t allowed to be optimized for test situations anymore. Regulators have stepped up efforts to narrow the gap between official emission labels based on lab tests and real driving emissions.