Valeo says Audi will use its supercharger to reduce lag and save fuel

PARIS -- Valeo says other automakers likely will follow Audi in using its electric supercharger that boosts an engine's acceleration while also saving fuel. The French supplier said Audi will launch a production car with the supercharger next year. It did not name the model but reports have said it will be offered on the Audi Q7 premium SUV.

Other automakers are testing the supplier's technology, Valeo's Chief Operating Officer Christophe Perillat-Piratoine said, without specifying.

Valeo's electric supercharger eliminates the lag time in the acceleration of cars with turbocharged engines. Unlike a turbocharger, which runs off exhaust gases, Valeo's system uses an electric motor to give the engine a near instantaneous flow of air to boost acceleration.

Valeo says the system can reduce fuel consumption by 7 percent to 20 percent. A downside is higher costs and increased power consumption.

Perillat-Piratoine said Valeo had a one- to two-year lead over other suppliers in the supercharger technology. “We have created this market and other suppliers will follow,” Perillat-Piratoine toldAutomotive News Europe.

Honeywell, which Roland Berger estimates has a global-leading 34 percent share of the light vehicle turbocharger market, calls the technology an electrically driven compressor, or an e-charger. The supplier expects to have its version of the system on the market between 2017 and 2019, Gavin Donkin, Honeywell Turbo Technologies vice president for product development, told Automotive News Europe.

Donkin said that because e-chargers use an electric motor to drive a separate compressor the system is not held back by the physics of exhaust gases. “You can have very, very good transient response [very little turbo lag] at the low end of the engine speed,” Donkin said.

The reduction in turbo lag allows power to be used at lower RPM, which should improve fuel economy and offer a “noticeable gain in drivability,” said Andrew Wrobel, a senior analyst for IHS Automotive. “Similar systems have already been tested on racecars in the LMP1 series, with good success,” he said.

Valeo's electric supercharger will largely compete against hybrid powertrains that use electric motors to mitigate turbo lag, Wrobel said. Performance hybrids such as the McLaren P1, Porsche 918, Ferrari LaFerrari, and the lower-cost Acura NSX use or will use a hybrid system to boost the performance and increase the fuel economy, even though the true fuel-saving benefits are arguable and vary based on the tuning of the powertrain, Wrobel said.

“Systems similar to these hybrid powertrains with electric motors could be used on higher-production, non-performance vehicles tuned more for fuel economy than power and speed,” Wrobel said.

BMW has a system on its i8 plug-in hybrid supercar that serves a similar function to Valeo's supercharger. "The BMW i8 has a starter-generator that is able to output 11 hp and 38 foot pounds (51.5 newton meters) during engine startup,” said BMW spokesman Matthew Russell. The starter-generator's output is used to offset perceived lag from the relatively large turbocharger fit to the i8's 1.5-liter three-cylinder gasoline engine, he said.