BorgWarner eTurbo Promises to Eliminate Lag

BorgWarner has long been a leader in turbochargers. More recently it has jumped (big time) into electrification technologies.

BorgWarner eTurbo. (Image: BorgWarner)

Now it’s combining the two with its new eTurbo hybrid technology. The supplier plans to launch production of the system in 2022 with an unnamed European OEM.

No other details about the contract were provided. But BorgWarner, which derives about 27% of its sales from traditional turbos, says it’s a big deal.

"We believe this is the largest industry award to date for this type of technology and is an important milestone for our company," asserts Joe Fadool, who heads the company’s Emissions, Thermal and Turbo Systems.

More Boost, Less Lag

The eTurbo teams a mechanical turbocharger with an electric motor directly connected to the shaft, allowing it to act either as motor or a generator. It must be paired with either a 48-volt mild or full hybrid system.

Compared with current turbochargers, the electrified boost is said to provide:

• A more than 200% improvement in transient boost response
• 50% less “time-to-torque,” virtually eliminating turbo lag
• “Exceptional” low-end torque

In addition, BorgWarner says the electric turbocharger can capture excess turbine energy to generate electrical power and reduce emissions through aftertreatment management and precise air/fuel ratio control. It also can help drive on-demand exhaust gas recirculation by increasing engine backpressure to reduce emissions.

Maximizing Downsizing

Turbochargers enable carmakers to use smaller engines, improving fuel efficiency without sacrificing performance. Electric units promise to take this to the next level (dare we say downsizing on steroids, or perhaps superminimizing?).

For example, BorgWarner says eTurbo could allow a 2.0-liter 4-cylinder engine to replace a 5.0-liter V-8, providing the same power with a 25% gain in efficiency.

In an off-highway commercial vehicle, a 6.0-liter engine coupled with eTurbo could do the job of a 9.0-liter unit, according to the supplier. Adding an electric assist hybrid system could take engine size all the way down to a 4.5-liter mill.

Another benefit: eTurbo can capture and convert excess exhaust energy to power accessories or charge the battery. This could enable the use of smaller batteries.

Trending Applications

Other companies also are getting in on the action. Rival Garrett Motion, which was spun off from Honeywell, plans to launch its electric turbocharger in 2021. And several carmakers—including Audi and Mercedes-Benz—offer electrified turbochargers that act more like electric superchargers.

BorgWarner’s first application is for a passenger vehicle. The company notes the technology is particularly well-suited for Miller Cycle engines (a variant of the Atkinson), that closes the intake valve later than usual to help boost power and efficiency.

The company also plans to adapt eTurbo to commercial vehicles and possibly off-highway, marine and stationary power applications.