Superchargers expand -- slowly -- beyond high-performance niche
The supercharger -- traditionally consigned to a niche of high-performance cars -- is getting a second look as a fuel saver.
Eaton Corp., the world's leading supplier of superchargers, says it has a production contract from an unnamed global automaker that plans to pair Eaton's TVS supercharger with a turbocharger to boost a small engine.
The powertrain will enter production in 2013 or 2014, said Ed Lunder, Eaton's product strategy manager.
Lunder says the customer is not Volkswagen AG, which introduced a 1.4-liter engine paired with a turbocharger and an Eaton supercharger at the 2005 Frankfurt auto show.
VW's Twincharger engine has powered a number of small and mid-sized vehicles.
Superchargers vs. Turbos
Superchargers and turbochargers boost an engine's power by forcing additional air into the intake manifold.
Turbochargers, which are powered by the vehicle's exhaust gases, allow automakers to downsize the engine without sacrificing power. But acceleration is modest at low engine speeds.
Superchargers, in contrast, can provide instant acceleration at low engine speeds. But they draw their power via a belt from the engine itself, causing parasitic energy losses.
In theory, a twin-charging system - that is, an engine powered by a supercharger and turbo - could combine the best attributes of each with the supercharger providing quick acceleration at low speeds and the turbo taking over at high speeds. But a twin-blower system adds cost and complexity.
Though VW's Twincharger has won awards for design, VW plans to replace it in the coming years with an engine that has a turbocharger but no supercharger.
The new engine has been optimized so that its turbocharger can spool up quickly, even at relatively low rpms, according to a VW spokesman.
For now, turbochargers appear to be the auto industry's dominant blower technology.
According to analyst Jeff Jowett of IHS Automotive, automakers in North America are expected to produce 2.2 million vehicles with blowers this year, and the vast majority are turbochargers.
Honeywell Turbo Technologies and BorgWarner Inc. dominate the turbo market, but Germany's Robert Bosch GmbH and Continental AG are muscling into the segment.
Superchargers have been largely reserved for high-performance vehicles. Eaton's TVS supercharger has been used on the Chevrolet Corvette ZR1, the Cadillac CTS-V, the Lotus Evora S and the Shelby Mustang GT500.
But Eaton now promotes the supercharger as a fuel-saving technology, and automakers are considering its merits.
Nissan Motor Co. uses an Eaton supercharger on its 1.2-liter three-cylinder engine in the Micra. It also displayed a supercharged engine in the Ellure concept, which debuted at the 2010 Los Angeles Auto Show.
The Ellure's hybrid powertrain features a 2.5-liter, four-cylinder engine plus an electric motor powered by lithium ion batteries.
Nissan described it as "a conceptual preview" of future powertrains, and billed it as part of a future range of fuel-efficient vehicles.
Meanwhile, France's Valeo SA is developing an electrically driven supercharger that would eliminate the traditional belt drive.
Pierre-Emmanuel Strohl, product marketing director of Valeo Powertrain Systems, says the company has a contract to produce it in 2015. He did not disclose Valeo's future customer.
So will superchargers find a niche as a fuel-efficient technology?
"I think there's potential, although the higher volume will be in turbos," said Jowett of IHS. "I think it's wait and see. CAFE is going to get really tough, and we'll see a lot of out-of-the-box thinking."
You can reach David Sedgwick at email@example.com.