Navigant Research Blog

Turbocharger Suppliers Have a New Market to Pursue

— June 25, 2015

The recent Navigant Research report Automotive Fuel Efficiency Technologies concluded that one of the main approaches to delivering better fuel economy for cars is to downsize existing engines but coax more power out of them. The principle of increasing air pressure at an internal combustion engine intake to produce extra power is well-established and is known generically as forced induction. The two main mechanical types of forced induction are usually defined as:

• Turbocharging, where the compressor is driven by exhaust gases; and
• Supercharging, where the compressor is driven directly off the engine crankshaft

Turbochargers are well known for being a relatively simple way to get more power from a small engine, but also have the disadvantage of lag because the maximum boost is not available until the engine speed is high. Superchargers can be set up to provide boost at low engine speeds, but they also use power when they are not needed, and so they can adversely affect fuel economy under normal driving conditions.

A third variant, electric turbochargers, now looks set to hit the market. An electric turbocharger offers an engine boost on demand without the lag of an exhaust-driven component or the physical drag that a supercharger places on the engine. The technology operates from electrical energy that is recovered by regenerative braking, and takes advantage of the fact that electric motors develop their maximum torque immediately from a stationary position.

The concept has been under development for some years, and the biggest challenge so far is to get enough usable power from a 12V electric motor. However, with the imminent rollout of 48V electrical subsystems for advanced stop-start systems (as discussed in detail in the Navigant Research report 48-Volt Systems for Automotive Applications), it will become practical to implement an electric turbocharger for the first time. Audi is the only manufacturer to announce a planned launch so far, but most other manufacturers are thought to be working on similar concepts.

Other Suppliers

French Tier One supplier Valeo is one of the first to offer a production-ready electric turbocharger. The company acquired the switched reluctance motor technology from U.K.-based Controlled Power Technologies in 2011. The motor is liquid-cooled and the 48V system needs additional power electronics and a bigger battery than normal, so there are additional costs to consider. Benefits include improved performance as well as better fuel economy, so manufacturers are expected to be able to charge a premium.

Conventional turbocharger suppliers are also developing electric products. BorgWarner offers electric turbocharging in its eBOOSTER system, which has been tested on both gasoline and diesel engines. Honeywell is another well-established supplier of conventional turbochargers, and is thought to be developing an electric version for introduction in a couple of years’ time. As is often the case, emerging technology stimulates innovation from brand new companies as well as established suppliers; one example is U.K.-based Aeristech.

Fuel efficiency is a key focus for automotive manufacturers that want to avoid financial penalties for missing emissions targets in the coming years in many countries around the world. Incremental improvements of 1%–2% may not be enough, so investing in technology that has the potential to deliver significant fuel economy increases without sacrificing performance or drivability may be money well spent. Electric turbocharging looks likely to be the first application that will launch 48V systems into series production, a shift brings with it many other benefits of electrification that will challenge hybrid technology at a much lower price point.


Uber-CMU Deal Highlights Transition of Autonomous Technology

— June 16, 2015

FT_Advisory_webIn February 2015, Uber and Carnegie Mellon University (CMU) announced a strategic partnership to develop autonomous driving technology. It caused a bit of a stir in the auto industry because until that time Google was the only non-automotive company that had put serious effort into advancing automotive technology. Uber, however, identified a technology that could make a big difference to its bottom line in the long term and had decided to become an active participant in the engineering.

Then, in May, an article in The Verge claimed that Uber had gutted CMU’s robotics lab. Within a week or two, more articles were published about how Uber had “poached” staff and that CMU was “in a crisis”—all very dramatic. It turns out that Uber had indeed opened its own engineering center in Pittsburgh, just up the road from CMU, and that a good number of engineers and scientists had been given lucrative offers to work there.

CMU, however, seemed somewhat less excited about the situation than the journalists. Gradually, more reasoned articles made it into print, pointing out that there are many other more positive aspects to this story. Yes, Uber had diverted a large chuck of the CMU staff to work full-time on its autonomous vehicle project, but CMU enhanced its reputation as the source of advanced robotic development work. Additionally, the City of Pittsburgh has the potential to challenge Silicon Valley as an alternative site for automotive innovation. (It probably doesn’t hurt that SAE International is also based nearby.)

Universities have always been at the forefront of the latest technology development, and their role is usually to then spin off and partner with commercial companies that can take concepts into production. This is precisely what is happening now in Pittsburgh—another indication that autonomous driving is close to entering production and becoming a reality. There are plenty of new challenges for CMU to explore, and the establishment of an advanced automotive engineering center in Pittsburgh can only be good for the future because it will attract talented researchers who eventually want to end up in high-paying jobs.


Supercar Launches Reveal Advanced Automaker Thinking

— February 2, 2015

Ford and Honda both announced supercars at this year’s Detroit Auto Show.  It’s worth taking a look at some of the key features in each of these vehicles to gauge where automotive technology is headed.

Ford GT

Originally developed in the mid-1960s, the Ford GT won the 24 Hours of Le Mans race for 4 consecutive years from 1966 through 1969.  At the 2002 Detroit Auto Show, a concept car was shown that captured the look of the original racing car but made it practical to own and drive on regular roads.  Slightly more than 4,000 Ford GTs were produced in model years 2005 and 2006.

Now a new version has been unveiled.  Beginning production in late 2016, the GT will be available in select global markets to celebrate the 50th anniversary of Ford GT race cars placing 1-2-3 at the 1966 24 Hours of Le Mans race.  Although its predecessors all featured V8 engines, the newest version will be fitted with a twin-turbocharged EcoBoost V6, producing more than 600 hp.  Ford is keen to show that its chosen path of downsizing engines for fuel economy still offers plenty of power.

Low weight is an important factor for production vehicles as well as race cars, and the new GT has a carbon fiber passenger cell with integrated seats and aluminum front and rear chassis sub-frames encapsulated in structural carbon fiber body panels.  The exterior shape minimizes drag and optimizes downward forces.  An active rear spoiler is used for control of braking, handling, and stability at speed.  Carbon fiber is a very important material for light vehicle structures, and the new GT will give Ford some practical experience in production.  Ford also announced at the show that it has formed a joint venture with DowAksa (itself a 50:50 joint venture between Dow Chemical and acrylic fiber supplier Aksa) to develop carbon fiber for mass-market vehicle applications.

Acura NSX

The original NSX, developed by Honda (though badged as an Acura in North America) from 1989 through 2005, sold more than 18,000 vehicles over 15 years.  The model has always been a showcase for the latest Honda technology, and the company is now relaunching the NSX as a reminder of its latest technology developments.  Production is slated for summer 2015, with first deliveries before the end of the year.

Like the Ford GT, the NSX features advanced V6 engine technology (Honda has never offered a V8 engine in its consumer vehicles despite developing one for racing use in Indy cars and Formula One).  The new NSX will feature a twin-turbocharged V6 engine with a 9-speed dual clutch transmission and Honda’s Sport Hybrid system, which uses three electric motors to boost power and enhance handling – one at the rear and one at each front wheel.

Managing airflow is again a priority, and Honda engineers have carefully tuned the vents and air intakes for maximum efficiency.  The first-generation vehicle used all-aluminum construction for light weight, but the new model has a space frame design consisting of an internal aluminum frame reinforced by ultra-high strength steel, all anchored by a carbon fiber floor.  Body panels are made of a combination of aluminum and sheet molding composite.  Suspension members are all cast aluminum.

Both of these supercars come from mass-market manufacturers that want to showcase their advanced technology. As my colleague Sam Abuelsamid observes, they manage to demonstrate a combination of high performance and fuel efficiency.  When the time is right, some of the processes, design concepts, components, and materials will make their way into high-volume production.


Schaeffler Shows One Path to Better Fuel Economy

— January 30, 2015

January in Detroit heralds the annual North American International Auto Show (NAIAS), where many manufacturers launch new models and technology.  It’s less well known as a supplier event, but many of the Tier One companies hold press and industry events to showcase their developments, primarily during the media and industry days that are held before the show opens to the general public.

This year, German supplier Schaeffler chose to highlight its project on fuel economy, with a view to meeting the upcoming more stringent American CAFE requirements.  As well as developing specific components and products, the company has incorporated them into an existing vehicle to demonstrate the integration potential.  Phase 1 of the implementation shows one way to meet the 2020 CAFE target on an existing vehicle by making a series of small, low-cost changes; Phase 2 will add additional features to meet the 2025 fuel economy goal.

Hunker Down

The target vehicle chosen was a model year 2013 Ford Escape AWD (all-wheel drive), which features a 2.0-liter engine and Ford’s 6-speed automatic transmission.  For phase 1, Schaeffler engineers implemented an AWD disconnect feature to eliminate additional friction when only two-wheel drive is necessary, a new torque converter damper to allow a lower lockup speed, and an automatic engine stop-start system.  A new thermal management module enabled faster engine warming from cold.  Other detail changes included coated tappets, new balance shaft bearings, and low rolling-resistance tires.

To reach the 2025 target fuel economy, phase 2 houses two main features: ride height adjustment and disconnecting vehicle accessory drives from the engine.  Automatically reducing the ride height as speed increases is a straightforward way to reduce aerodynamic drag, a topic that I discussed in a previous blog.  The idea of disconnecting accessory drives has been around for some time, and is key to extending the value of stop-start systems, but replacing a traditional crankshaft belt drive with individual electric motors is a very expensive solution.

Clutch Move

Schaeffler solves this dilemma by setting up a separate 48V motor generator to power the accessories when the engine is switched off.  The system is controlled by a pair of clutches that can connect the electric motor to either the engine or the transmission.  Using a 48V subsystem allows more powerful regenerative braking than a 12V system, and therefore greater energy recovery, and the motor can also be used to supplement the drive.

Navigant Research has recently released a detailed report on this topic: Automotive Fuel Efficiency Technologies.  The Schaeffler approach nicely illustrates our conclusion that there is no single solution for meeting future fuel economy targets, and future vehicles will have to incorporate many small changes that will combine to deliver measurable results.  Schaeffler’s concept of creating a separate 48V accessory drive subsystem can keep costs manageable while allowing the industry to transition from 12V to 48V.


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