Audi Developing New Variation on the Hybrid

We’ve heard U.S. and European efficiency mandates will force automakers to develop new technologies over the next decade and beyond, while we’ve also heard “the internal combustion engine will continue to assume primary importance in the automobile for a long time.”

While many industry observers have said this of traditional engines, the above quote comes from Audi which is working on a next evolutionary step for “future” internal combustion solutions beyond stop-start systems called iHEV along with complementary fuel-saving technologies.

This Intelligent Hybrid Vehicle system, as its maker calls it, goes beyond shutting off an engine to save fuel at a stop as is the case with stop-start systems, and allows a conventional petrol engine to either idle or shut off completely while the car is coasting to reduce or eliminate fuel usage.

The effect would be very much the same if you were driving down a grade or even a level section, and realizing you had enough kinetic energy to keep coasting, you briefly put the car in neutral, switched off the key and let momentum and possibly gravity do the work. While that practice is not at all recommended, Audi is developing software and controls to automatically allow a car to safely and reliably do something akin to this and more.

Audi’s A7 Sportback 3.0 TFSI iHEV has been used to demonstrate the system which relies on an unconventional 48-volt electrical system incorporating a powerful starter motor and high-cycle-strength 48-volt lithium-ion battery located in the trunk.

The potentially networked system is very intelligent and takes myriad data into consideration to generate a seamless driving experience, according to Autocar, which briefly tested the system.

iHEV works in conjunction with Audi’s PEA (Predictive Efficiency Assistant) which takes info from the navigation system such as local speed limits, road gradient data, info from road signs and predicts what’s coming as it communicates to the driver fuel saving driving suggestions.

When the driver takes the suggestion to step off the accelerator, the iHEV system may then turn off the engine for the duration in which its power input is not needed. One example of when this could be done is when coming to a reduced speed zone in which the car could coast down. The system takes into account data such as tire and aerodynamic rolling resistance, the car’s speed and road gradient to make anyone into the ultimate hypermiler.

Even if a vehicle were to tow a trailer or add on a roof-top box, extra drag could be calculated into the system now under development.

Another technological helper is Active Cruise Control which could be used with PEA. Audi says the car can take over throttle and brake controls, and the iHEV system could turn off the engine or brake as needed to maximize efficiency.

In an interview with Autocar, Audi said with the engine idled, the A7 could coast further than 0.62 miles (1 km) when traveling on a level grade.

Audi’s press release on this and other “future engines” says the A7 Sportback 3.0 TFSI iHEV has completed a 61 km (37.90 mile) stretch of winding country roads north of Ingolstadt several times, with a normal, everyday style of driving, and returned impressive results.

With the PEA system turned off, the driver covered 28 percent of the route with the engine switched off. Once the PEA system was activated, this figure rose to 43 percent; at the same time, fuel consumption dropped by around 10 percent, yet Audi says the driving time increased by only two minutes (three percent).


  • DownUnder

    Toyota must feel the heat now from Audi.
    BTW, Toyota just beat Audi in the FIA World Endurance Championship.
    ” . . . Thanks also to Audi for a clean fight; we really enjoyed competing with them and they were very fair. We have huge respect for them and what they have achieved over the past decade and more; to beat such a strong opponent has not been easy. It’s not only a fantastic result for Toyota Racing, it also shows how exciting the FIA World Endurance Championship is. We know Audi will come back strongly in the next races so we are looking forward to continuing our close, and genuinely friendly, rivalry.”

  • jayzz

    Isn’t it a shame that after all those of years of campaigning against hybrids, the likes of audi and volkswagen have finally realised the need to move ahead in engine tech, specifically twin power source engines.

    I would ask Audi to lose the crap eHEV iHEV crap and just call the designs Hybrids. Really there is no point in pretending the designs are different to the other hybrids. Consumers these days are very well informed and know how to quckly grasp differences.

  • Mike Stevens

    Lets see, extra cost for the system, with 3% time penalty vs only 10% fuel savings?

    A long run for a short slide!

  • perfectapproach

    Lets see, extra cost for the system, with 3% time penalty vs only 10% fuel savings?
    A long run for a short slide!

    I’m gonna agree with ya there. They’re squeezing every little bit of efficiency out of an internal combustion engine when the reality is that big electric motors/batteries are much more efficient. The research has (mostly) already been done, and the cost for this new system will likely outweigh the benefit it provides. This might make for a good system to control an ICE in a true hybrid setup, but with only the ICE pushing the car, it’s almost a waste of time.

    I do also recall that Mazda was doing something like this with their SkyActiv technology. Again, good way to control an ICE in a hybrid setup, but without an electric motor providing some of the motive force, it’s wasted effort.

  • SteveC

    What is the big deal? My Toyota hybrid has been shutting the engine off when I’m coasting for many years now. This is silly. I’m not a big fan of Audi. I think their cars are very ugly and they seem to think everything they do is big news even if they are several years behind. My $.02

  • JD

    Oh my gosh, Audi perfected the Chevy Malibu Eco or did they?

  • MS

    I’m not seeing here any hybrid .

    This VW is all about marketing, they take the stop and start concept and join the dual clunch and call it hybrid.

  • Shines

    Wasn’t the first Malibu microhybrid using a bigger starter motor and the larger battery? This sounds like the same thing but without the regenerative braking. So you have a bigger battery that could use the energy that will be wasted as heat when this Audi brakes, which means the alternator will have to work harder to recharge the larger battery. Without the regenerative braking it is like a cheap microhybrid. Add the regenerative breaking and then you have something close to the eAssist in GM cars already on the road.