There have been tests using a Valeo electric supercharger to augment the existing traditional exhaust-driven turbocharger on a Ford Focus. The firm Ricardo was able to increase gas mileage from 39 to 59mpg in European test cycles.
It doesn't really result in an increase in real-world performance, since it doesn't help the top end of the power curve, but gives a big jump to stop-and-go performance.
For the confused: this article is about electrically-driven pre-compressors ("turbochargers") rather than the Tesla electric battery fast-charge EV station and service.
The canonical use of the term "supercharger" in the automotive context is to describe a compressor that is driven directly from a reciprocating engine's drive output. They date back to the very late 1800s and early 1900s in various applications on internal combustion engines, and made it in to production automobile engines in the 20s.
A turbocharger, by contrast, uses waste exhaust energy to drive a compressor. A turbocharger is actually considered a type of supercharger. The full name -- although rarely used -- is actually turbosupercharger.
Not to detract from your clarification, but I think it's important that any interested readers understand that Tesla hijacked the term to describe their electric charging stations.
Mercedes F1 uses a similar concept they separated the hot and cold parts of the turbo and connected them with a long shaft. The vehicle is a hybrid and uses the battery to spin up the turbine at low speeds when there is less exhaust.
This is very different than the systems used in an F1 car. Mercedes' innovation of splitting the hod/cold parts of the turbo was ingenious, but it really has nothing to do with Volvo's system.
In an F1 car, the system is far more advanced. The MGU-H is a combination motor/generator that is attached to the primary shaft of the single turbocharger used in the F1 engine system. This is the most direct way to use electric power to assist in turbocharging, but my understanding is that the MGU-H involves some pretty exotic construction in order to withstand the environment in which it operates. Basically, they're far to expensive to use in a road car.
Volvo's system is entirely different. Volvo uses two normal turbochargers that are attached to the engine's exhaust, just like you'd normally expect. Based on the descriptions I've read, and details aren't exactly bountiful, the Volvo system actually uses the electric supercharger to force air in to the turbine side of the turbochargers, not the compressor as I originally expected.
This is in stark contrast to the F1 system where the electric motor/generator is an integral part of the actual turbocharger. I'm pretty puzzled by Volvo's system. I would have expected them to use the electric supercharger to generate intake pressure directly, which would require the e-supercharger to be plumbed in to the compressor circuit of the turbochargers.
The problem with this setup would be that it would create back pressure on the compressors attached to the turbochargers, which isn't optimal. It's not the end of the world, but it's counter productive, so Volvo's approach is pretty inventive. I wonder how efficient it will be though. They're literally going to use an e-supercharger to drive the turbochargers through the exhaust circuit. Pretty nutty, but I like it!
Or you save yourself the effort for all these widgets, use a proper battery and purebred electric motors and get the fastest sedan in the world pretty much effortlessly.
If theres one thing electric propulsion doesn't need then its all the nonsense we put on top of combustion engines to smooth out their power curve.
There's two camps when it comes to automotive performance - those who care only about performance as a means to an end, and those who care about the journey to performance.
For example, dual clutch automatics have been better than manual transmissions for quite awhile now in terms of shift speeds, but those of us who still enjoy the journey prefer manual shifting for the pure pleasure of being directly connected to the car.
The same holds for internal combustion engines and that quality that several thousands of explosions per second bring to the table. The almost-silent whine of an electric motor may have an amazing torque curve but it will never invoke the primal feeling of a revving V8.
I suspect if you could drive a 2,000+ HP turbine hybrid you would quickly change up your mind about optimal sound / smell ect. Advantage being electric gets you past the power lag from revving a turbine, gas gets you past the battery power density issues, and the turbine gets you past the HP/lb limitations of a v12. However, while doable nobody seems to be building that beast.
Meh, it all sounds like self-indulgent crap. I mean, I've always considered things like the Harley Davidson nothing less than butt jewelry, and direct A->B performance along an energy scale is pretty much all that matters to me. Electric can be boring as hell for all I care; in fact, all transportation 'culture' should be eschewed, so we can finally just transpose our civilizations away from the wasteful hedonism that is your modern auto-industrial society.
Now, if you want to argue that it is an Art form, then yes, I'm all there. I'd sure love to know what a 3D-printed Sportster rode, like ..
Yes, absolutely - many people merely want transportation and are thrilled with their Toyota-made appliances.
Thankfully that option is available to you, while those of us interested in other factors have additional options.
I would actually agree that a Harley is more about being loud than fast, and that rolling refrigerator I mentioned earlier would likely trounce my old musclecar in most measurable performance tests, except perhaps driving enjoyment.
I'm a total gear head, and I love the sound of a V8. I drive an S65 (4.0L V8 with an 8,300 RPM redline) powered M3 because I love the sound of its engine at 7,000+ RPM.
I also cannot wait for super-performance electrics, and I'm a huge Tesla fan. I even dedicated a portion of my investment portfolio to TSLA, in spite of all the analysts warnings that it's overpriced. I believe electric is the future, and I can't wait.
I like anything with four wheels that goes fast! I don't care if its powered by a petrol engine, a diesel engine, or an electric motor.
However, the parent poster has mischaracterized the current circumstances in a pretty bad way:
> Or you save yourself the effort for all these widgets, use a proper battery and purebred electric motors and get the fastest sedan in the world pretty much effortlessly.
There is a difference between fastest and quickest. The Model S P85D is crazy fast to 60 MPH, but if you're interested in the whole truth, you don't stop looking at 60 MPH. You also ask why the P85D is so fast to 60. First, it has a ton of torque available at a full stop, and secondly, it has AWD, which is just about the only way you move a car this weight to 60 MPH that quickly.
Once you go beyond 60 MPH, the P85D doesn't shine nearly as brightly. I'll use Motor Trend's numbers for comparison here, in an effort to be consistent. Quarter-mile elapsed-time and trap speed are great indicators of a cars overall acceleration and speed performance, because you have to accelerate quickly and continue to generate power in order to achieve a high trap speed..
Model S P85D: 11.6s @ 115 MPH [1]
Mercedes E63 AMG: 11.6s @ 121.8 MPH [2]
BMW M5: 11.9s @ 122.2 MPH [2]
It's worth noting that the Mercedes is AWD, but the BMW is not. The P85D is extremely quick, but by the time it reaches the 1/4 mile mark, it is losing ground to both of its petrol powered competitors in a big way. A difference of 7 MPH in trap speed is a really big difference.
So, if we look at the super-sedan market, we can see that there's more to it than 0-60 times. Yes, theres a very sound argument that none of this matters for the street, because you'd be a lunatic to unleash any of these cars' capabilities on a public roadway. But that's not what we're talking about. We're talking about the current state of performance, and electric still has a ways to go if you're talking about the entire performance spectrum, not just 0-60 (which is a very limited metric).
I do believe that all-electric is the ultimate destination, but I'm not certain chemical batteries will be with us for the long haul. I also believe the good ol' ICE (internal combustion engine) still has some legs. Turbocharging small displacement ICEs is a very effective way to generate lots of power without adding a lot of weight (batteries are extremely heavy, btw).
The problem with turbocharging a small ICE with insane levels of boost is that they're not very tractable. To generate lots of boost, you need a big turbo. A big turbo takes a lot of exhaust energy to spin up, and that means you get poor low-RPM power and responsiveness. Electric superchargers are a great way to solve this problem... As is a smallish battery and a supplementary electric motor (vis a vis BMW i8, Porsche 918, McLaren P1, etc). And round and round we go.
Gas beats the energy of density of batteries by a huge margin. That alone is reason to continue work on traditional combustion engines and/or hybrid cars.
Battery technology will continue to improve, and can already quick charge a vehicle in ~30 minutes. There are very few applications that require charging faster than that, or where you can't charge your vehicle at night.
It doesn't really result in an increase in real-world performance, since it doesn't help the top end of the power curve, but gives a big jump to stop-and-go performance.
http://blog.caranddriver.com/blowing-your-way-to-savings-how...