[00:01] control. Both feet to the floor, lift on brake. brake. Wow. video, we are talking about electric turbochargers. So, we're going to be
[00:16] focusing on four questions. What is it? How does it work? What are the advantages and disadvantages? And finally, is it a good thing? What's it like to drive? And honestly, this thing is quite unique. I've never driven
[00:28] anything that has felt like this. So, it is a truly unique driving experience. And so, what better vehicle to talk about electric turbochargers than probably the most capable vehicle out there with electric turbos? The new
[00:41] Porsche 911 Turbo S? So, that first question, what is an electric turbocharger, you've got your exhaust side and your intake side. On the exhaust side, you have a turbine that is driven by your exhaust gases that spins
[00:55] up a compressor which is on the intake side to help increase the amount of air going into the engine, create boost, and with that added air create more power using more fuel of course. And so that is the typical system. What we are
[01:07] changing is we are just sandwiching an electric motor between that turbine and that compressor. So now you have two sources of spinning up the compressor turbocharger. You have the electric motor and you have your exhaust gases
[01:20] and they're independently controlled. So, how does it work? Well, again, typically those exhaust gases are going to spin up that turbine and then you spool up, you get more boost. Well, now instead of relying purely on those
[01:33] exhaust gases, you have a battery and that battery can send power to the electric motor and that electric motor can spin up your turbocharger without needing any exhaust gases to do it. So you can get to your peak desired boost
[01:46] level without the exhaust. Then once you reach that desired boost level, of a lot of exhaust, that exhaust then takes over. So you only really need this electric portion to help spin it up for a very brief moment of time right at the
[02:01] beginning when you're trying to get to whatever your target torque level is. question, what are the advantages and disadvantages? And it's actually quite a long list of advantages here. I'm going to go through seven. some of them being
[02:14] obvious, some not so obvious. So, first of all, of course, a huge advantage and a big reason for doing this is the fact that you reduce turbo lag. So, the to your torque target. So, if you floor it, you have to wait for that
[02:27] turbocharger to spool up, right? And so, in that scenario, instead of waiting for the exhaust gases to do it, now you have that electric motor and it's a much faster system. You might wonder how much faster? Well, Porsche actually gave some
[02:40] metrics on exactly this. So, in an example, versus the previous Porsche Turbo, which had variable turbine geometry, so a very clever turbo system, geometry, so a very clever turbo system, say you're in fourth gear at 1500 RPM,
[02:53] and you floor it. Now, doing that with the old car versus the new car, the new car with the electric turbos is going to reach that peak torque 2 seconds earlier. 2 seconds. And yes, this is an extreme case because you're at really
[03:06] low RPM. But that is such a huge difference in terms of turbo lag. Of advantage isn't going to be quite as significant because you've already got a to be quicker to get to that peak torque, but there still will be an
[03:21] advantage even at that higher RPM. Okay. The second advantage of an electric turbocharger, you have a wider torque curve, especially that peak portion of It is significantly wider on the new Turbo S versus the previous one. And a
[03:35] big part of that is this electric turbo. And so, why is that? Well, when you think about sizing a turbocharger, if you size a large turbocharger, well, then you get lots of power on the top end, high peak power, but your low end
[03:48] of your torque curve is waiting for that turbocharger to spool up. Contrarily, you could use a small turbocharger, get boost really early, but then it kind of RPM, and you can't get quite as much peak power. So now you just fit a really
[04:02] large turbo relatively speaking and you use the electric motor at low RPM to bring up that torque level. So you have a much wider flat area of the torque curve and you have it across the entire RPM range rather than a more narrow
[04:16] turbo size. And even the previous generation was using a variable turbine geometry which helps widen that torque curve. And even versus that this is such a huge difference in when you have that peak available torque. All right.
[04:30] Advantage number three is anti-lag. So typically with turbochargers there are throttle you can still keep a bit of boost in the system. But here because again you have independent control of the compressor side without relying on
[04:46] the exhaust. You can use the electric motor. You can supply boost in any throttle and then get back onto throttle, you can use the electric portion of the turbocharger, that electric motor, to keep it spinning as
[04:59] get back on throttle, you're immediately back into it. And so, actually, depending on the drive mode that you're in in this vehicle, they target a lower sport plus, they're going to target a
[05:12] that when you do get back onto the gas, it's there immediately rather than, say, turbocharger prepped. It's bringing it up to a slightly higher speed, getting your boost at a higher target level, and then as you get on the gas, boom, it's
[05:26] there much quicker. Advantage number four is energy recuperation. So, we need to kind of understand the entire system here. So, we have a 3.6 L boxer 6-cylinder. Paired between that boxer six-cylinder and the transmission is a
[05:39] traction motor, an electric motor that's applying torque to the wheels. Okay? It's going right into the transmission. Then, of course, the engine has its two electric turbochargers. And then to feed energy to either that traction motor or
[05:51] the electric turbos, you have a high voltage battery. So there's a 400volt voltage battery. So there's a 400volt 1.9 kilowatth lithium ion battery pack. Weighs about 27 kg that can supply energy to either the turbos or that
[06:03] electric motor. All right. So how does energy recuperation come into play? Well, you can use the electric motors in that turbo. They are powered by the exhaust and they can send energy from the turbo acting like a brake that sends
[06:16] that energy either to the traction motor so that you can accelerate or to the battery pack to store that energy for later use. Now, this is a really big advantage and it's a really big part of how this system works because you're
[06:28] almost always using energy recuperation from the turbos except when you're just this is how you're going to set your boost levels. Which brings us into advantage number five. no wastegates. So, we can eliminate wastegates
[06:42] because it differs from some of the manufacturers out there. Like Mercedes has an electric turbocharger application, but in their case, they are still using a wastegate. Here, there is no wastegate. And so, these electric
[06:54] motors can be powered with about 20 kW to spool up or they can recuperate about 14 kW each. And so because they have so much power to recuperate energy to effectively act as a brake on the exhaust and then send that energy either
[07:08] to the motor or the battery. So you can use that to set your boost level. So say for example you had a torque target that needed 10 psi of boost. Well the second you get to 10 psi of boost that turbo is then going to act like a brake on the
[07:22] exhaust and keep the turbo level spinning at a slower speed so that you don't exceed that torque level. And of course, you can use that energy later on as it's gone back to a battery. But this also brings up a really clever advantage
[07:35] number six, more power. And so, how would you have more power using an electric turbo even if the battery was eliminated from the system overall? So, for example, this car has a combined horsepower of about 701. So, between the
[07:50] electric motor and the engine, it can produce a maximum of 701 horsepower. The engine alone is good for about 630 horsepower. But if your battery were always recharging, so you don't really have to think about this, but say you're
[08:04] going for a top speed run and you deplete that battery fully, the engine can still put to the wheels 660 horsepower. So, where does that come from? Well, it comes from that traction motor sitting between the engine and the
[08:19] transmission, and it gets its energy from the electric turbos. So the electric turbos are regenerating about 14 kW each. They're sending that directly to that electric motor. And so instead of your engine power limiting
[08:32] the vehicle's total output to about 630, now you have about 660 horsepower going to the wheels thanks to the electric turbos. How cool is that? So they're effectively raising your peak power, 30 horsepower. But yes, it it is required
[08:47] have somewhere to send that energy. And if you think about what would you What would you typically do at peak power? Well, you'd be using a waste gate to bleed off any excess exhaust gases and just sending all of that energy out
[09:01] the exhaust. So, in this scenario, you're taking that energy and you're redirecting it to an electric motor. So, you're using some of that extra excess energy to help make the car faster. And finally, advantage number seven, which I
[09:14] interested in, but it's still very cool, is that it actually improves emissions by using electric turbos. And I have a couple other videos that explain this in greater detail, but the general gist of it is that using these electric turbos,
[09:28] you can use a larger turbocharger. By using a larger turbocharger at higher RPM, higher loads, that means you have a less restrictive exhaust. Because you have a less restrictive exhaust, you get better combustion, you get lower
[09:43] combustion temperatures, and as a result, that means you can run at a leaner air fuel ratio than you typically would. So this thing can run at a stochometric air fuel ratio at lambda equals 1 in all driving scenarios, all
[09:56] of them. And as a result of that, that is where catalytic converters work at their best efficiency for eliminating everything combined. And so as a result, you get better emissions by using an electric turbo. Now, of course, there
[10:10] being cost. These are going to be more expensive, right? And so this technology, yes, it is going to be an added cost, and yes, there's actually a healthy bump in the price of the new Turbo S versus last year. It's gone from
[10:23] Turbo S versus last year. It's gone from about 230,000 to about 270,000. However, I'm pretty sure the tariffs on imported vehicles from Germany in this imported vehicles from Germany in this exact moment is 25%. And 25% of $230,000
[10:35] would mean this car should be more expensive than it is. So, it's hard to say exactly how much of the price increase is really coming from this new electrified system. And it seems like regardless, they are going to be cutting
[10:48] Disadvantage number two, of course, complexity. Right? We're adding electronic systems to this. We've got the high voltage battery. We've got the two electric turbos. We've got the pancake motor that's sitting between the
[11:01] engine and the transmission. Right? There is a complexity here to it. But there are some things you can eliminate. Right? You can eliminate that wastegate. turbine geometry. Those are very complicated turbos. You've got an
[11:13] electronic actuator for those veins within it. You can also eliminate things like the starter motor, the alternator. This in fact has no accessory belt like the previous engine thanks to using that electric motor in the transmission. So
[11:27] well. It isn't just an increase in complexity. And finally, the big one of course being weight. So each of the turbos including their exhaust manifold weigh about 17 kg. The battery, the high voltage battery weighs 27 kg. The low
[11:44] size. So that only weighs 7 kg now. It you've got the added weight of the electric motor. But combined this only weighs 85 kg more than the previous Turbo S. So you're getting a lot of
[12:00] capability at not a huge weight increase. It actually is pretty capability of this. The numbers it's significantly faster in every way. On significantly faster in every way. On track accelerating, it is 14 seconds
[12:13] faster around the Nervarine. So it is a more capable vehicle in every way. But yes, you do have a bit more weight, but not too big of a hit. 85 kg. So, getting into our final question, is it a good thing? And what does this thing feel
[12:26] like to drive? And it's such an interesting discussion. I was thinking thing that, you know, because it has that electric motor between the engine and transmission, perhaps the turbocharger effect, I'm going to just
[12:39] feel masked by that electric motor, and I won't really know exactly when are these turbochargers spooling up, and they're masked by that electric motor. quite interesting chatting with Porsche engineers about this because the
[12:52] strategy is all of the power from the battery initially is just sent to the that traction motor to help assist with acceleration. And so, let me explain this a little bit. The battery can send out about 40 kW of power. Each of the
[13:08] electric turbos is good for about 20 kW of power. So the full battery capacity is taken up by both electric turbos. So there's nothing left over to send to that traction motor. And what Porsche found out is that in order for
[13:23] increasing acceleration as fast as possible, in order for this thing to be as quick as possible, it was better to send power from the battery to the electric turbos first than to send it to the traction motor first. Yet the
[13:36] acceleration was actually better using that strategy. So in this car when you that you want and then you get on the gas and the initial feeling of acceleration that you get is all coming from the engine, from that boost from
[13:50] the turbochargers being spun up so quickly by the battery. And the strategy with the launch is the same, right? It's really interesting. So, if you put your foot on the brake, foot on the gas, and you release the brake, well, the first
[14:04] thing that's happening is those turbochargers are getting spooled up as quick as possible to max boost, so you get max power from the engine. Then those turbochargers start sending some energy back to the traction motor,
[14:16] right? Because you're setting your limit for those turbochargers with that recuperation from them. So, using them as a break. And so, you're using them as a break, you're sending some of that energy to the traction motor. And if you
[14:28] you can send that to the traction motor. And that's where you get your maximum torque and your maximum power. And so in pretty much any scenario aside from when going to actually be getting recuperation from these turbos. Now, why
[14:44] I say this feels like nothing I've ever driven before is actually a really interesting discussion. So, what happens is typically with a turbocharged car, screen so you get a better idea of what I'm talking about, but if you look at
[14:58] torque or acceleration, the force you're feeling versus time, typically what happens with a turbocharged car is you'll floor it and then you'll immediately get up to about, you know, atmospheric pressure, right? That we've
[15:12] then we've got to wait for the exhaust to build up that extra force. So, you get up to a certain level of torque, then it flat lines for a little while, and then eventually you start to have the boost built back in. Well, here you
[15:25] never really have that flat line. And it's so bizarre because the second you get on the throttle, you immediately get up to naturally aspirated, but then it just kind of it just kind of turns. It doesn't just knock off the torque
[15:38] It just kind of rotates up and you get a steady build of torque until you get to that peak. And so it feels different because a naturally aspirated engine, you just go straight to your torque. Here you just keep having this sensation
[15:52] of torque is always building as you keep your foot down. And it is it's pretty cool. Like preferably, I think still most enthusiasts will prefer like the immediate instant nature of a naturally aspirated engine, but it's a really
[16:07] cool, really unique feeling of never having torque let up. And you don't hit the engine's bogging down. It's waiting to build up that boost. That just to build up that boost. That just doesn't exist with this thing.
[16:20] Wow. And so you just have this cycle where Your boost is building, then you're sending energy to the traction motor, energy to the traction motor. And so all of it just keeps building that torque,
[16:34] and the net result is just a bizarrely quick experience where you just keep building up. So to answer the question, is it a good thing? I would say if it's replacing a turbocharged engine with an electric turbocharged engine, yes, 100%
[16:48] absolutely it's a good thing and it enables greater performance. If it were to be used to replace a large naturally aspirated engine with a smaller turbocharged engine, I would say it's not going to provide that same unique
[17:01] characteristic of a naturally aspirated engine. So it has its advantages in the turbocharger world. in this world where you're seeking maximum performance, right? And a naturally aspirated engine isn't going to be able to deliver this
[17:13] kind of power. But, you know, something like the GT3 RS, it has its own unique character. And that naturally aspirated engine, that punchiness that you get with the throttle is truly a unique and incredible experience. But it is
[17:26] throttle punchiness. I mean, you can see the torque just builds. So, it's a different experience from naturally torque immediately. Here, you get there and and then it just kind of slows, but
[17:40] it keeps building. So, overall, if a turbocharged engine is getting replaced I'm all for it. It is such a cool experience. It's a really unique feel, performance standpoint. If you have any questions or comments, feel free to
[17:56] questions or comments, feel free to leave them below. Thanks for watching.