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Brian P
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Reality 1: The internal combustion engine is still going to be with us for a looong time. At this point a 1% improvement in gasoline engine fuel consumption saves more petroleum than the entire market share of EVs does if you completely neglect whatever it takes to generate the electricity that they are using. Reality 2: Buyers will have the choice between a Cruze (diesel or gasoline) with this transmission or a Bolt. in the same dealer. THEY will decide. And that is as it should be. Second and third ratios look awkwardly close together.
... or a device to game the Japanese emissions and fuel economy testing procedures, and probably Euro NEDC while they are at it.
Actually, this powertrain has NO plug-in at all. It is a hybrid vehicle ... not a plug-in hybrid. And let's not be legislating or prohibiting specific technologies, please. Let them survive or wither out on their own merits. Maybe Nissan has figured something out that Toyota and Ford have not. If they have ... more power to them and I wish them success. If reality intervenes ... let the consequences flow forth; they will become apparent in due course. Series hybrid has not historically been the optimal way to set up a powertrain - but there are specific circumstances where it could be. Those circumstances don't coincide with my own driving patterns (lots of suburban and motorway). That doesn't mean they won't coincide with someone else's (heavy stop and go).
They weren't and aren't free. An engine with VVT costs more to manufacture than one without. It has parts that don't exist in a non-VVT version of the same engine, and those weren't made for free. It's low cost ... not free. It might be "no extra cost" as in, not a line-item option that you have to pay for when placing an order for the car, but that doesn't mean it was free ... it just means you don't have the option of not paying for it.
Series hybrid traditionally isn't very efficient in straight motorway conditions because of the energy-conversion losses (mechanical to AC electric to DC to chemistry inside the battery, then chemistry in the battery to DC to AC and back to mechanical in the traction motor). If the engine output more-or-less matches demand then you can avoid at least some of the battery charge/discharge loss, but the others are still there. Whether all these losses balance the ability to stop the engine under more circumstances and only allow it to run under more efficient operating conditions ... is a crapshoot and will vary depending on circumstances. All this is why a Prius operates with mostly mechanical drive from the engine at higher road speeds. And so does a Volt, and so do all the other hybrids. There's a reason they did it that way. The Japanese test procedure is hopelessly optimistic. Circumstances that contain a lot of idling and very gentle acceleration and low speeds could very well offset all those energy-conversion losses by keeping the engine stopped more. But take the same vehicle out in the real world of higher speeds and faster accelerations and (for most of us) less idling ... and it is likely to be less efficient under those conditions than even a conventional non-hybrid powertrain. I await the real world testing ... ! ! !
Cam phasers aren't "no" cost, but they are fairly low cost. Most recently designed spark ignition engines have cam phasers on the intake camshaft at a mininum and many have it on both, and it's a common strategy to use them to emulate the Atkinson cycle when operating at part load. They switch to more normal cam timing events when acceleration is demanded.
The 48V systems are really just meant for auxiliary systems like HVAC (air conditioning compressor), fast-acting starter motors for stop/start, and mild e-assist systems. If you're going to the trouble of putting an electric motor/generator in place of the torque converter inside a transmission, you are better off making that part of a "Real" hybrid system, something with enough power to drive down the road. In that situation, it's better to operate it at a higher voltage in order to get the current down (and reduce the size and mass of all copper conductors in the system).
Ships have very long service lives (25 - 30 years). Using low sulfur fuel is something that can be done that benefits emissions from not only new ships but also existing ships. Using LNG, or alternative powertrains in general, is something that is only viable on a new ship, since it has to be engineered in, not added on, and then it takes a long time for the fleet to be renewed. As for the post above ... Let's see the cost estimate to cross the Pacific ocean ... someone needs to do some math for us. Realistic numbers, please, not just hopelessly optimistic randomness. And you want to have just one connection? Not much redundancy there. One ship that goes down is a tragic loss, but nothing compared to what would happen if that single connection went down - or if something happened at the terminal at either end. It would sure be a target for the terrorists out there. A ship can sail from any port that it can fit into, to any other port in the world that it can fit into. Same with airplanes. Can't do that with fixed links. Travel with any such system would require a whole lot of stopovers and transfers - just like taking the bus or train, but waaaaaay worse if expanded to a global scale. How does that proposed Hyperloop deal with crossing tectonic plate boundaries (earthquake zones)? I genuinely don't know the answer to this. A connection between Australia and Asia would have to gradually become shorter over time ... and it would have to cross a pretty active geological zone which also happens to be an ecologically sensitive zone. For that matter, much of the west coast of North America is either geologically active or ecologically sensitive or both. Major construction projects on land in a lot of British Columbia are hard to get done.
A number of the latest transmission designs already allow for a clutch and electric motor/generator to be installed in place of the torque converter (the clutch is needed to allow the engine to be stopped). The ZF 8-speed (longitudinal) and 9-speed (transverse) transmissions are like this, and there are a few production vehicles that make use of it (and more are coming). Hyundai and VW hybrids also use this layout.
I should also add that with regards to the "million miles per fatality" statistics, when you get towards the vehicles that have big numbers, it's because they have a small number of fatalities. This, of course is a good thing, but it also means that the sample size (of fatalities) is small, and random situations that lead to just one more or one fewer fatality can shuffle the order with no real underlying reason behind it. The Accord and Impala numbers should have good statistical significance, but the others could be in any order depending on random circumstances. "Million miles per fatality" is also strongly affected by demographics. Two vehicles with identical collision performance, but one of them is bought by teenagers and another by fortysomethings, will have drastically different real world crash frequency. There were a number of minivans a couple vehicle generations ago which had notoriously poor offset-frontal crash performance, but yet few real-world fatalities, because of who drives them and how. I'm not concerned with Tesla's collision safety.
Autopilot is not "approved by all authorities jurisdiction by jurisdiction before it is deployed feature by feature just like the autopilots of other car makers". That ain't the way it works (for now). In North America, there is no third-party approval body for ANY such thing. The auto manufacturers self-declare compliance with FMVSS (USA) or CMVSS (Canada); NHTSA or Transport Canada review submitted paperwork, do occasional spot-checks, and investigate complaints. That's it. Some other jurisdictions (notably EU) do have a third-party type-approval process, but the approval bodies have a set of rules that they follow and check compliance with, and if it conforms to the standard then they grant WVTA (whole vehicle type approval). There currently IS NO standard that governing bodies apply to driver-assistance systems, never-mind self-driving systems! If there is no standard then the type-approval body has no grounds to say "Nein"! Those falcon-wing doors have been troublesome, and it doesn't take a whole lot of searching to dig up all manner of issues with them. Check Consumer Reports, if nothing else. Oh look; they are skeptical of Autopilot, and the Model X is not recommended due to the falcon-wing doors:
If Tesla is so far ahead of the rest of the players as a certain other person thinks they are then they'll be the ones to find out the hard way. FMEA. MTTFd. They mean something. I'm not convinced Elon Musk knows or pays heed. Everyone else who designs stuff for the auto industry has nightmares about those. Ignoring them doesn't make them go away. It just ensures that you'll get bitten by them. And just for the record, I'm not anti-Tesla. A customer of mine builds parts for them. I love a lot of the things they've done ... but not Autopilot, and not falcon-wing doors, both of which I consider to be FMEA failures!
I am not talking about liability for individual collisions. I am talking about general product liability as a whole - the responsibility of a manufacturer to sell a vehicle which is, to the extent reasonably foreseeable and within the limits of available technology, free of safety defects. This is not just "oops, I bumped into the other car". This is GM ignition switches plus Toyota "sudden acceleration" plus Takata airbag explosions magnified by hundreds, if not thousands, in terms of potential liability if there is ANY fault found in the software. Tesla's "autopilot" system DID prompt a lot of discussion in engineering circles about the safety of these systems and their relative failure to account for human psychology. There is a fair argument that the de-activation of (seemingly all?) autopilot features with the introduction of the new hardware is a tacit admission by Tesla that the system should not have been implemented and marketed in the way that it was. It should have been implemented and marketed as adaptive cruise control and lane-keeping assistance ... just as other manufacturers have done. Calling it "autopilot" led to misinterpretation that the system had more capability than it actually did. Obviously this new version has much more capability ... I'm just waiting for someone to see what it will do in a snowstorm.
Deploying such systems prematurely, before the technology is ready for prime time (and it isn't), would be "mass murder". It will eventually happen but it will take a lot longer than Henrik predicts it will. Liability is one thing Henrik has not considered. When an individual driver causes a collision the liability repercussions are pretty limited to that driver's insurance coverage. When a big faceless corporation does something that causes an injury, the lawyers get dollar signs filling their eyes.
Just to be clear, I'm not opposed to the idea, I think it has its applications, I just have no interest right now to have or use such a vehicle myself. Maybe when I'm 90 years old (that's one of the applications). Elements of this technology have a use in preventing people from getting in trouble (e.g. preventing someone from driving through a red light or stop sign with other traffic coming, or preventing someone from making a left turn in front of another driver). I think the average person is a lot more opposed to the use of public transit than the optimists think they are. Car-sharing is likely to get people OUT of public transit and it won't help reduce congestion. And for all those idealists who think everything in the future is going to be automated ... I'd like to know whether those people think their own jobs are going to be automated. I know that automation in the world of manufacturing has replaced drudgery (an army of people each holding a manual spot-weld gun and pushing a button a thousand times per shift) with other jobs requiring skill - someone has to design the tooling, program the robot, and fix it when it breaks (and I'm one of those people). And someone still has to handle the parts that are going into the automation equipment ... It isn't practical to automate everything, and what would people do for a living if we did?
Airplane pilots have the ability to "think out of the box" when something goes wrong. They have the ability to judge whether a situation warrants emergency actions or can safely be ignored. They can manually pop the circuit breaker on a faulty electrical circuit. They can judge whether they can safely land with one of the landing gears not fully engaged. A fully automated aircraft without such an experienced pilot on board ... crashes.
It's one thing to handle a stop sign and a traffic light automatically at an intersection with all sorts of nice visible lane markings. It's quite another to handle it when all the markings are covered in snow. Or glare ice. Or the intersection is under construction and there aren't any markings. Or the power is out and a police officer is directing traffic. Or (as happened in a major blackout in Toronto in 2003) everyday citizens were directing traffic because there weren't enough police officers to cover all the intersections and they had enough other headaches on their hands. And even if it's sophisticated enough to handle that (which I doubt) ... How does the software distinguish a citizen directing traffic in the midst of a blackout ... from a teenager playing havoc, which you know is going to happen! I have little doubt that Tesla will be able to produce a better "autopilot" that works in more circumstances and that those circumstances will constantly increase in scope over time, but they are a loooooong way from being able to be summoned autonomously in the midst of a power blackout due to a snowstorm.
Show me the BSFC map. Operating the engine just above idle but under heavy boost is a recipe for having to implement a lot of detonation-control measures (EcoBoost is direct-injection but that doesn't exempt it from detonation) and those all cost efficiency. The turbo won't be in an efficient operating range that low in the revs, so the boost pressure will be coming from this gizmo (eating up crankshaft power), and "underexpanding" the power stroke isn't a recipe for making efficient power. Again ... show me the BSFC map. A three-banger running at 1200 rpm near full load (boosted) is apt to be mighty rough, too.
... and your point is? Do you want to go back to the old low-performance sealed-beam round headlights? Think about aerodynamics for a moment ...
I know the "idea" is to downsize for less friction and lower pumping losses ... and it works for getting through the very light engine loads in the European NEDC or most of the US EPA emission and fuel consumption testing. But it doesn't work in real world driving. The discrepancy between official and real world fuel consumption figures is increasing, and something like this would only increase it further. 32 mpg US = 7.3 L/100 km; this isn't particularly remarkable. Lots of cars with 200ish hp from larger displacement normally aspirated engines (and the usual variable valve timing that is used nowadays) will do that on the highway. Among rental cars, I had an Impala (2.5L normally aspirated 4 cyl) do better than a Cruze (1.4L turbocharged 4 cyl).
The article is silent on what the BSFC is when the engine is running under boost. 184 lb.ft torque from a 1.0 L engine means it is running at a very high boost pressure (probably somewhere near 2 bar boost = 3 bar intake manifold pressure) in order to achieve that. Real world experience with highly boosted gasoline engines has been that they can be economical when puttering around at light load (typical of government emissions and fuel consumption testing) but thirsty when put under load. This approach is essentially the opposite of the Atkinson cycle (which uses a higher expansion ratio than the compression ratio). Mechanical supercharging pretty much translates to a higher compression ratio and then throwing half of the power stroke away.
Now we just need NHTSA to get out of the stone age and allow this technology in the USA!
Resistive heating elements can be put right in the item to be heated (e.g. seats, steering wheel), the intent being that you no longer have to heat the air (as much). It isn't feasible to do that with a heat pump. Heat directly applied to the windshield (via a resistive film) to defrost or defog it or melt snow/ice on the wiper blades is both more efficient and more effective than blowing air at it. This isn't an application for this plastic film but it's an example of where resistive heating will work and a heat pump is not feasible or not as effective, or both.
Henrik, VW optimistically wants 25% of their sales to be EV somewhere in that timeframe; EVs thus far have not met sales expectations. You really think they should stop development on everything that accounts for 75% (likely more) of their sales?? At this point in time, reducing consumption by 10% in the combustion-engine fleet is a more constructive exercise than leaving that technology to wither and (hopefully) replacing 10% of the sales with EVs. (Those EVs still require energy to be recharged ... and some of that energy to recharge them is coming from fossil fuels ... even more of it, if Germany doesn't operate their nuclear plants!) And, plenty of human-driven vehicles will still be sold after 2025 (which is only 8 model years away). I want no part of autonomous driving. I'll tolerate it as an option as long as it can be switched off (or not bought). In any case, the problems with getting vehicles to operate autonomously and without errors in all weather and traffic conditions have been underestimated. Tesla's "autopilot" system should have never been marketed as such; it is nowhere close to being an autonomous system and the real world evidence of that is mounting ... I'd be surprised if VW figures this out by 2025. I like this vehicle, though. A lot of the more radical features of it won't make production, though. (It's going to have tires with actual sidewalls, it's going to have a B pillar, the back doors will open the normal way, etc.)