Oils4AsphaultOnly said:
GRA said:
Oils4AsphaultOnly said:
No wonder I can't get through to you. You actually thought your point was made with that C&D article, despite them reporting the Taycan 4S NOT achieving their EPA results using the exact same 2-speed transmission?
I never said there wouldn't be any improvement with a taller gearing (I did mention the lower frictional losses earlier in this thread chain due to a different final drive ratio). I said that whatever gains wouldn't amount to anything significant (I kept referencing 1%). I think you were hoping for 10%? I deleted all your references, because they pointed to a line of reasoning-by-analogy that completely ignores the data. "oh hey, the Taycan has better hwy range than city range, unlike other EV's ... it must be because of the 2-speed transmission!" - although that might be true, the 2-speed transmission would be compensating for inefficiencies ELSEWHERE (just like in an ICE powertrain). Inefficiencies that probably comes from the transmission itself (each rotating gear/mass introduces frictional losses)! In other words, it's not that the hwy rating was so good, it's that the city rating was so bad!
Since you choose to ignore the data, here's a simple question for you. If the Taycan, like all other current BEVs, had a single speed transmission that used one of the two ratios in its two-speed tranny, which would provide better 0-60 times, the low or high gear? Which would provide better efficiency at say 70 mph cruise? A 5% gain, which is what ZF is claiming, would be useful if that translated directly into range. 259 miles combined (2020+ Bolt) becomes 272 miles. Still inadequate for me, but far more useful. For the sake of argument, let's say that the Taycan with a high gear ratio was half as fast 0-60, 5.2 vs. 2.6 sec. Do I care? No, but I do care about the cruising range.
I held off renting a Bolt until the 2020 arrived, because it offered 259 vice 238 miles EPA combined range for the pre-2020s, and given the lack of charging opportunities along my route (along with what I half-expected and what proved to be the unreliability of my being able to initiate a charge) I wanted every bit of range I could get. Another 10-15 miles is better yet, but I want and need at least 300 (preferably a lot more) to be comfortable.
There's no point playing what-ifs with you, because you don't have a fundamental understanding of mechanics. But just for the sake of entertainment:
1) Porsche did the right call in using a 2-speed, because they DID NOT KNOW HOW else to achieve good acceleration and efficient high speed cruising on the autobahn (where speeds of 155+mph are expected from a porsche). The 2-speed was HORRIBLY INEFFICIENT as evidenced by the fact that their city range was LESS than their highway range. You just have to look at how much more energy is needed to push away air at 75mph versus 30mph to realize that city range for an efficient EV should ALWAYS be longer than the hway range. The fact that porsche had a worse city range shows how incredibly inefficient their power-train was! But they had to use it, because their home market has a use case that demanded it.
Do you think that maybe, just maybe, a single-speed EV's city range is better than highway range because they benefit from lots of regen in stop and go driving, unlike in highway cruising? Or do you think that's irrelevant?
Oils4AsphaultOnly said:
2) However, the optimum solution is to drop the 2-speed tranmission (because the extra weight also reduces range) and get an electric motor that had a higher operating range, like the carbon-wrapped motor that Tesla uses. And/or use different gear ratios between the front-motor and rear-motor, because even a 1% improvement is better than none, since you'll have a reduction gear with the extra motor anyway. This is what the former model S uses (back in 2014, the 85d gained 1.5% additional range from this split-reduction-gear arrangement AND stronger regen braking from the additional front motor).
Or, you could build a two-speed transmission that can handle the torque, ans Tesla was unable to do themselves or buy (but Porsche could. I doubt Tesla had the in-house engineering resources, and maybe still doesn't) , and benefit from improved highway range, higher top speed, and AOTBE a quieter cabin at higher speeds.
Oils4AsphaultOnly said:
You have no business judging other people's solutions, because you're misapplying conventional wisdom into non-conventional systems. Wanting 300+ miles of range is fine, but thinking that you know how to achieve that by asking people to reduce the motor power and changing the battery chemistry shows a complete lack of comprehension of the mechanics and factors involved.
Case in point, Tesla's selection of LiFePO4 (a well known LESS energy-dense chemistry) for their new model 3 SR's getting a HIGHER range (not sure about efficiency yet due to additional weight) than their NCA variant shows how you can't just pick things off a macdonalds menu and get a happy meal. Stop judging the work of the engineers, and let their results speak for themselves. You want the longest range EV? That's a Tesla Model S. You want the most efficient EV? That's a Model 3 SR Plus. You want the cheapest, 300+ mile yet efficient EV? That's a Model 3 LR.
The only one ignoring data is you.
Ah, glad you brought up the currently unnamed least expensive Model 3. Since it gets about 10 miles more range than the SR+ but has a 0-60 time that's 1/2 second slower (5.8 vice 5.3 seconds), my guess is that they've increased the size of the LFP pack to match the 3LR's NCA pack, but since it has lower specific energy and energy density than the NCA pack it's heavier than the SR+ and thus reduces the accel. It's also possible that the LFP pack can't produce the necessary power to drive the motor at full power. That certainly would explain the performance changes, as I doubt a gear ratio change would provide that much of a range boost with so little accel reduction. I'm glad someone at Tesla thinks range is more important than accel time for that model, although as it's now $7k more expensive than earlier this year, it's only "least expensiv"e in tesla terms.
Oils4AsphaultOnly said:
GRA said:
Oils4AsphaultOnly said:
We started this thread with you "advising" automakers to reduce the power output of their motors to extend the range that an EV could drive on a fixed charge to 300+ miles. And I told you that you were trying to change physics, because more power comes free with a larger battery, and that simply reducing the power of the motor wasn't going to buy you any significant additional range. You can only get 300+ miles of range with a battery bigger than the 60kwh that's currently being deployed.
Final example to try to get you to understand. The Hyundai Ioniq EV vs. the Tesla Model 3 SR+. The Ioniq's city mpge is 150miles vs. the model 3's rating of only 140miles. Does this prove your point, since the Ioniq has a less powerful motor and doesn't accelerate as quickly as the 3? NO, because the Ioniq is actually 7% lighter than the 3, and city driving range is highly dependent on regen efficiency and vehicle weight! You're barking up the wrong tree with your range vs. power crusade.
Actually, we started this thread by me saying that I valued range over 0-60 times, and that one way to achieve that might be a less powerful motor that was more efficient at cruising speeds, possibly combined with a battery chemistry that was more tilted towards energy than power (for the same volume/weight).
Another way to do that was with a different transmission ratio. But if you don't need power for acceleration, you can use a less powerful and less expensive motor (thus allowing more to be spent on battery capacity for the same price), which is aside from any efficiency advantages that may apply.
Thanks for ignoring the Ioniq (final drive ratio of 7.4:1 for fewer revs) vs. model 3 (final drive ratio of 9:1) example which directly shows a smaller motor AND a taller gear ratio does NOT translate to better efficiency. Sorry, let me correct/clarify this.
IF all else were equal, then YES, a taller gear would improve efficiency (however slight that might be), but as evidenced by the Ioniq, there are more gains to be made in other trade-offs. See the above about your qualifications to judge what are "better" trade-offs.
There now, was
that so hard?
Oils4AsphaultOnly said:
GRA said:
Oils4AsphaultOnly said:
Ha! $500/yr in free electricity is equivalent to $5,000/yr of free H2?!?!
As for the DCFC costs, I think they were over-charged (no pun intended), but that $19M was spent from 2017 til 2020, and is a tiny fraction of the 4,300 fast chargers that were deployed in california. This means MOST of the charging infrastructure was provided by private industry.
No where near equivalent. Hydrogen will not get the economies of scale needed to become viable, because it literally costs too much and thus is too dependent on subsidies.
The largest number of DCFCs deployed in California are probably EA, which is hardly private industry, and many of the rest were subsidized as well; the CHAdeMO Blinks built long before 2017 certainly were. As to future H2 costs, you're entitled to your opinion; companies who are spending billions of their own money to build that infrastructure and the H2 production facilities disagree with you.
Incorrect. Tesla's are the largest number. Although neither are independent entities (as in separate from an automanufacturer), neither are funded by public subsidies
As Tesla is a proprietary standard still only usable by their vehicles, I don't count them. As has been discussed before, they had to build a network themselves because, as Elon said way back when, they "couldn't afford to wait for someone else to."
EA is a different matter, they're non-proprietary and built with funds that would otherwise have been paid to the government as additional fines. The Government has the final say in where and how EA spends the money, it just doesn't pass through the treasury. That is a government-subsidized network. I'm not sure, but while Tesla may have more chargers I think EA now has more stations in California.
Oils4AsphaultOnly said:
Excluding EA and Tesla, EVgo has 300 DCFC sites, and Greenlots has 130 DCFC sites. I don't have the totals for Chargepoint, but it's more than Greenlots. Just from those 3 providers alone (assuming the 293 public subsidies went to them), there's already more privately-funded stations than not. Don't get me wrong, the cost of those fast chargers can not be supported by charging fees alone. The stations needs to be paid for by the manufacturers/shareholders who benefit from the stations and written off as a marketing expense, NOT subsidized with public dollars.
Good, we agree that these are subsidized. Many of the EVgo sites were also subsidized IIRR; don't remember about Greenlots, although there are few of those in state.
Oils4AsphaultOnly said:
As for the companies who are spending "billions of their own money" to build infrastructure ... baloney. There's fewer than 50 operating H2 stations now, and another 100 coming soon (most of them relying on public subsidies that amounted to over $300M), I can only see less than $500 million (both private and public) being spent on this paltry infrastructure, and most of that coming from the taxpayers, NOT industry.
See what's happening overseas. H2 infrastructure and production is getting lots of private funding.
Still catching up, so will reply to other posts tomorrow.
