“and claims a charging rate of up to 11 kW and with an efficiency of about 90% for easy overnight charging.”
That’s a some 9kW lost on a 80kW battery. I get the convenience, but I think the best use for those would be when standardized and installed in public parking spots, for a brief charge bump, not to charge fully at home, e.g overnight, which is what Porsche aims for.
The 90% efficiency of the wireless transmission would be on top of the efficiency of typical charging (which is mostly losses after the power reaches the vehicle).
Do we? Because if you're invoking scare quotes, I don't think you have a good grasp on what's actually happening here.
90% is pretty good efficiency at this level of power. One cannot give an exact figure because it depends heavily on environmental factors, primarily temperature. 90% is pretty much exactly what I'd expect to see in the real world under same conditions.
>One cannot give an exact figure because it depends heavily on environmental factors
Right there. You've restated the problem. "up to 90%" is nothing guaranteed. If the suspension does not lower, you're not getting 90%. If the charger is covered in dirt, you're not getting 90%. If nothing is guaranteed, I'm scared to volunteer.
Well at least doesn’t have to worry about “suspension does not lower” and “charger covered in dirt “ or “cat hides under there for warmth” problems. Those are on top of the existing charging losses.
Heh. I didn't mean it in a gruesome way :-) just saw that someone mentioned it has a sensor to shut it off. So assuming it works as designed a cat might like the nice warm pad to hang out on in the winter. Owner parks hoping to charge their car by morning, the pad charges for 10 min, stray cat notices car is back and hides in there for warmth, charger stop charging immediately, cat moves on, and next day the car is not charged and the owner can't leave for work. It's just not a failure mode a cable has to worry about.
Porsche is famous for underpromising and overdelivering.
For instance they claim a 0-60 time of 2.4s for this car. Car & Driver independently tested it and achieved 2.1s. They also claim 298 miles of EPA range (mixed highway & city driving). Car & Driver worked out 300 miles at a constant 75 mph (which is harder on an EV than city driving.) On the base model, which claims 303 miles range, MotorTrend achieved 350 miles of pure highway driving.
Pick any Porsche and you'll see that they lie to make things sound worse than they really are.
Yeah, the difference between "reported and delivered" in the range of 350-298=62miles is actually that one special thing, that makes Porsches worth the price :-D
German brands in general tend to do that - BMW is notorious for under-reporting power, for example. They'd rather understate than have customers be mad at them for underdelivering.
cromka · · focus · HN ↗
That’s a some 9kW lost on a 80kW battery. I get the convenience, but I think the best use for those would be when standardized and installed in public parking spots, for a brief charge bump, not to charge fully at home, e.g overnight, which is what Porsche aims for.
cisc · · focus · HN ↗
It's about the same as wired AC charging. There are always charging losses:
<a href="https://insideevs.com/features/711659/ev-charger-efficiency-losses/" rel="nofollow">https://insideevs.com/features/711659/ev-charger-efficiency-...
onetwentythree · · focus · HN ↗
cisc · · focus · HN ↗
1970-01-01 · · focus · HN ↗
It is "up to 90%"
We all know what this means in reality.
unrented7977 · · focus · HN ↗
90% is pretty good efficiency at this level of power. One cannot give an exact figure because it depends heavily on environmental factors, primarily temperature. 90% is pretty much exactly what I'd expect to see in the real world under same conditions.
1970-01-01 · · focus · HN ↗
Right there. You've restated the problem. "up to 90%" is nothing guaranteed. If the suspension does not lower, you're not getting 90%. If the charger is covered in dirt, you're not getting 90%. If nothing is guaranteed, I'm scared to volunteer.
blackoil · · focus · HN ↗
rdtsc · · focus · HN ↗
phoronixrly · · focus · HN ↗
drcongo · · focus · HN ↗
DANmode · · focus · HN ↗
If a pet, person, or metal object gets between the pads, the system supposedly stops working so nothing overheats.
So, it might get a cat yelled at ^_^
rdtsc · · focus · HN ↗
crote · · focus · HN ↗
DANmode · · focus · HN ↗
Then you don’t, unfortunately.
> 90% is pretty good efficiency at this level of power
Too good. That’s what they’re saying.
randerson · · focus · HN ↗
For instance they claim a 0-60 time of 2.4s for this car. Car & Driver independently tested it and achieved 2.1s. They also claim 298 miles of EPA range (mixed highway & city driving). Car & Driver worked out 300 miles at a constant 75 mph (which is harder on an EV than city driving.) On the base model, which claims 303 miles range, MotorTrend achieved 350 miles of pure highway driving.
Pick any Porsche and you'll see that they lie to make things sound worse than they really are.
KellyCriterion · · focus · HN ↗
piperswe · · focus · HN ↗