“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.
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.