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GM has also been mentioned working with Witricity in the past.
http://witricity.com/witricity-working-gm-test-wireless-ev-charging-system/

I frankly find the "70% of PHEV owners don't plug in" stat hard to believe....unless they only surveyed Toyota PiP owners.
It does address that in the article. Sounds like they are just talking about PHEV drivers-

“About 70 percent of plug-in [hybrid] customers never bother to plug in,” Gruzen says. “They don’t want to deal with cables. And broad, mainstream consumer behavior does not change, as it might with the 1 percent who are early adopters. I plug in every day—I’m a career-long tech early adopter—and let me tell you, it’s a pain in the ass.”

So wireless charging for EVs isn’t just a trick; it’s a marketing necessity. And for it to catch on, it’ll have to be affordable.
I don't get his PITA statement though. I think it's pretty easy. I don't know about marketing necessity either, but there are some seriously lazy people out there. I personally won't bother with it because I'm too cheap to pay for that rig, I don't want to waste anymore electricity than I have to and that's not as efficient as plugging in and I don't want that pad thing on my garage floor because I use my garage for all kinds of things besides just car storage.
 

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Discussion Starter · #4 ·
...I don't want that pad thing on my garage floor because I use my garage for all kinds of things besides just car storage.
Would finally get me motivated to move the oil pan that I still park over even though it's not needed anymore.

If price point is truly around $800. Noticed the article was missing wattage at that price point.

Also: https://cleantechnica.com/2018/01/28/wireless-charging-myths-exploded-witricity-ceo/
No charging method is 100% efficient. Conventional chargers are typically 88% to 95% efficient. Wireless charging is right in the middle of that range at 90% to 93%
Googling different systems I've seen as low as 3.4 kW to as high as 11 kW.

Wonder how hard it would be to retrofit the receiver into the Bolt.
 

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Would finally get me motivated to move the oil pan that I still park over even though it's not needed anymore.

If price point is truly around $800. Noticed the article was missing wattage at that price point.

Also: https://cleantechnica.com/2018/01/28/wireless-charging-myths-exploded-witricity-ceo/


Googling different systems I've seen as low as 3.4 kW to as high as 11 kW.

Wonder how hard it would be to retrofit the receiver into the Bolt.
Gotta be careful about how they word things. Sales folks are sneaky. The text in the article says: Gruzen says that in early, low-volume production the cost difference between the wireless system and the conventional plugged-in one could be in the US $800 range. So if they're assuming that regular equipment costs $1200, then the wireless system will cost $2000.

I still want it. For my Gen2 Bolt :)
 

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Discussion Starter · #6 ·
Gotta be careful about how they word things. Sales folks are sneaky. The text in the article says: Gruzen says that in early, low-volume production the cost difference between the wireless system and the conventional plugged-in one could be in the US $800 range. So if they're assuming that regular equipment costs $1200, then the wireless system will cost $2000.

I still want it. For my Gen2 Bolt :)
Thanks for the clarification. That was pretty sneaky. Totally missed that on the first read.
 

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I don't understand the appeal. If you timed me, I might be under 5 seconds to grab the EVSE, pop the cover, and plug in. I'd trade 10 seconds of my life every charge to not waste the 10-20% electricity that wireless charging throws away as heat.

I'm OK with my toothbrush wasting minuscule amounts of energy wireless charging, but not when we're talking kWh.
 

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I don't understand the appeal. If you timed me, I might be under 5 seconds to grab the EVSE, pop the cover, and plug in. I'd trade 10 seconds of my life every charge to not waste the 10-20% electricity that wireless charging throws away as heat.

I'm OK with my toothbrush wasting minuscule amounts of energy wireless charging, but not when we're talking kWh.
Um, your plug in charger currently wastes ~10%. The wireless charger would waste ~10%. So what's the beef?

It'll be interesting to see how this works out in the wild, but seeing as they are at least willing to share some details, I am more inclined to accept it: http://witricity.com/wp-content/uploads/2016/12/White_Paper_20161218.pdf
 

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Um, your plug in charger currently wastes ~10%. The wireless charger would waste ~10%. So what's the beef?
No, the plug in EVSE does not waste 10%. The majority of those losses occur as a result of cooling systems on the car being active, losses in the chemical conversion process within the battery, and other charge circuitry loads that are active when charging. The 10-20% loss with wireless charging is in addition to the original 10% loss, making wireless charging something like 70% efficient "from the wall".

Assuming 12,000 annual miles, and 4 miles per kWh, a 20% loss would mean an extra 600 kWh needed every year to charge the vehicle. At my utility rates, that's less than $60, but I still don't want to pay more for a charging platform that is significantly less efficient than the extremely easy system of plugging in.
 

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I don't get his PITA statement though. I think it's pretty easy.
I agree it's pretty easy to plug in and unplug in at home.
I do understand his PITA statement tho.
Not for me (or probably anyone who honestly has done it a bit), but...
It's an article on a site that sells (or wants to) wireless EVSEs. ;-)

desiv
 

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No, the plug in EVSE does not waste 10%. The majority of those losses occur as a result of cooling systems on the car being active, losses in the chemical conversion process within the battery, and other charge circuitry loads that are active when charging. The 10-20% loss with wireless charging is in addition to the original 10% loss, making wireless charging something like 70% efficient "from the wall".

Assuming 12,000 annual miles, and 4 miles per kWh, a 20% loss would mean an extra 600 kWh needed every year to charge the vehicle. At my utility rates, that's less than $60, but I still don't want to pay more for a charging platform that is significantly less efficient than the extremely easy system of plugging in.
Did you read the entire article - particularly the "Myth #1 " section? For reference, they are measuring efficiency between the wall and battery. The act of taking 240v AC and rectifying it to 400v DC results in losses of about 10%. WiTricity's wireless charging using the resonance method described by the article also results in ~10% losses. This is not the same technology used in phone or toothbrush charging which uses inductive coils. BTW, they're only talking about the charging losses, not the conditioning loses which should be the same/similar on either system if the charge rate is the same.

If you have data that compares the efficiency of a WiTricity based charger to a wired charger, please share it.

From my layman's read, it seems they're sorta doing for electrical transmission what lasers do for light - focusing the transmission. If Hyundai (or whoever) is prepared to equip their cars with it I hope it's more than a stunt.

I suspect the initial target will be commercial, not residential. Eventually, if enough brands support this, then it won't matter if you have a Tesla, Chevy, Nissan, etc, just pull up over the pad and charge - the connector becomes moot.
 

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Did you read the entire article - particularly the "Myth #1 " section? For reference, they are measuring efficiency between the wall and battery...

If you have data that compares the efficiency of a WiTricity based charger to a wired charger, please share it.

From my layman's read, it seems they're sorta doing for electrical transmission what lasers do for light - focusing the transmission. If Hyundai (or whoever) is prepared to equip their cars with it I hope it's more than a stunt.
I hadn't read the article when I first commented. There are so many breakthrough stories that never result in anything that I get desensitized to them.

I'm not up on the physics, but oscillating energy in a coil of wire cannot be more efficient than directly conducting energy in a wire. However, if it can approach the same efficiency, then the convenience will outweigh the relatively minor loss.

If the claims are true, then this is the most under-hyped technology out there. Count me as skeptical, but hoping to be wrong.
 

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Um, your plug in charger currently wastes ~10%. The wireless charger would waste ~10%. So what's the beef?
I cannot imagine this is true. Somewhere A/C from the grid has to be converted to D/C for your battery. Plus the D/C has to be stored into the battery. This is what the vast majority of the losses in normal (wired) charging systems are associated with. IMHO, these losses cannot be avoided, simply by switching to wireless charging. Losses resulting from the wireless transportation of power itself are added on top of these. In other words, how can a wireless charging system ever be as effective as a wired system?
 

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I cannot imagine this is true. Somewhere A/C from the grid has to be converted to D/C for your battery. Plus the D/C has to be stored into the battery. This is what the vast majority of the losses in normal (wired) charging systems are associated with. IMHO, these losses cannot be avoided, simply by switching to wireless charging. Losses resulting from the wireless transportation of power itself are added on top of these. In other words, how can a wireless charging system ever be as effective as a wired system?
All else being equal, I'll sum it up in two words....

...it can't.
 

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I cannot imagine this is true. Somewhere A/C from the grid has to be converted to D/C for your battery. Plus the D/C has to be stored into the battery. This is what the vast majority of the losses in normal (wired) charging systems are associated with. IMHO, these losses cannot be avoided, simply by switching to wireless charging. Losses resulting from the wireless transportation of power itself are added on top of these. In other words, how can a wireless charging system ever be as effective as a wired system?
All else being equal, I'll sum it up in two words....

...it can't.
This sounds like skepticism for skepticisms sake, or a classic "argument from incredulity" fallacy. Unless, of course, you have data that can refute the existing data that we currently have.

It may turn out that to get the efficiencies mentioned you requires having the pads in such precise alignment that it's impractical. But that's all supposition. For example: CPU's should have been limited to about 65nm due to diffraction of the laser used in etching, but Intel are building at 14nm. It's not magic, just a clever application of good science.

Since a manufacturer (Hyundai?) is apparently getting on board with this, I'll give them the benefit of the doubt until I see data to the contrary. I hope it works.
 

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It may turn out that to get the efficiencies mentioned you requires having the pads in such precise alignment that it's impractical.
That's not a "may turn out", that's a given. Perhaps you can get reliably good efficiency with some sort of system that automatically aligns the pads, but I remain skeptical.

Theory and marketing department claims don't sway me, much less claims on an Internet forum. But an actual working real-world product with better than 95% efficiency would.
 

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This sounds like skepticism for skepticisms sake, or a classic "argument from incredulity" fallacy. Unless, of course, you have data that can refute the existing data that we currently have.
What data would that be? From the article you refer to:

A common question about wireless charging is: How efficient is it? The end-to-end efficiency of a
wireless energy transfer system is the product of the wireless efficiency (see Physics of Highly
Resonant Power Transfer for an explanation) and the efficiency of the electronics (RF amplifier,
rectifier and any other power conversion stages, if needed). In high power applications, such as the
charging of electric vehicles at multi kilowatt levels, end-to-end efficiencies (AC input to DC output)
greater than 94% have been demonstrated. Such efficiencies require that each stage in the system
have an efficiency at 98-99% or greater. Careful design in each stage is required to minimize losses
to achieve such performance.
So, 94% efficiency from AC input to DC output is achievable. That is very nice. But each of the components involved must be 98 - 99% efficient to achieve this. The only component from a wireless setup that also appears in a wired setup is the AC/DC converter. IMHO, when this component is 98 - 99% efficient, the overall wired setup would also be 98 - 99% efficient, as there are no other losses. So, 4 to 5% more efficient than a wireless setup.

It appears that the 94% efficiency reported here does not include losses associated with actually storing the energy into the battery. IMHO, when we talk about charging efficiency, these kind of losses are typically included.
 

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What data would that be? From the article you refer to...
That's why I'm skeptical. The only evidence of those efficiency levels come from their own marketing "myths debunked" page. I've not seen any other research to validate those claims, and to the contrary, find much more evidence that resonant inductive power transfer is less efficient than non-resonant inductive power transfer, with the only advantage being a greater transmission distance.

I'd be happy to be wrong about my assumptions, but I'm just not seeing the evidence so far.
 
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