GCC: ORNL demonstrates 120 kW wireless charging for vehicles; 97% efficiency

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GRA

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https://www.greencarcongress.com/2018/10/20181020-ornl.html

. . . In the laboratory demonstration, power was transferred across a six-inch air gap between two magnetic coils and charged a battery pack. . . .

The demonstration advances DOE’s extreme fast-charging goal to develop a system that delivers 350 to 400 kilowatts and reduces the charging time for electric vehicles to 15 minutes or less.

ORNL researchers will explore innovations to increase power transfer level to 200 and eventually 350 kilowatts, while refining dynamic wireless charging technology.

A dynamic system enables the automatic charging of electric vehicles using wireless charging pads installed under roadways; higher power charging systems are needed to minimize the cost and complexity of dynamic charging. The goal is dynamic charging at highway speeds, Galigekere said.

The research was funded by DOE’s Vehicle Technologies Office (VTO) and performed at the National Transportation Research Center, a DOE user facility at ORNL.
While high power may be needed to minimize the cost of dynamic charging, I fail to see how high power dynamic wireless charging can minimize the cost and complexity relative to static wireless charging, as to fully charge you'd need 15-20 miles of charging lane, with the attendant transmission and efficiency losses.
 
GRA said:
While high power may be needed to minimize the cost of dynamic charging, I fail to see how high power dynamic wireless charging can minimize the cost and complexity relative to static wireless charging, as to fully charge you'd need 15-20 miles of charging lane, with the attendant transmission and efficiency losses.

Hmm... Might be only 50% efficient or so.

With a few hundred such "charging lanes", you could drive coast to coast without stopping... other than for biological reasons.

Can hydrogen top that?
 
WetEV said:
GRA said:
While high power may be needed to minimize the cost of dynamic charging, I fail to see how high power dynamic wireless charging can minimize the cost and complexity relative to static wireless charging, as to fully charge you'd need 15-20 miles of charging lane, with the attendant transmission and efficiency losses.
Hmm... Might be only 50% efficient or so.

With a few hundred such "charging lanes", you could drive coast to coast without stopping... other than for biological reasons.

Can hydrogen top that?
Doesn't need to. Either approach would probably be an adequate replacement for ICE capability. I've got to wonder what the cost of such a wireless charging system would be, given the need for much more frequent repaving of freeways (compared to parking spaces) owing to the beating they take from loaded semis tooling along at speed, and any time you had to do maintenance on the wires in between repaving, you'd have to close the lane.

I'd love to see some detailed cost projections for such a system that covered all the freeways in the country - 47k miles of interstate plus the U.S./state freeways. The ones I've seen tend to be back of the envelope calcs by non-experts like this one:
Are car-charging roads the future? Probably not
The wireless tech works, but it's too expensive.
https://www.mnn.com/green-tech/transportation/blogs/are-carcharging-roads-future-probably-not

or else pie-in-the-sky predictions by companies developing the tech. The critical issue would be whether it would allow much smaller battery packs on board, thus saving in overall system costs. But batteries are also getting cheaper, and that would have to be weighed against the cost/availability of copper. Here's a more recent article that falls somewhere in between the extremes:
Israel Tests Wireless Charging Roads for Electric Vehicles
New technology could power buses and cars on the go, but will it be cost-effective?
https://www.scientificamerican.com/...ireless-charging-roads-for-electric-vehicles/

So, by all means keep doing R&D and some demo test strips like Israel is doing.
 
An article from GCR reporting the same info, but with more details:
Wireless charging could widen efficiency edge over cords, suggests DOE lab
https://www.greencarreports.com/new...n-efficiency-edge-over-cords-suggests-doe-lab

Researchers at the Department of Energy’s Oak Ridge National Laboratory last week announced they've managed to transfer 120 kw of power at an efficiency of 97 percent—more efficiently than any currently available physical charging connection. . . .

Today’s DC fast chargers have reached about 94 percent efficiency, but as we reported earlier this week, a new design claims a 97.6-percent efficiency at full power.

In either case, it would be a lot more efficient than Level 1 charging from a 120-volt household AC socket or Level 2 charging via a commercial or home charging station running on 240-volt AC. Those systems, in a best-case scenario, according to the charging-hardware maker ABB, have about an 88-percent or 93-percent efficiency, respectively, at best. And that’s not counting losses at the pack, which may total another 5 to 8 percent according to some studies.

While wireless charging for vehicles is certainly not a new idea, the power levels are. The SAE established J2954, a specification guideline for wireless charging up to 7.7 kw, aimed at light-duty vehicles and operating in a common frequency band (85 kilohertz), in May 2016. Based on tests conducted by another DOE lab, Idaho National Laboratory, it was verified that at up to those power levels even unmatched hardware could achieve a 93-percent efficiency. . . .

The barrier even for static wireless charging continues to be cost, however—an estimated $1,500 to $2,500 per vehicle, according to Navigant—for a benefit that automakers haven’t been able to justify yet. If researchers and companies can make higher power levels and cross-compatibility work (at efficiency advantages), then the barriers might quickly dissolve.
 
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