I believe these folks know a bit about thermodynamics....
Oak Ridge National Laboratory demonstrates 100-kW wireless charging with a 'polyphase' coil system, unlocking a potential 350 miles per hour of charging.
www.autoblog.com
From your link:
Earlier this month, after parking a
Hyundai Kona EV over a new wireless
charger design, the scientists and engineers registered a max wireless charging rate of 100 kW across a
five-inch air gap at a claimed efficiency of 96%
You'll note I said a foot of freespace (12 inches) in my original comment based on my assumption for the vehicle we were talking about in this thread, the Cybertruck. Now that I check it actually has a clearance of 17.4 inches.
I will admit 96% at 5 inches is better than I expected, but remember your inverse square law still applies even if this is electro-magnetic coupling and not radio wave transmission.
So let's be generous and assume they lost 1% efficiency on each set of coils (and that is likely exceptionally generous), that would mean 2% loss of power at 5 inches. At 10 inches you would have 4 times the loss or 8%, which already puts you at 90% total loss under these laboratory conditions. 12 inches would be closer to 83% total loss. At 17.4 Inches (more than 3 times the measured distance) you would lose more than 16 times as much power, 32% in our example from the article.
So my original claim of 90% at a foot is almost certainly correct, thank you for providing the proof to back it up.
So does that mean this tech is unlikely to work? Not at all, it just means there is likely to be an active component (a platform that raises until it gets within 5 inches of the receive coil for instance) rather than just a flat parking space.
electrek.co
