I think you could work around that using a static field in the road. Since the vehicle is moving the change in field is taken care of by this and you would end up with a pulsed charging system. Efficiency would probably be dictated by the vehicle speed and coil layout (with the biggest issue being coil distance for field coupling).
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I’m pretty sure the physics don’t work for that. It would take energy to push the car forward through the alternating magnetic field to induce current in the charging coil on the vehicle. Otherwise we could all just harvest free energy from permanent magnets.
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It’s a nice idea, but inductive charging is really, really inefficient. I doubt it will ever see practical use for charging cars. Press releases like the OP are nice and all, but the physics on inductively charging cars from the roads just doesn’t work.
Inductive charging incurs enormous losses over distance by the inverse square law. Even a few millimetres kills it. This is why your phone’s charge coil has to be right up against the back, and even then it gets very warm and charges very slowly.
Electric cars need literally kilowatts of power transfer. Induction coils that could do that would be larger than the car and melt everything in the vicinity, and even then would hardly charge fast enough to be worth it. You’re way better off with high efficiency solar panels on the roof, trunk, and hood to extend range a bit. They aren’t practical yet either, but they’re improving all the time and getting pretty close to where they might be worth doing.
Pantographs would be practical, if you could somehow get all the car makers to agree on a standard for that.
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Depends on what’s fueling the production of the electricity.
It’s not quite that bad, depending on the size and design of the coils. There are commercial devices already in service to recharge (parked) electric buses that are rated over 100 kW and operate with an air gap of 5" or so. But like I said upthread, I’d be very curious to know what the efficiency would look like for moving vehicles.
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Wait, what if we put power back through the coil in the car and then it could act like a mag lev train (not the floaty part, but the propulsion)… 
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I’m not suggesting that embedding a continuous inductive charging system in roadways will replace all of the regular chargers, but as a range-extender this technology has a future. It doesn’t need to be efficient to be useful.
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Screw that, I want the floaty part!
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Oh! So we could get free unlimited energy from this as well? Alright! Sounds great. When can we start? 
That does take care of the aforementioned snow removal issue.
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Too many socket types / no standardisation. Otherwise they’d work fine. 
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That’s not remotely true.
First, what do you mean by “not produced by 100% renewable sources?” Is 99% green still worse for the environment than gas? 98%? 85%? Do you have a specific number for when it switches to being worse, or are you really suggesting 100% or nothing?
It’s also just not true. Even powered by “dirty” grids, the efficiency of dirty energy produced by the grid, even including transmission losses, is still generally better than the efficiency of an ICE. And they have the further advantage that they get cleaner as the grid gets cleaner, as almost all electrical generation on the planet is doing.
High emissions from dirty grids remains a persistent EV myth, in part due to outdated information on the power-generation mix, but it’s largely been debunked by research. A study last year found that EVs are already cleaner than gasoline cars in 95% of the world.
Even when factoring in emissions from battery manufacturing and materials sourcing, a recent Reuters analysis found that electric cars have less environmental impact than gasoline cars after a short time on the road.
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Is this the solution? Nope.
But they gotta start somewhere and failure is how they get to the solution.
Well that didn’t work but we did learn some things.
I just had a silly conversation with a neighbor about this, he’s 70 and really worried they are going to take away his pickup truck. That’s never happening in his lifetime or mine, maybe my daughter’s and probably my grandkids will see 100% EV.
Once all the dinosaurs like my neighbor die off and the kids grow up and don’t have any push back things will happen but I’ll never see it.
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No, but it needs to be practical. If it’s hugely inefficient, it’s a waste of resources to build it. Better to spend those resources elsewhere. Dumping megawatts of electricity into heat for inductive charging moving cars is silly. That’s wasted energy better spent elsewhere.
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I’ve wondered for a while how hard it would be to build some power generating capacity into an EV using the rotation of the wheels and copper coils.
In general, that’s counterproductive, the energy has to come from somewhere.
I believe that’s part of regenerative braking on some cars
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There are no free lunches. Every watt of power you made that way would come out of the EV’s batteries, plus more for losses. You’d come out behind.
The closest you can get to this is regenerative braking, which uses the coast-down of the motor during deceleration to recover power. It’s a nice win because you want to slow down and it saves wear on the brakes as well. You don’t come out ahead of course, it’s just a modest amount of damage control for power wasted climbing hills. You don’t even break even (brake even? Nyuk nyuk) because of efficiency losses, once again.
The Chevy Bolt did this particularly well. I hardly ever used the actual brakes when I drove around. The regeneration handled everything except panic stops.
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Maybe we just haven’t come up with a creative enough placement of magnets…
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It’s an interesting idea. I think the best thing would be to build an overhead system like trains and trams use, and some buses, and restrict it to supplying large vehicles which regularly drive long distances.
I don’t think it’s practical or necessary for private cars to charge while they drive. Private cars spend most of their time parked. That’s the best time to charge them. Even on long journeys, you stop occasionally for a break. That’s when you recharge your car. There just need to be more chargers in motorway service areas.
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21st century traffic jam.
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