Roads that charge your car as you drive

[Fungus]

My point was these costly "charger roads" are not a lot more convenient than existing solutions to the charging problem.

And my point is that that's only your opinion.

There might be thousands of people who think it's a good idea and are willing to pay for it. Only a marketing study will tell the truth.

Trucking companies would almost certainly pay for something that extends the range of electric trucks. Every minute they aren't trucking costs them money.

Politics/opinions aside: Could it be made practical?

Induction is obviously better than rails and the receiver coil can be very close to the road surface. There's no reason why roads can't be built that extend the range of all vehicles that drive along them. Maybe even single lanes of multi-lane roads.

[Fungus]

And to the poster above, saying "inductors, inductors and more inductors...", for your 10Kw inductive charger you lose 10% efficiency per cm, how close to the ground needs to be your "inductor" ?

We have sensors and servos. There's no reason it can't be 0.5cm above the road surface.

[b_force]

Don't get some comments here.
What's wrong with using an old idea with more modern technology?
Most of the things we use today are exactly made that way.

Personally I would be only able to judge if there is actual data available how bad/good it works.

[helius]

What's wrong is forgetting the lessons of the past: that the idea being discussed was inferior in every way to overhead wires and trolley poles. "Modern technology" isn't going to change that.

[b_force]

What's wrong is forgetting the lessons of the past: that the idea being discussed was inferior in every way to overhead wires and trolley poles. "Modern technology" isn't going to change that.

I find that a bit fast way to judge something.

Electric cars were also terrible, yet invented around 1900.
Nowadays they perform a hell of a lot better.

Also, many train networks work on a very similar way every day, except that the system is above the train, not underneath.
So apparently it isn't "that bad"?

[apis]

I haven't seen that one before but I have seen another idea tested closer to where I live:

Supposedly it works well in rain (don't know about snow) since rain will flow off/under the rail. There are mosfets in the rails that only switch on the power when a car is above it, so it can be used somewhat safely in cities or on country roads. Also has the advantage that you can install it on existing roads easily.

Any sort of rail/wire system requires huge investments in infrastructure though, and no one is usually willing to take the risk (neither manufacturers nor road maintainers) unless it is already established proven technology so I doubt much will come off it.

[nctnico]

- Dirt and oxidation: the rail will have to be made of some kind of unobtanium material to be even moderately resistant to oxidation, but you still have dust and leaves and other dirt, in 2-3 months this will need very expensive maintenance or it will be dead, the moving contacts will push crap into the rail. Oh, did I mention dilatation issues in the summer, this is difficult to segment  .
 - Average speed: this dragging contact will reduce the maximum speed to 4-60Km/h at best, or else the mechanical stuff will blow away.

Reading this I very much wonder how electric trains work (either with overhead power, centre or side rails). I think these go faster than 60km/h.

Post like this make me go against my promise, they go faster because they travel on rails, not wobbling with a steering wheel, rails on which if there is a level shift of more than 10cm the whole rail goes under maintenance. Not to mention HUGE curve radius. Also they are using a very high voltage that makes having a relatively low current contact, you can't do this in ground level, exposed rails.
If you want comparable speeds, think about tramways or trolley buses.

But surely trams and trolley busses should be able to move faster than 60km? I've seen 80km/h being quoted for a trolley bus. After all a bunch of contacts on an arm which has some degree of movement (and can detach if necessary) should allow for higher speeds. Still I agree that too much (lateral) movement is probably going to kill this idea if there is a human behind the wheel. Perhaps this idea is more suitable for self driving vehicles together with a seperate charging lane parallel to the normal road. That way you can charge without loosing too much time. However for a charge time of 15 minutes while travelling at 100km/h the charge lane would need to be 25km long. That doesn't sound very feasible to me one way or another (for example if the charge lane is cut into sections of 5km each).

[f4eru]

Hello
This kind of solution is in use in trams already : only the rail segment directly under the tram is energized.
http://www.alstom.com/products-services/product-catalogue/rail-systems/Infrastructures/products/aps-ground-level-power-supply/

https://fr.wikipedia.org/wiki/Alimentation_par_le_sol
I saw the deployment of this tech in Bordeaux, the first city to use it.

It had many many problems at first :
- failures of the isolation slots between segments ( the rails have 30cm of isolated part between segments) those wore out too fast
- water ingress in the switching boxes
- premature failures of the isolation slots again after changing the material
- System too costly : a dual solution was deployed, only the historic centrum was equipped with the APS
- premature failures of the isolation slots after changing the material again
...

2 Years after the deployment of the APS, the bordeaux city transportation company was mastering the art of replacement busses as a side effect of this.
But now it's quite reliable.

Concerning cars, I don't think it's a good solution, because the rumbling of the contacts over the segment boundaties every 20m will be disturbing for people, and also economics are not very good for that kind of system, compared to a simple plug charger. EVs have sufficient range now, and you need to stop on long trips for pauses anyway. There's no real point for consumers, I think.
But perhaps for some niche application, especially trucks on some high frequentation roads, it could be a thing.

Concerning costs :

Le surcout de la solution APS, d'alimentation par le sol, serait de l'ordre de 2,5 millions d’euros par kilomètre et de 50 000 € par rame

2.5 million/km and 50k per vehicle. That's the additionnal cost compared to a classical overhead line solution.

[apis]

The best proposed solution to the range/charging problem that I have seen is to use standardised batteries which you can replace (quickly and automatically) at the "gas station". But that would require the EV-manufacturers to settle on some battery standard.

[JacobPilsen]

That rail bring to mind: Jurassic Park.

[DougSpindler]

What prevents a little kid from poking a large paperclip in the outlet in the street and getting "charged" or should I say charred.

[helius]

80 km/h is completely reasonable for a trolley bus. But there is a big difference in the length of the trolley pole and its ability to swing to maneuver around obstacles. If the pickup is centered in the center of the traffic lane it will be all but useless in a situation where any maneuvering takes place.

Trolley busses not infrequently do come off the wires, and this is something that needs to be taken into account when planning traffic patterns. At least they can be safely reattached by the operator, since the control ropes are insulating and they can simply be pulled into position. I think everybody knows there is no way to safely adjust a ground-level pickup while the path is energized.

[DougSpindler]

What if a vehicle becomes disabled on the track?  Is there anyway to move it and get it out of the way? 

My wife has an electric car and once an airbag deploys the car can’t be moved.  My wife was on the freeway when this happened.  The car could have under it’s own power be driven 30 feet or rolled the 20 feet to get it out of the middle of the road.  But nope, once on of the car’s airbags deploys the car can only be moved by dragging it.

[Fungus]

What if a vehicle becomes disabled on the track?  Is there anyway to move it and get it out of the way? 

My wife has an electric car and once an airbag deploys the car can’t be moved.  My wife was on the freeway when this happened.  The car could have under it’s own power be driven 30 feet or rolled the 20 feet to get it out of the middle of the road.  But nope, once on of the car’s airbags deploys the car can only be moved by dragging it.

Yep. They disconnect the batteries internally for safety reasons. You want to place a load on a possibly damaged lithium battery? One with hundreds of other batteries around it?

[metrologist]

  I thought these things were so safe that people build their home walls with them...