Charge your electric car as you drive
Like a scalextric toy, concept vehicle gets its power from the road it is driving over
THOUGH electric vehicles (EVs) are considered, by some, as the undeniable future of emission-free mobility, slow recharge times, limited battery capacity and range anxiety have so far been a barrier for mass adoption. But imagine an EV that, like a scalextric toy car, gets its power from the road it drives over.
Wireless battery charging is nothing new. Most smartphone brands are now offering ways to recharge by simply placing a device on an inductive pad, and more and more cars are coming out with these cable-free charging systems built into centre consoles. Some car companies are even offering garage-size wireless charging pads for EVs to park on and soak up electricity overnight, without having to plug-in the vehicle.
But now this tech is being taken a step further with a new dynamic wireless electric vehicle charging (DEVC) concept that could enable a theoretically unlimited range for electric vehicles. Similar to how induction stove hotplates work, special coils and electric cables are buried under a road’s surface, and as an EV drives over it an electromagnetic field is absorbed as energy which can be used to either recharge batteries or power electric motors directly.
Renault, together with American telecoms giant Qualcomm, recently conducted a test with a specially-equipped Kangoo Z.E. which drove over a 100m test track underlaid with inductive cabling, and the EV recharged wirelessly at a rate of 20kW at speeds around 100km/h.
Qualcomm’s system featured exposed induction coil plates, but in practical use they could be up to 150mm below a tarmac surface, and energy transfer is said to be unaffected by rain, snow or ice.
Honda, a brand which currently offers no all-electric vehicles and has been a devout supporter (and developer) of hydrogen fuel cell tech, is also now dabbling in the DEVC concept. Earlier this year it tested a system with much higher outputs of 180kW at speeds around 155km/h.
It all may sound like a perfect solution to extended EV range but DEVC comes with its own set of challenges. As with normal EV recharging stations, infrastructure is a major limitation, and it would be very expensive to retrofit even a small road network with underground induction cabling. Standardisation is also a problem, and if car brands are already struggling to agree on a uniform EV charging receptacle (plug), how will they agree on one much more complex DEVC system?
Studies have also associated health issues caused with leaking magnetic flux from inductive power transfer (IPT) pads. Exposure to electromagnetic fields is a subject of ongoing debate, and effects on the human body vary greatly on the type of frequency, strength of current and length of contact. Various studies have proposed that some, even if very small, biochemical reactions occur when in close proximity to these induction systems.