Connected Kerb is rolling out public wireless charging at existing charging stations

Tags: #ev-ownership

Wireless charging is nothing new – in fact it was discovered in the 1800s. Most new smartphones can be charged wirelessly, but aside from Tesla, very few EVs have the infrastructure in place to benefit from the technology. But that is changing thanks to London-based Connected Kerb and Munich induction charging specialist, Magment.

The partnership between Connected Kerb and Magment will see induction pads being added to existing charging stations, enabling those with wireless-capable cars to benefit. Within the initial roll-out, which will start next year, Connected Kerb will add induction pads – which are sunk into the road (see explainer below) – to a variety of sites. These will include on-street residential parking bays, car parks, public service locations and even taxi ranks – for the carbon conscious cabbies out there.

On that last point, Oslo is well ahead of the game when it comes to electric taxis. In its bid to create the world's first zero-emissions taxi fleet by 2023, the city is installing wireless charging in taxi ranks. Delivering power at up to 75kW, the aim is to ensure the city's taxi fleet can keep moving without disrupting day-to-day business.

The Connected Kerb scheme will be on a smaller scale to start with, using the company's existing charging locations and piggy-backing on its charge points to allow users to connect. So far in this country, induction charging tests have been on a small, localised scale and primarily to charge electric buses. A scheme in Buckinghamshire, London and Milton Keynes run by Char.gy has received £2.3 million in government funding and includes a grant for participants to have a charging pad installed on their EV.

And that's another part of the puzzle; manufacturers are in a situation where they have to make a choice as to whether to save consumers money by not installing expensive charging pads on their vehicles – owing to the fact that the infrastructure isn't there – or 'future-proof' their cars and up the price.

Increasingly, car makers are airing towards the latter option, with VW making all of its forthcoming ID. range wireless-capable, and BMW's 530e having the option of a wireless home charging mat in some markets. Tesla – itself named after the scientist who discovered wireless charging – has had wireless superchargers for several years now. Numerous other manufacturers, including big hitters like Nissan, Toyota and Volvo, are exploring the technology.

Connected Kerb’s CEO, Chris Pateman-Jones is confident that trailing wires is soon to become a thing of the past. He said: “Induction charging will arrive faster than perhaps many people think. Vehicle manufacturers are increasingly including induction charging technology in their new models, but at present, there are only a handful of induction-enabled EV charge points. We aim to change that.

“Induction charging will become a ubiquitous technology over the coming few years, and for good reason. It’s just as fast as traditional charging, however, it’s convenient, simple and provides a compelling user experience.”

With a large and ever-growing market in retrofitting induction pads to EVs that don't already have them – which is a relatively straightforward process – the good news is that the technology doesn't mean anyone need be left behind.

What is wireless induction charging?

Charging without wires doesn't actually require much in the way of exotic materials or electrical witchcraft. In fact, it's mostly about creating a magnetic field between two sets of copper coils. Charging capacity is dictated by the size of the coils and also the distance between them, with a smaller distance meaning better transfer efficiency. In the case of the BMW system on the 530e, 20kW at 85 per cent efficiency power transfer is standard. Anyway, in five steps, this is how wireless induction charging works:

1. Voltage from the supply – usually the mains – is converted to high-frequency alternating current (AC) in the charging pad.
    
2. This AC is sent to the first of the copper coils, in this case the transmitter coil located in the charging pad.
    
3. When an EV equipped with receiver pad, and therefore receiver coil, is parked over the transmitter, the AC current creates a magnetic field which extends to the receiver coil.
    
4. This magnetic field creates a current within the receiver coil mounted on the EV.
    
5. Alternating current is converted to direct current within the EV's charging system. This is directed into the battery, and thus the process of power transfer is complete.