CENEX – WiCET: Sparking a Wireless Charging Revolution on UK Roads

The past decade has seen a big spark in the global electric vehicle market. The number of EVs on the roads, the amount of research and development underway, the technological advances, and the demand from the market has accelerated with electric pace. But the idea of electrical transport is not new. Using rechargeable batteries to power cars is not novel. The jumps forward are down to climate change and emission reduction demand from the global public, and the coming together of ambitious organisations into ecosystems that generate concepts for change.

As organisations of all kinds come together to develop ideas in this space – how to charge quicker, how to reduce emissions further, how to reduce costs, how to create more capacity, how to finance the market etc – powerful progress occurs.

Nowhere is this environment demonstrated better than at the WiCET demonstrator project in Nottingham, UK. WiCET (Wireless Charging of Electric Taxis) is advancing knowledge, experience, and understanding of how vehicles can be charged without a plug in cable system to provide flexibility and reliability. Funded by the Office for Zero Emission Vehicles (OZEV) and Innovate UK, WiCET is managed by Cenex, an independent not-for-profit company involved in the research and development of lower emission transport and energy infrastructure. Seven organisations are part of a consortium that makes up WiCET: Cenex, Nottingham City Council, Shell, Coventry University, Hangar-19, Sprint Power, and Transport for London.

POWERFUL GRAZING

Technical Consultant and Project Manager at Cenex, Richard Sander tells Energy Focus that through the WiCET project, a clear demonstration of what is possible has been achieved following a successful trial which saw specially modified taxis charge in the rank as they waited for the next fare – no plugging in, no wires, no challenge with payment.

“I tell people this is like grazing,” he says. “The idea is not that people turn up and get a full charge. It’s more that they go for regular, smaller top ups. They top up at each visit to the rank as needed and keep the level at a usable mid-range point.”

The trial sees taxis park over an inductive charging pad allowing transfer of power as they wait in the queue for their next fare. Power is supplied to the ground pads through a dedicated cable under the road, and then transferred wirelessly to a receiving pad on the vehicle. The system can detect each car and differentiate from the rest of the fleet. Drivers are then billed through a web-based app, seeing how much power they have used, not even needing to step out of the car. Taxis have formed the basis of the trial, but the potential for future application is significant.

“We have five charging pads in the ground, nine vehicles (five LEVC TXs and four Nissan Dynamo eNV200 taxi conversions) which are fitted with the prototype system,” explains Sander.

“We have had conversations in other areas and there is interest from organisations looking at accessibility needs. There has been discussion around emergency vehicles like ambulances that don’t want to be plugged in. There are trials in other countries with buses, it could be used for on-street parking where people don’t have a driveway or garage and you don’t want cables running across the pavement. There are many potential applications for it and our conversations are not solely focussed on taxis, but there is a way to go before we move to a new trial.”

Critics highlight efficiency as a flaw in the wireless charging concept, but the WiCET project has delivered admirable results. “It is something that we have measured during testing, and we have data that shows it is around 90% efficient and that is comparable to some conductive methods,” details Sander, a mechanical engineer by training, with experience across emissions reduction project management with global businesses including Jaguar Land Rover.

Of course, safety has been top of the priority list and Cenex and project partners have ensured optimum performance within a strict set of standards. The charging system uses a resonant induction method and the charging pad is protected by a light curtain which, if broken, stops the charging. When any obstruction is cleared, charging can safely restart.

“Within the trial we have backup systems that can detect foreign metal objects on the pad. This is important as they can heat up quite quickly. We also have the living object protection system around the car as there is a small residual EM emission field that is generated from the ground pad. In terms of the evolution of the system and the technology this is very important and there are standards to meet. We are very aware of emissions and safety as crucial components in the trial and we have embedded systems into the project to ensure successful deployment,” confirms Sander.

DEVELOPING KNOWLEDGE

The charging pad – on Trent Street in Nottingham city centre, outside the main council building – is limited to 11 kW by SAE (Society for Automotive Engineers) standards. Globally, trials have been run at 22 kW and 50 kW but these sit outside of SAE standards at the time of the project. is hopeful that the WiCET trial will also be useful when it comes to informing bodies on the correct standards to be uniformly applied as the industry grows and as the concept is taken forward.

“We really want it to go somewhere and there is lots of interest from other cities, other local authorities, and other regions – we’ve had enquiries from around the world,” he says. “There are a few WPT system suppliers in various countries, and there is interest in performing further trials in places like London which could obviously be a hot spot for an idea like this.”

The trial will complete at the end of January and will be followed by a reporting period before closedown in March. The hope is that WiCET will have proved the concept and the next stage can be a big step forward, speeding up the electrification of urban highways.

“Projects and trials should be progressive. The next one needs to move the technology forward towards commercialisation addressing barriers that have been identified during this trial,” Sander suggests.

Most of the world’s major automakers have invested heavily in vehicle electrification, and most are now targeting industry-leading status as they research and develop both efficient electric drivetrains and effective charging systems. Renault, Volvo, Nissan, Toyota, Ford, Tesla, BMW, Hyundai, and more have all been part of trials and tests around passenger vehicles.

There will be more engineering and re-engineering before wireless charging is ready for universal delivery, but the likes of Cenex and the WiCET consortium are all vital on the journey. If taxis and some commercial vehicles can be converted to charge wirelessly, significant emission reductions could be achieved in a relatively short period of time. 2021 CO₂ emissions from transport sat at 107.5 million tonnes, 14% lower than 1990 showing the need for continued focus on making it easy to switch to electric where possible.

“We have retrofitted the system to existing vehicles and that involved piggybacking on the native onboard CHAdeMO system that controls the vehicle’s charging. Doing that as a retrofit has a lot more challenges than it would if you were integrating it into a vehicle at the engineering concept design phase,” says Sander, adding that current issues with component shortages have provided challenges in the WiCET project.

“When the project was given the go ahead, pre-covid and pre-supply chain issues, the environment was different. Right now, the landscape is very different and much more planning is required to get even the smallest things to run the way they should. However, the enthusiasm and belief in the project has overcome the challenges.”

CONNECTED, WIRELESSLY

The relationships with partners have been strong, and Cenex has been keen to develop interest and appetite around the project wherever possible. This is the first public trial of wireless charging of this scale in the UK, “and so everyone has been learning and evolving, and that is exciting,” highlights Sander.

Cenex has global pedigree in projects that have provided significant change, and WiCET has been fuelled by its unrelenting ambition. Nottingham City Council as the host has been vital from an infrastructure perspective; Sprint Power has undertaken vehicle integration and prototyping; Hangar 19 has been responsible for back-office billing systems and the Open Charge Point Protocol (OCPP) interface; Coventry University delivered human factor elements and usability; Shell – a non-grant funded partner – provided a data analysis team; Transport for London was involved as a case study partner; and Lumen Freedom delivered charging hardware.

Conversations about a trial began back in 2018 and when Sander joined Cenex in 2021, he took on the WiCET project, driving it through prototyping and testing, through operation and to completion.

“Vehicles have been with drivers since early October and there have been a few teething problems as you would imagine with a tech project like this but overall it has been a success,” he highlights.

Not only is it clear that the hardware works, it is now obvious that billing and collection is achievable, and drivers are excited about the opportunities to transition to electric vehicles without needing to completely change how they operate. The UK government’s Road to Zero Strategy requires emission reduction in transport, and this comes through innovation but also cooperation and collaboration.

“Future applications will involve OEMs, authorities on the ground, and we will also need charge point operators, distribution network operators (DNOs), and others to come together as a package to make things happen,” Sander insists.

“We need to make people aware of what we have done and what we are doing. Within the EV transition, we must take all opportunities and create complementary alternatives to plug-in charging. There are so many applications where plug in charging is not going to be an ideal solution. Spreading awareness and knowledge about other ideas is crucial,” he concludes.