Learnings

Outcomes

Work package two found that there were eight other projects which have demonstrated this technology, but only one supplier worldwide. It also found that there would be work needed for it to comply with all the existing standards which surround things on highways, electromagnetic emissions, and cyber security.
The third work package was a modelling task based on a case study location. This found indicative demands for a vehicle passing over a DWPT system, and then combined this with the traffic modelled in the area, the expected state of charge, and how that would vary throughout the day. This found that for various scenarios, it would add to the demand at the evening peak as most people are travelling home from work with a car that would be at lower charge than in the morning. This means it will not help us as a DNO with our flexibility aims, in a way that conductive charging could.
The fourth work package looked at the business case from the charge point operators’ point of view, to determine if a DNO should expect to see these on the network soon. This found that the best business case was marginal at best, which is to fit the vehicle receiver coils to Heavy Goods Vehicles, and lay DWPT on motorways. This is because HGVs spend a lot of time on motorways and fitting DWPT there would amplify the effects of the installation. The case from the DNOs point of view for this technology was that it would allow us to provide charge to HGVs in a more distributed manner, and allow us to install DWPT in areas which currently have spare capacity and avoid the need for expensive reinforcement. However, there are numerous technological and regulatory barriers to its uptake in the UK, and as a result, we are not expecting to receive connection requests for these in the near future.
A Draft paper was submitted for peer review, titled Determining the social, economic, political and technical factors critical to the success of dynamic wireless charging systems through stakeholder engagement
https://www.mdpi.com/journal/energies/special_issues/Wireless_Transfer

Lessons Learnt

• DWPT operates at frequencies between 10 and 100 kHz, often centred on 85 kHz, and requires AC/DC and DC/AC converters to increase the frequency of power supplied, this could have an impact on power quality depending on the efficiencies and how the technology is being utilised.
•  Variations in air gap, lateral alignment and longitudinal alignment, mean that DWPT systems must be designed to give acceptable power transfer efficiency when misaligned.
•  DWPT deployments should adopt a modular design to allow for scalability and reduce distribution network impacts. All DWPT solutions consist of a Management Unit (MU), Ground Assembly (GA) and Vehicle Assembly (VA) for which the MU and GA is controlled by the installer of the coils.
•  The take up of this technology will depend heavily on vehicle manufacturers adopting this technology and installing VA (Vehicle Assembly) or receiver units on their vehicles.
•  A total of eight DWPT demonstrations or deployments have been identified around the world with most projects focusing on supplying power to heavy vehicles such as trucks or buses. This is significant as at this stage of the technology lifecycle, it is not deemed feasible for privately owned passenger cars.
•  ElectReon is the only active participant in the DWPT market at present.
•  Early learning has determined that the lack of comprehensive standards across all the elements of technology, installation and use of DWPT is currently a risk for future deployment. To avoid problems of interoperability, tailored standards on the type and placement of receiver coils, compliance with roadway construction and safety regulation to standards of service, information sharing, data collection and payment will be required.
•  Power Quality – DWPT systems are made up of various electronics that will have an impact on the power quality at the point of connection to the network. Impacts such as harmonics are discussed within the report but can only truly be detailed using a live trial.
•  The cost to install DWPT is at a best case scenario three times more expensive than traditional conductive charging. This is taking into account the most likely scenarios and comparing with traditional methods. This is a significant barrier to wide scale rollout and for DWPT to be realised in the UK either the costs of purchasing and installation will need to be reduced or the costs per kWh will increase significantly to outweigh any potential savings through reduced battery sizes.