The growth of electric vehicles (EVs) presents a new challenge for the UK’s electricity transmission and distribution network operators. As groups of neighbours acquire EVs, localised clustering is likely to have an impact on electricity networks. Therefore, a large investment has to be made to strengthen the existing grid. The Electric Nation project researched if smart charging, provided by GreenFlux, could avoid the need to perform expensive network upgrades.
The Electric Nation Smart Charging project ran from 2016 to 2019, focussing on domestic EV charging. In total, 673 smart chargers were installed at participants’ homes throughout Western Power Distribution’s license area, involving more than 40 different types of electric vehicles.
Via GreenFlux’ smart charging system, transaction data was gathered (plug in and plug out, active charging session, amount of energy consumed). The GreenFlux back-office system could monitor the overall demand of chargers and could reduce this total demand by instructing individual chargers to reduce the power available to charging EVs.
Trial 1 – experience smart charging
Participants experienced smart charging via GreenFlux, but without telling them when they were being managed. Groups were managed when there was not enough capacity to give all active chargers their maximum allocation. Most likely, this situation occurs when capacity is lowest and/or demand is highest (the weekday evening peak).
Trial 2 – request high priority via a mobile app
In this trial, participants were given a mobile app from GreenFlux to enable them to interact with the smart charging system. Participants were able to view their charging session and request high priority, which temporarily prioritized their current session over others for which no priority was requested. Results show that requests for high priority occurred for 2-3% of charging events, indicating that EV drivers only use it when it is really necessary for them.
Trial 3 – time of use incentives in the app
In this trial, participants could select a charging preference with different time of use (ToU) tariffs in the GreenFlux app: 1) optimise time (charge regardless of price), 2) minimise cost (charge in off-peak period only), or 3) optimise time and cost (charging could begin during the shoulder period, but would avoid the peak price charging). The app also included more information, such as recent transaction history (energy used, time charging and impact on reward value). The results of this trial show that the early evening peak in EV charging demand disappeared. A sharp increase in demand was observed at the cheap, overnight off-peak price boundary. This could have negative impact on the electricity system, but could easily be mitigated by randomised or time-band switching.
Hans de Boer, CEO of GreenFlux: “We are very happy and proud to have supplied our innovative smart charging technology to the Electric Nation project. And the great thing is that we can apply the acquired knowledge about smart charging already today. We are working with different parties in the UK to put smart charging into practice, on sites such as large scale apartment buildings and office buildings.”
To conclude, thanks to smart charging, upgrading the existing grid capacity is not necessary, therefore avoiding the need to make costly investments. In addition, GreenFlux’ smart charging technology supports the introduction and management of Time of Use (ToU) based charging. Time of use incentives appear highly effective and smart charging can provide a means to manage any negative consequences of mass uptake of ToU incentives.
Electric Nation is the customer-facing brand of CarConnect, a Western Power Distribution (WPD) and Network Innovation Alliance funded project. WPD’s collaboration partners in the project are EA technology, DriveElectric, Lucy Electric GridKey and TRL.