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World’s largest commercial EV Trial reveals new charging insights

The first set of results from Optimise Prime, the world’s largest commercial EV trial, have arrived. They provide interesting new learning on the impact of EVs on the grid and the implications for charging infrastructure and commercial fleet decarbonisation.

The Optimise Prime trials have been collecting journey and charging data from thousands of commercial EVs across the UK since July 2021. The data is building a clear picture of the potential impact of EV growth on distribution networks. Alongside this, the project is trialling the effectiveness of new connection and flexibility services that could reduce the need for network reinforcement as a result of the EV transition - the first results of which are detailed in the new report.
The report’s learnings cover the project’s three trial workstreams - Return-to-Home charging, based on Centrica’s British Gas fleet; Depot charging, based on Royal Mail’s delivery vehicles; and Mixed charging (where EVs charge at a variety of locations) based on analysis of journey data from Uber’s electric private hire vehicles (PHVs) in London.

Key learnings include:

In the Return-to-Home trials we’ve found that unmanaged, the peak charging demand from return-to-home vehicles is likely to occur between 17:00 and 19:00, coinciding with peak demand on the distribution network. However, smart charging has been modelled to reduce significantly peak demand from return-to-home vehicles as long as the load is balanced over a longer period and not just shifted to later in the day. Based on analysis of historical data we expect there to be a significant seasonal variation in power demand from home-charged vehicles and will be monitoring this throughout the trials.

The Depot trials have modelled various smart charging scenarios, demonstrating that smart charging should deliver a reduction of peak demand for the networks as well as energy and connection cost savings for the depot operator. Initial trials and modelling of profiled connections have shown that it should be possible to utilise control of EV charging to keep sites within an agreed profile. However, there may be some sites where there is too little controllable EV demand to do this reliably.
Flexibility trials have shown an ability to control charging in response to flexibility requests from our Distribution Network Operator (DNO) partners UK Power Networks and SSEN. In month ahead products there was a significant difference between forecast and actual demand, and so future trials will look at improving the reliability of forecasting.

In the Mixed Trials, the data from Uber trips has allowed us to model charging events and demand throughout Greater London. Charge demand from PHVs is likely to peak in the evening as some drivers return home and others need to top up, and there is a clear pattern within and across days in trip type and charging demand. We’ve identified a significant number of locations in Greater London where drivers need to travel far (eg. over 2 miles) if they need to charge during their shift due to limited availability of rapid chargers - and in the most popular locations demand is outstripping charge point capacity resulting in use of non-optimal chargers (i.e. those further away from the demand). Throughout the project there has been continual growth in both charge point infrastructure and the average range of vehicles in the mixed trial. Both of these factors will need to be factored into modelling of future charging patterns as we consider how future growth will impact on distribution networks.
The next Optimise Prime deliverable, due to be released later in Spring 2022, will focus on findings related to business models, including economic and behavioural findings from total cost of ownership analysis and driver surveys.

The trials are due to conclude at the end of June - this will be followed by the release of a project data set and final project learnings later in the year. All of the Optimise Prime deliverables can be found on the project website here, as well as the full report here.

Part-funded by Ofgem’s Network Innovation Competition, Optimise Prime is an industry-led electric vehicle innovation and demonstration project that brings together partners from leading technology, energy, transport and financing organisations, including Hitachi Vantara, UK Power Networks, Centrica, Royal Mail, Uber, Scottish & Southern Electricity Networks, Hitachi Europe and Hitachi Capital.

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