Smart EV charging shown effective at managing grid demand
September 4, 2019
Managed or smart charging is effective at shifting electric vehicle (EV) charging demand away from peak times and is popular among mainstream consumers, according to research undertaken as part of a UK Transport Research Laboratory (TRL) Consumers, Vehicles & Energy Integration (CVEI) project.
Without intervention, the increased uptake of EVs could add significantly to existing peak electricity demands and could lead to issues in supply-demand balancing and local network capacity. However, managed charging decreased average charging demand during peak times (4 to 6pm) by about 70% compared with unmanaged charging.
The appetite for managed charging among mainstream consumers is very strong, with more than 80% of consumers choosing a managed charging scheme in a post-trial survey.
User-managed charging, where consumers choose when to charge against a time-of-use tariff, was the most popular option with mainstream consumers, and successfully shifted demand to later in the evening. Supplier-managed charging, where consumers were incentivised to give control of the timing of charging to the energy supplier, provided the greatest reduction in peak demand. The experience of supplier-managed charging was also found to make consumers more likely to choose it.
“As we move towards a future of electric transport in a bid to decarbonise, being able to manage the demands that a large volume of EVs will place on the UK’s energy infrastructure is crucial,” said Neale Kinnear, head of behavioural science at the TRL. “With this latest research into mainstream consumer charging behaviour, we have generated an evidence base showing that managed charging is not only highly effective at shifting demand away from peak times, but it is also more appealing to the majority of mainstream consumers. This is a really positive result and gives us confidence that managed charging is an effective solution that appeals to the mass market.”
The trials focussed on mainstream consumers to gain an understanding of the attitudes and behaviour of the mass market. The results demonstrate how mainstream consumer charging behaviour can best be influenced by using alternative types of managed charging schemes, to enable a smooth transition towards a future of EVs.
“These trials represent the world’s first trials of mainstream consumer charging behaviour with both fully electric vehicles and plug-in hybrid electric vehicles,” said George Beard, TRL’s head of ULEV consumer research and technical lead for the CVEI trials. “We provided 24/7 mainstream consumers with experience of using and charging an EV for an eight-week period. This enabled us to capture the most comprehensive dataset on mainstream consumer charging behaviour to date. The charging trials formed a crucial part of the CVEI project and allowed us to address gaps in evidence around mass market user behaviour.”
Across the trials, two types of managed charging schemes were investigated: user-managed charging involved incentivising users to charge at times when electricity demand was low, akin to a time-of-use tariff; supplier-managed charging encouraged users to plug the vehicle in for as long as possible, specifying the charge they required and the time that charge was needed by, and then leave the timing of the charge to be managed by the supplier.
Mainstream consumers found managed charging schemes even more appealing if they offered high annual cost savings, if peak electricity costs were not disproportionately high, and if an override function was provided whereby users could change settings mid-charge. Installing nearby public charge points may also boost the share of consumers willing to choose managed charging, suggesting public charging infrastructure has an important role for increasing consumer confidence.
The trial also showed that consumers value the benefits of being able to interact with managed charging via an app on a smartphone or tablet; in particular, consumers made frequent use of the ability to set personal defaults, negating the need for them to input their preferences every time they plugged in the vehicle. This shows that engagement with managed charging can be further encouraged by making it as easy as possible for consumers.
The CVEI project was commissioned and funded by the Energy Technologies Institute and delivered by a TRL-led consortium that included Baringa Partners, Element Energy, Cenex, EV Connect, Behavioural Insights Team, EDF Energy and Shell.
Established in 1933 within the British government as the UK's Transport Research Laboratory, TRL was subsequently privatised in 1996. Today, TRL has more than 1000 clients across 145 countries. Core areas of expertise include: infrastructure asset management and asset technologies; intelligent transport systems and traffic operations; sustainability and healthy mobility; vehicle safety engineering and technology research; major incident investigations; and human factors safety and behavioural science.