A three-year study into how drivers might use electric vehicles and the resulting impact on the energy system has found that up to 95% of people would be happy to use ‘smart charging’ – if it cut their energy bills.

The study also found consumers were also willing to pay more for an electric vehicle (EV) – as long the payback from cheaper running costs was less than five years.

Two sets of trials – a vehicle uptake trial and a charging behaviour trial – were commissioned by the Energy Technologies Institute and delivered by TRL.

The Consumers, Vehicles and Energy Integration (CVEI) study gathered in-depth data from vehicles and charge points for 584,000 miles of journeys and 15,700 charge events, covering both home and public locations, while consumer surveys were undertaken to understand attitudes, perceptions and choices.

Charging Behaviour Trials

• To understand how mainstream consumers (i.e. not “early adopters”) responded to tariffs aiming to shift charging away from peak times of demand (between 4-7pm), in order to reduce strain on electricity networks.
• Consumers were offered one of two types of smart charging – either supplier-managed charging (where suppliers or another third party manage when the charging takes place) or user-managed charging (where consumers choose their own charging time utilising time-of-use tariffs) – as well as a control group without smart charging.
• 247 consumers were given 2 months with either a Battery Electric Vehicle (BEV) or Plug-in Hybrid (PHEV).

Vehicle Uptake Trial

• To understand barriers and motivators influencing mainstream consumer adoption of EVs.
• 200 consumers were given 4 days with each of 3 vehicles, identical in all but powertrain: BEV, PHEV and Internal Combustion Engine (ICE).

The main findings include:

• 95% of Battery Electric Vehicles drivers and 85% with Plug-in Hybrid Electric Vehicles chose smart charging over dumb charging, to automatically avoid charging at times of peak grid demand or when electricity is most expensive.
• Mainstream consumers trialling all three types of car said they were willing to pay more for BEVs or PHEVs over an ICE vehicle, as long as the savings on running costs delivered a payback in fewer than 5 years.

Energy Technologies Institute, Chief Executive Officer, Jonathan Wills said: “The study was the first and largest of its kind, providing 450 mainstream consumers with real-world experience of using both Battery Electric Vehicles and Plug-in Hybrid Electric Vehicles for their everyday journeys.

“The value of doing trials with mainstream consumers cannot be over-estimated because early adopters of EVs, or any technology for that matter, are often willing to put up with limitations, faults and costs that no mainstream consumer would ever accept.

“To put ourselves on track towards Net Zero, we really need low emissions vehicles to become mainstream and this study has produced the most comprehensive picture so far of the issues facing the transition to an electric-powered era in terms of consumer choice.

“This three-year project aimed to do three things: firstly understand the challenges and opportunities of mainstream consumers moving to low-carbon vehicles; secondly, examine the integration of vehicles with the energy supply system; and thirdly, develop insights to help inform UK government policy and shape energy and automotive industry products.”

Vehicle Uptake insights

• People were willing to pay an extra £4.70 in upfront cost (compared to petrol car) per £1/yr saving in running costs – i.e. payback in 4.7 years.
• 90% of mainstream consumers would consider a Battery Electric Vehicles as a main car if its range was increased to 300 miles or a PHEV with 100 miles of range; while 50% would consider a BEV if the range was 200 miles.
• Younger men (under 34) most likely to adopt PHEVs, middle-aged (40-60 years old) male or female most likely to adopt BEVs, older women (over 60) least likely to adopt PHEV or EV.

Energy Systems Catapult’s Infrastructure and Engineering lead, Liam Lidstone delivered technical input and quality assurance of the CVEI study on behalf of the ETI, where he was previously Strategy Manager.

Liam Lidstone said: “The study found that mainstream consumers were willing to pay more for a Battery Electric Vehicle or Plug-in Hybrid EV as long paid back from lower running costs was less than five years.

“Electricity being cheaper than petrol per mile of travel was a key consideration for people considering the switch to a low emission vehicle.”

Charging Behaviour insights

• Mainstream consumers typically charge at peak times for the electricity system (4-7pm) unless there is an incentive not to do so.
• Both user-managed and supplier-managed charging was able to shift demand to later in the evening.
• Mainstream consumers prefer smart charging over simply plugging in and charging straight away, even if the saving from doing so was relatively low (e.g. £12 a year).

Liam Lidstone said: “The study provides compelling evidence for how the increased electricity demand from electric vehicles can be managed.

“We found that different forms of smart charging at home appealed to between 77% and 95% of mainstream consumers.

“Smart managed charging was shown to be highly successful in shifting charging away from peak times of electricity demand between 4-7pm and into the overnight period relative to unmanaged conditions.

“As well as lowering costs for all concerned, this can ensure that EVs are being charged from low carbon generation such as wind power, accelerating the journey towards Net Zero.

“Understanding this potential is essential because it helps to plan effective electricity network reinforcement, make better use of cleaner renewable energy and limit the need for more polluting generation at peak times.

“Without it the costs of the energy system would be much higher, and if you add growing demand from electric heating into the mix, this cost could be even higher still.”

Further details

The Consumers, Vehicles and Energy Integration (CVEI) study was delivered for the Energy Technologies Institute (ETI) by consultants TRL, in partnership with Element Energy, Baringa Partners and Cenex, to determine the barriers and motivators which influence consumer uptake and use of electric vehicles and the impact on energy system infrastructure.

Energy Systems Catapult provided technical input and quality assurance to the project on behalf of the ETI and will take forward ownership of the data and models to provide future development of the CVEI capability from the ETI legacy.

The two-part study, which included trials with 450 consumers, delivered:

• The first and largest trial of mainstream consumer experience using both Battery Electric Vehicles and Plug-in Hybrid Electric Vehicles for day-to-day journeys.
• Detailed data and insight into mainstream consumer behaviour and preferences for different vehicles and under both “conventional” and smart charging conditions.
• Implications of the changes required of energy system infrastructure for the UK to transition to a secure and sustainable low carbon vehicle fleet.
• A Market and Policy Roadmap for decision-makers, including the Electric Vehicle Energy Taskforce.
• The development of an integrated modelling toolset for further research into off-road charging, managed charging, time of use tariffs, etc.

The vehicles used in the CVEI study were an electric VW e-Golf hatchback, a plug-in hybrid Golf GTE hatchback and a standard internal combustion engine Golf hatchback GT Edition.