Vehicle-to-grid chargepoints can improve battery life in electric vehicles and reduce carbon emissions and costs of charging, a government-funded project has found.

Research from the EV-elocity project shows that, by careful charging and discharging, EV battery degradation can reduce by one-eighth, and, in some situations, up to 450 kg of emitted carbon dioxide (CO2) or £400 could be saved per vehicle each year.

Vehicle-to-grid (V2G) can balance the calendar and cycling aging (both of which affect the rate of battery degradation) to optimise the battery condition and improve its health by 8.6 – 12.3% over one-year’s operation, compared to conventional charging alone - equivalent to one extra year of use.

In cost-terms, V2G tariff optimisation can save around £100 per year per charge point on normal business electricity tariffs, with up to £400 saved on a smarter tariff.

If managed to maximise the environmental benefit, nearly half a tonne of annual CO2 emissions can be saved, and significant savings (over 180 kg) can be made even when reducing cost is the main goal.

Chris Rimmer, Infrastructure Strategy lead at Cenex and the project’s lead project manager, said: “Our conclusions show that it is not necessary to trade-off financial, environmental and asset lifetimes when charging Electric Vehicles. Cost, carbon, and conditioning benefits can all be gained when V2G is used intelligently with fleet vehicles.”

Professor Lucelia Rodrigues of the University of Nottingham added “a key challenge for an optimum application of V2G technology is to synchronize the needs and requirements of the users and the energy and transport systems. Our work correlated variables such as user needs, mobility patterns and renewable electricity generation to evolve different possible scenarios for the application of V2G chargers, with a view of maximizing local renewable energy consumption, lowering costs for the user, improving battery life and reducing carbon emissions from the whole system.”

“Our experimental research highlighted the potential to extend battery life by exploiting the unique capability of V2G chargers to both charge and discharge the vehicle battery”, commented Professor James Marco of WMG, University of Warwick. “By careful optimisation of this process and knowing how the battery performance may degrade over time, it is possible to condition the battery to extend its life in a number if situations when compared to conventional methods of vehicle charging.”

The EV-elocity Project was funded by Innovate UK, the Department for Business, Energy and Industrial Strategy, and the Office for Zero Emission Vehicles between September 2018 and January 2022; it was led by Cenex and comprised CrowdCharge, Leeds City Council, Nottingham City Council, University of Nottingham and University of Warwick in a second phase from January 2020.

The project deployed 15 chargepoints across nine sites - including West Midlands Police, Leeds City Council and the University of Nottingham Creative Energy Homes campus. Two of charger from eNovates and Nichicon were managed by a technology-agnostic operating system, demonstrating V2G across the different trial sites within the UK.

The final report presents the findings and lessons learned for future vehicle-to-grid deployment.

Ends

Notes to editors:

The EV-elocity project is part of the Vehicle-to-Grid (V2G) competition, funded by the Department for Business Energy and Industrial Strategy (BEIS) and the Office for Low Emission Vehicles (OLEV), in partnership with Innovate UK, part of UK Research and Innovation.

In January 2018, OLEV and BEIS announced that 21 projects (8 feasibility studies, 5 collaborative research and development projects, and 8 real-world v2g trial projects) were to receive funding of £30m to develop the business proposition and the core technology to support Vehicle 2 Grid deployment in the UK, including its demonstration with large scale trials.

The projects involve more than 50 industrial partners and research organisations from both the Energy and Automotive sector, marking the largest and most diverse activities on V2G in the world, and trialling more than 1,000 vehicles and V2G charger units across UK.

The V2G projects represent a significant step towards the transition to a low carbon transportation and a smart energy system. Allowing EVs to return energy to the Power Grid when parked and plugged for charging, will increase Grid resilience, allow for better exploitation of renewable sources and lower the cost of ownership for EV owners, leading to new business opportunities and clear advantages for EV users and energy consumers.