Electric vehicles are only as ‘green’ as the electricity that charges their batteries, a report published today by the UK’s leading engineers points out. In Electric Vehicles: charged with potential, The Royal Academy of Engineering identifies the serious challenge of ensuring that the electricity supply system can cope with charging tens of millions of vehicles whilst still reducing carbon emissions from power generation.

In preparing its report, the Academy has identified four major technical issues:

  • the availability of high energy-density batteries at a price and with a long enough cycle life for electric vehicles to be economically viable
  • the practicalities of charging vehicles – particularly for users without off-street parking
  • the electrical distribution infrastructure to provide power to millions of charging points and
  • the need for a national energy system and ‘smart grid’ that can recharge millions of electric vehicles using low-carbon electricity without overwhelming local distribution circuits.

“Swapping gas guzzlers for electric vehicles will not solve our carbon emissions problem on its own,” says Professor Roger Kemp of Lancaster University, Chair of the Academy’s Electric Vehicles working group. “When most electricity in Britain is still generated by burning gas and coal, the difference between an electric car and a small, low-emission petrol or diesel car is negligible. We welcome the fact that the motor manufacturers are so ready to take on the challenge of developing mass market electric vehicles. We also welcome the new Government's commitment to mandating charging sockets for electric vehicles and plug-in hybrids, but establishing these as the technology of choice for personal transport is only one aspect of what is needed to reduce transport emissions.”

The current contribution of renewable and low-carbon generation to the UK’s energy supply is one of the lowest in Europe, the report points out. If the UK is to meet its renewables targets and ensure a greener power supply to electric cars, a range of new low-carbon energy sources will be needed, including new nuclear power stations, wind farms and tidal barrages. As the Academy recognised in its recent report Generating the future: UK energy systems fit for 2050, creating this new energy system will require a massive change programme and robust leadership by Government.

There are three interrelated policy programmes that are critical to the successful introduction of electric vehicles: low-carbon energy, universal broadband provision and smart electricity grids. The report says that electric vehicles can only have a serious impact on carbon emissions if these three areas of policy are already in place. “Delivering all four programmes will be more challenging than any other engineering project of the last century. We have a unique opportunity just now to ensure that all the policies work together and to recognise the critical links between them,” says Professor Kemp. “For example, recent discussions on introducing smart meters to every household did not include the functionality required to manage electric vehicle charging, which could render the first generation of smart meters obsolete as the electric vehicle market grows.”

Richard Parry-Jones, a member of the working group and former Group Vice President of the Ford Motor Company, says: “Electric vehicles could provide a major contribution to meeting the target of an 80 per cent reduction in greenhouse gas emissions by 2050. However, they will only be built in mass production numbers when there is a compelling sustainable social and business model for their use to allow manufacturers to plan for a long-term market and when the new vehicles have a real carbon efficiency benefit over the latest internal combustion engines.”

There are ways to allow electric vehicles and plug-in hybrids to take over most of the present uses of petrol and diesel vehicles but these are unlikely to develop without financial incentives for early adopters. In the medium term, the new Government will need to indicate how it intends to replace road fuel taxation as electric vehicles gain market share, to allow manufacturers and potential users to make informed decisions.

A more likely alternative to widespread adoption of pure electric vehicles with their infrastructure requirement would be the plug-in hybrid. While hybrids have most of the environmental benefits of electric vehicles, they do not rely on such a comprehensive network of recharging points at multiple destinations. Plug-in hybrids could be adopted quickly as family cars or executive cars, leaving pure electric cars to achieve initial market penetration as second cars, doing low mileage and thus having little impact on carbon emissions.

Whatever happens, the introduction of electric vehicles will fundamentally change the way we use and relate to our cars in the future. Car ownership could be replaced by car clubs and shared ownership. “We face an uphill task,” says Professor Roger Kemp. “Cars are iconic and aspirational in a way that most other energy-consuming goods are not and are central to much of our contemporary culture. In Britain, you would not get 6.4 million people tuning in to TV programmes called Top Domestic Appliances or Top Condensing Boilers in the way they do for Top Gear.”

Notes for editors

  1. Electric Vehicles: charged with potential will be published on Tuesday 25 May 2010, available online at the Academy’s web site:
    Electric Vehicles (1.87 MB)
  2. Electric Vehicles: charged with potential was prepared by a working group consisting of the following group of Academy Fellows, commenting in a personal capacity and not necessarily as representatives of their respective organisations:

    Professor Roger Kemp FREng, Lancaster University (Chair)
    Professor Phil Blythe, Newcastle University
    Dr Chris Brace, Bath University
    Pete James, Prodrive
    Richard Parry-Jones FREng, RPJ Consulting
    Davy Thielena, KEMA Consulting
    Dr Martyn Thomas CBE FREng, Martyn Thomas Associates
    Professor John Urry, Lancaster University
    Richard Wenham, Ricardo plc
  3. The Academy is sponsoring a debate at Cheltenham Science Festival on Sunday 13 June entitled Electric dreams: the future of cars. Professor Roger Kemp will join psychologist Harry Witchel and electric car enthusiast Robert Llewellyn to explore the future of battery powered vehicles  www.cheltenhamfestivals.com/science
  4. Founded in 1976, The Royal Academy of Engineering promotes the engineering and technological welfare of the country. Our fellowship – comprising the UK’s most eminent engineers – provides the leadership and expertise for our activities, which focus on the relationships between engineering, technology, and the quality of life. As a national academy, we provide independent and impartial advice to Government; work to secure the next generation of engineers; and provide a voice for Britain’s engineering community.

For more information please contact

Jane Sutton at The Royal Academy of Engineering
Tel. 020 7766 0636; email:  Jane Sutton