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Electric cars

Electric cars and vans use an on-board rechargeable battery to store electrical energy. The battery is recharged by connecting it to an electricity supply (usually the 'mains'). When required, energy is drawn from the electric-cells and converted to motive power by the use of an electric motor.

• How do electric cars work?
• How do I recharge an electric car?
• Are electric cars better for the environment?
• What are the costs of owning an electric car?
• Where can I buy an electric car?

How do electric cars work? Return to top

Although the lead-acid battery has been the most widely used traction battery to date, the latest generation of rechargeable traction batteries include nickel metal-hydride (Ni-MH) and lithium-ion (Li-Ion) cells. These provide a significant improvement in performance and range. Despite their relatively high cost, these new battery types have proved to be well suited to automotive applications and are now preferred by most BEV manufacturers.

Driving an electric car is a very different experience to using a conventional vehicle. Forward drive is usually selected in much the same way as in an automatic – another similarity is that there is no clutch pedal. On depressing the accelerator, an electric car initially moves in almost total silence, which can be a little disconcerting. As the speed picks up, the small amount of 'engine' noise that can be heard is drowned out by wind and tyre noise, which become more noticeable as the speed increases.

Most electric vehicles have good acceleration (especially at lower speeds) and are more than capable of holding their own in city-driving conditions. Although most commercial models are designed as city cars and will 'top-out' at 40-50 mph, electrics can be high performance vehicles – the Tesla roadster is capable of 130 mph and goes from 0 to 60 mph in 4 seconds!

While most electric cars do not match the performance of conventional vehicles, current UK models have a range and performance that is adequate for many applications including: city driving, regular drive cycles (such as delivery routes), short range trips (up to 60 miles per day) and where only zero or low emission vehicles are allowed access. As a result, electric cars are most suited for use as 2nd private cars for city use, in commercial fleets (for small loads), and as company 'pool' cars.

How do I recharge an electric car? Return to top

Electric vehicles can be slow- or fast-charged. The most common method is overnight charging, which typically takes 6 to 8 hours. A slow-charging unit comprises a transformer to reduce voltage and a rectifier to charge the cells using direct current. Fast charging units usually require the use of alternating current – these can take as little as 10 minutes for a 50% charge.

Given the coverage of the national grid, it is relatively easy to install recharge points as compared with other green fuels. For slow charging, all that is required is access to a standard 13 Amp socket. However, private users without access to a garage or a private road will have to rely on the availability of 'on-street' roadside recharging points.

The location of electric vehicle charging points is continually changing as more and more new points are installed. For an up to date map displaying location, fees and other information about each recharge point in the UK, visit Newride.org.uk

A national network of on-street recharging points is currently being developed and is strongly supported by the government through the Plugged-In Places programme. The level of coverage is to likely to significantly improve in city centres in the next few years. However, for the foreseeable future, unless you drive in central London, most users of electric vehicles will have to rely on home- or fleet-based recharging locations.

Are electric cars better for the environment? Return to top

Electric vehicles are zero-emission at point of use. However, emissions are produced during the generation of electricity, the amount depending on the method of generation. Therefore, the emissions need to be considered on a lifecycle basis – so as to include power station emissions.

Taking greenhouse gases into account, electric vehicles charged using average 'mains' electricity show a significant reduction in emissions – the figures suggest a reduction of around 40% compared to petrol. This benefits is mainly due to the fact that electric cars are more energy efficient than conventional vehicles. So-called 'regenerative braking', which returns energy to the battery when the brakes are applied, also improves fuel efficiency by up to 20%. If renewable or 'green tariff' electricity is used, then lifecycle greenhouse gas emissions are effectively zero.

Using average 'mains' electricity, some lifecycle regulated emissions such as particulates, nitrogen oxides and sulphur oxides are actually increased. However, as these are emitted from power-stations which are well away from urban areas, their overall impact tends to be much less than when emitted from the exhausts of petrol and diesel cars. As is the case with greenhouse gas emissions, if renewable electricity is used, then lifecycle regulated emissions are also virtually eliminated.

What are the costs of owning an electric car? Return to top

Electric vehicles are significantly more expensive to buy than their petrol or diesel equivalents. Typically for new car or small van the price is increased by up to 80% (i.e. almost double) in cases where the battery is purchased outright. Due to their high cost, batteries are often not included within the purchase price, and are leased on a monthly basis. If the battery is purchased outright, a further purchase is required every 3 to 5 years for battery replacement.

Additional costs are also incurred by electric vehicle users who install recharging equipment. Costs per standard charge point are of the order of £500-£2000, depending on the difficulty of installation. Fully installed fast-chargers cost between £10,000-£30,000 per point (depending on whether an on-board or off-board fast-charging system is used).

On the plus side, electric cars and vans are exempt from 'road tax' (Vehicle Excise Duty) – owners of electric vehicles will therefore save around £100 per year compared to an average conventional car. Fuel costs are also very low due to the competitive price of electricity (fuel duty is zero-rated) and to the high efficiency of the vehicles themselves – fuel costs can be as low as 2.0-2.5p per mile (depending on tariff). For an annual mileage of around 10,000 miles per year, switching from a conventional to an electric car or van could save you around £800 in fuel costs alone.

For drivers in and around London, the other major running cost to consider is the Congestion Charge. All electric cars currently receive a 100% discount on the London Congestion Charge (although vehicles need to be registered and pay an annual £10 fee). With a £8 payable daily charge, this could provide a potential annual saving of up to £2000 – and is the reason that most UK BEVs are currently sold in London.

As part of the UK government's drive to increase the number of electric vehicles, from January 2011, buyers of eligible electric vehicles will receive up to £5,000 under the Plug-In Car Grant scheme. WhatGreenCar will update this page when more information is available.

Where can I buy an electric car? Return to top

Although electric vehicles have been available for decades, only recently have the main-stream manufacturers invested in high quality electric models which aim to meet the needs of twenty-first century road users. This has involved improving driving performance and reducing the vehicle price. A new recharging infrastructure is also being developed at a faster pace, with government schemes in place to help widen the UK recharging network.

A number of specialist 'EV' companies have recently launched a range of small electric vehicles designed for city use. These include the Reva G-WIZ micro-car (imported from Bangalore), the MEGA City Car, and the TH!NK City. More recently, mainstream car makers such as Nissan, MINI, Smart and Mitsubishi have begun to gear-up for electric car production including the Nissan LEAF, MINI E, Smart Fortwo and the Mitsubishi i-MiEV. If the current level of announced government support continues, most of the major manufacturers are likely to launch a electric model in 2011.

Most notably, Nissan are set to manufacture the LEAF electric vehicle, with sales starting in February 2011. This will be the first 'affordable' family zero-emissions vehicle in the UK – the LEAF will be priced at £23,350 in the UK, including the planned £5,000 Plug-in Car Grant purchase incentive.