Monday 10 May 2010

Electric car drivers fear being stranded with flat battery

Ben Webster, Environment Editor

The era of carefree motoring may soon be over, according to a study which reveals that drivers of the new generation of electric cars are plagued by nagging fears of being left stranded by a flat battery.
They narrow their horizons and rarely venture far from home, abandoning the old notion of the freedom of the open road.
A six-month trial involving 264 drivers found that almost all experienced “range anxiety” and travelled only short distances.
They were over cautious when planning journeys and allowed themselves a generous safety margin to avoid the need to recharge en route. They tended to avoid using their cars if the battery indicator showed that the charge level was less than 50 per cent.

Even though electric cars such as the Mitsubishi i-MiEV are theoretically capable of travelling 100 miles between charges the drivers appeared not to trust the official figures. The maximum journey undertaken was only a quarter of the official range.
The suitcase-sized batteries take at least six hours to recharge and Britain has only about 300 public charging points, most of which are in London.
The Government-funded trial, involving drivers working for local authorities, private companies and universities in the North East of England, found that the maximum journey length undertaken was only a quarter of the car’s official range.
Cenex, the Centre of Excellence for low carbon vehicle technologies which conducted the trial, concluded: “Range anxiety effects were significant throughout the trial with 93 per cent of journeys commencing with over 50 per cent battery state of charge.
“The under-utilisation of range is undesirable in terms of efficient deployment and acceptance of electric vehicles and highlights a need for more sophisticated on-board range prediction aids.”
The trial also found that drivers altered their driving style, slowing down and avoiding unnecessary acceleration or braking when the charge indicator dropped below 50 per cent.
Neil Butcher, who is leading a Government-sponsored trial of 25 electric cars in the West Midlands, said that drivers tended to think much more carefully about their journeys before setting out.
However, he said that only one family so far had drained the battery and been forced to make an unscheduled stop.
“They were driving at high speed down the motorway on the first day they had the car and they ran out of charge about four miles from home. They stopped at a pub which let them plug in while they sat there for a couple of hours until there was enough to make it home.”
Mr Butcher said that range anxiety increased in cold weather because the battery capacity fell by up to a third. Using the heater also caused the range shown on the dashboard instrument to drop by up to 20 miles.
“It encourages you to wear a coat and gloves in the car,” said Mr Butcher.
He said that drivers would be confident about making long trips once a network of fast-charge points was deployed. These give an 80 per cent charge in as little as 20 minutes. However, these points cost up to £25,000 each to install and using them reduces the life of the battery.
David Jackson, electric vehicle project manager for Nissan UK, said that drivers of the Nissan Leaf, a small family electric car due to go on sale in March next year, would be able to use a mobile phone to monitor the battery level as it was recharging. They would also be able to send the car a message to warm itself up using mains electricity so that they could start at a comfortable temperature without shortening the car’s range.
From January drivers will be able to obtain Government grants of up to £5,000 towards the purchase of an electric car.
The Department for Transport has also given London, Milton Keynes and the North East a total of £8 million for the installation of 11,000 charging points by the end of 2013. The points will mainly be installed in car parks and at leisure centres, railway stations and supermarkets.
However, only 2,000 points will be installed next year and only 79 of those will be fast-charge points.