Northern Ireland van insurance customers are being advised to do their bit for the environment while the UN climate change summit is taking place in Copenhagen – and they could bring down the price of their premiums in the process.

Mobile resource management experts Trimble recommend that van insurance customers switch off their vehicles' engines when they are stuck in traffic or a rush-hour standstill, something they say under five per cent of drivers currently do.

"If a driver is parked at the side of the road to complete paperwork or make a call, or [is] even making a delivery which lasts more than ten seconds, the engine should be switched off," suggests managing director Andrew Yeoman. "Idling the engine for more than ten seconds uses up more fuel than switching off and restarting again."

According to Yeoman, enough fuel to drive one mile is wasted for every two minutes an engine is left idle. He cites recent tests carried out on a lorry fleet which illustrated that reducing daily idle time from an hour to 10 minutes could save businesses £614 per lorry since 564 fewer litres of petrol would be needed.