Bus passengers commuting to the capital are set for a wee boost after Stagecoach announced it is investing more than £9m in a new fleet of environmentally conscious coaches for the Oxford Tube service.

The company has ordered 26 new green double decker coaches which use a solution of the chemical urea – found in urine – to treat the vehicle’s exhausts and destroy the harmful nitrogen oxide that is produced.

The buses, which are used by more than two million passengers a year, are also kitted out with the latest mod-cons.

Passengers will continue to benefit from Wi-Fi internet access, air-conditioning, reclining seats and powerpoints for laptops and mobile phones.

The 87-seat Van Hool Astromega vehicles – costing more than £350,000 each – will be fitted with DAF EEV (Enhanced Environmental Vehicles) engines which have lower emissions than those required by the stringent new pollution-cutting Euro 5 benchmark.

Martin Sutton, managing director of Stagecoach in Oxfordshire, said: “These new state-of-the-art coaches will be among the cleanest and greenest on the road in Europe.

“The Oxford Tube fleet covers 3.4 million miles every year and we want our customers to continue to experience high quality, greener smarter travel.

“This is the third complete fleet replacement for the Oxford Tube we have undertaken in 10 years and it is evidence of our commitment to investing in Europe's premier express coach service.”

The Oxford Tube service is the most frequent express coach service in Europe running 24 hours a day between Oxford and London, with buses departing up to every 10 minutes at peak times.

The service was launched in 1987.

Earlier this year Oxford City Council declared a ‘Low Emission Zone’ in the city centre which requires local bus firms to meet the Euro 5 emission standard by 2013.

Oxford Bus Company currently has 42 Euro 5 standard buses, representing a third of its fleet.

In March, Stagecoach admitted it had already invested in 48 coaches in Oxford over the last year that were only up to Euro 4 standard. The company says the engines of the new Oxford Tube buses use a constant feed of urea solution and a passive soot filter to make the vehicles even cleaner than those fitted with compressed natural gas engines.

Deliveries of the fully wheelchair accessible fleet will start at the beginning of next month and will be completed by early October.

cwalker@oxfordmail.co.uk