A biomethane bus project in Lincoln is up for a top national award.
The green BioBuses are a familiar sight on roads around the historic Cathedral Quarter of the city.
After passenger numbers rose by 11 per cent following their introduction last May, operator Stagecoach has been named as a finalist in the UK Bus Awards 2012.
The fleet of 11 vehicles runs on a mix of biomethane and diesel.
And the company says a reduction in congestion and pollution has helped it to make the shortlist for the Environment Award.
Managing director for Stagecoach East Midlands, Gary Nolan, said the scheme was the first of its type in Lincoln.
"We are delighted to have reached the final of the 2012 UK Bus Awards," he said.
"The BioBuses are part of a pioneering project to develop gas powered buses in Lincoln, which are a cleaner and greener way to travel around this city.
"Technically, it was a hugely challenging initiative and so it is extremely pleasing to see the hard work of those involved recognised in the awards shortlist."
The UK Bus Awards is a prestigious annual event celebrating excellence and good practice associated with the operation, design and promotion of bus services.
More than 270 nominations were put forward and from these a shortlist of finalists was chosen for the awards ceremony.
The event will take place at the Hilton Hotel, in Park Lane, London on November 20.
Chris Briggs, head of transportation at Lincolnshire County council, said the authority was continuing to find ways to develop attractive public transport within the county.
"We are particularly pleased that this trial is also helping us to tackle climate change, with these buses already having saved over 170 tonnes of carbon," he said.
"It is hoped that the success of this project will encourage others to explore alternatives that reduce the reliance on fossil fuels."
The BioBuses were bought with the aim of reducing carbon and exhaust emissions, improving air quality, and keeping buildings clear of traffic film.
Funding for the project was provided by the East Midlands Development Agency.
There are four other bus operators competing with Stagecoach East Midlands for the Environment Award – First Group, Reading Buses, Volvo Buses, and Stagecoach South West.
Stagecoach East Midlands runs 500 buses and carries 52 million passengers each year.