Passengers have had a sneak preview of the bus of the future in Swansea.
The Electocity Hybrid bus is being tested in Swansea
First Cymru has been conducting the first Welsh trials of an electric bus that produces just a twentieth of the harmful emissions of normal buses.
The Electocity Hybrid bus has found some of the city's steeper hills a bit of a challenge but it could be running on the flatter routes by 2006.
Passengers who climbed on board this week gave it the thumbs-up and said they would like to see more introduced as soon as possible.
Christine Brown said: "It's a very good idea.
Christine Brown was impressed by the clean air on board
"It's a nice airy bus and there are no smells like the other buses, which I guess is because of the emissions.
"It's also a lot quieter but other than that you would not notice the difference from other buses."
Fellow passenger Alex Combe said: "It's obviously a smoother ride because you've not got the petrol or diesel engine.
"It's first class for the city and the environment."
Student Mike Hoskins was also full of praise.
He said: "I think it's a really good idea, especially for helping the environment.
Mike Hoskins thinks it is a good idea for helping the environment
"It's just like a normal bus but maybe quieter."
The prototype seen on Swansea's roads this week is made by The Wright Group which aims to go into full production next year.
Managing director Maurice Perl explained the hybrid electric engine incorporates a gas turbine generator and batteries.
"If clean buses can be produced we are going to encourage more people to take the bus," he said.
"This bus is twenty times cleaner than a normal bus and as near to zero emissions as you are going to get.
"There are something over 120 air quality areas in the UK - what that means is the air quality is not good enough to pass EU standards being introduced in 2005."
One of these is the Hafod area of Swansea, he said.
"If there are clean buses around the chances are councils are going to be looking at banning cars and other vehicles in certain parts of city centres."
Mr Perl said drivers also felt it was less stressful behind the drive.
Driver Steve Bodley described the bus as a 'nice drive'
Steve Bodley, who has been behind the wheel for most of the week, agreed.
"It takes a bit of getting use to but it's not that different," he said.
"It's a littler slow on the hills but it is a lot quieter - it's a nice drive."
First Cymru Managing Director Justin Davies said the buses may be on the streets in Swansea full-time from 2006 or 2007.
"People are more aware of the environment these days and I think people will only become more concerned about what's being pumped into the environment in the future," he said.
"Twenty or even 10 years you would not have thought we would all go down to the recycling plant every Saturday morning with our bottles and cans.
"Using clean buses and cars may well be another environmental choice people make in the future."