Video: Watch: First UK 'poo bus' makes debut journey from Bath to Bristol The 40-seater "Bio-Bus" is fuelled by biomethane gas generated by the treatment of sewage and food waste at a processing plant. Colin Field of the Bath Bus Company said the new vehicle will be "quieter" and does not "smell." He said: "on a day to day basis, it will be as a normal bus...it's very hard to get people to believe in the whole recycling ethic," he said. A single tank of the gas, which is produced using the typical annual waste of five people, is enough to power the vehicle for 190 miles.