Barcelona’s public transport operator TMB is exploring ways of running the city’s buses on sewage sludge-derived biomethane.
Biogas from the city’ wastewater treatment facilities is made up of methane and carbon dioxide and the aim is to remove the carbon dioxide leaving biomethane, which can be compressed to create fuel for the city’s buses.
Currently, just one bus is being tested, but there are plans to have 46 methane-fuelled buses on the streets by 2024.
The initiative is part of the EU funded Nimbus Project, set up to encourage a circular economy within public transport.
Although TMB has been converting its fleet to lower emission vehicles over the last decade, it’s still far off the EU’s commitment for over 30 percent of energy consumption for transport to be from renewable sources by 2030.
Biogas generated at the city’s water treatment works which is currently stored and used later to power the plant. From March, the carbon dioxide will be removed and the remaining biomethane compressed to make fuel for the Barcelona buses.
“This is about using bioproducts, which already exist in the atmosphere and giving them a new life,” said TMB depot supervisor Angel Olmo.