In Barcelona, Certain Buses Run On Biomethane Produced From Human Waste

From the French newspaper Le Monde:

Odorless, quiet, sustainable. On the last day of July, passengers boarded Barcelona's V3 bus line with no idea where its fuel came from. Written in large letters on the bus facade, just below its name 'Nimbus,' a sign clearly stated: 'This bus runs on biomethane produced from eco-factory sludge.' Still, the explanation was likely too vague for most to grasp its full meaning. The moist matter from wastewater treated at the Baix Llobregat treatment plant was used to produce the biomethane. In other words: the human waste of more than 1.5 million residents of the Catalan city.

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