Oslo – Forget hybrids and electric motors – buses in the Norwegian capital are set to use sewage as fuel, as part of the city’s attempt to be carbon neutral by 2050. Eighty municipal buses will be equipped with the necessary engine conversions in order to run off biomethane extracted from Oslo’s sewage output. The buses will begin running in September this year; if the project proves successful, the city’s entire fleet of buses will eventually be converted as well.