As of today, Britain’s first “poo bus” will be shuttling passengers between the city of Bath and Bristol Airport. And yes, you guessed it: it’s powered by human waste, alongside food waste.
This “Bio-bus” runs on biomethane gas, which is produced from the treatment of human sewage and food that is unsuitable for human consumption. It has a combustion engine that is similar to diesel engines in normal buses, but the gas is stored in dome-like tanks on the roof.
The gas is generated using anaerobic (oxygen hating) bacteria, which break down the waste into methane-rich gas. Before it can be used to power buses, CO2 is removed and propane is added. Other impurities are also removed so that the emissions are virtually odorless (thank goodness). It also produces fewer overall emissions than traditional diesel engines, and is obviously more sustainable.