This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
Humans produce around 360 pounds of poo over the course of a year – and the United Kingdom’s “Bio Bus” is taking this poo on the road.
This 40-seater, single-decker bus now runs the 20-mile stretch between Bath and Bristol Airport in southwest England. Dubbed the “Poo Bus” or “The Number Two” by many in the UK, the bus uses biomethane for its fuel.
This biomethane is made using human excrement and food waste that has been converted via a process called anaerobic digestion in a nearby treatment facility. In this process, microorganisms break down organic materials (for example, food scraps, poo, and animal manure) in the absence of oxygen, producing a biogas and a solid compost-like material.
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Anaerobic digestion is used around the world, turning waste streams into usable fuels. In the United States, East Bay Municipal Utility District in Oakland, California became the first wastewater treatment plant in the nation to convert food waste to usable biogas via this process. In Norway, the city of Oslo dove into the Poo-to-Pump concept in 2009, converting 80 buses to run on biomethane as part of its plan to become carbon-neutral by 2050.
With a driving range of 186 miles, the United Kingdom’s Poo Bus uses the equivalent of the biomethane produced by 5 people’s “sewage” and food waste between fill-ups.
Put another way, assuming that the Poo Bus runs 10 round-trip journeys per day it will burn through the equivalent of 3,950 people’s waste over the course of a year.
Photo Credit: Photo of Bio Bus by Wessex Water (via YouTube).