It takes just over three weeks: flush a toilet in Didcot, England and 23 days later, it has produced biomethane that heats about 200 homes—through the national grid.
The BBC explains how the project goes beyond existing waste-to-energy facilities:
The practice of using anaerobic digesters - carefully managed bacteria - to turn faeces into a means of generating electricity is already well established across the country. But the additional plant that British Gas has installed at the Thames Water sewage treatment works in Didcot cleans up the spare biogas that is produced and turns it into biomethane suitable for household hobs and in gas central heating.
The project is a joint effort by British Gas, Thames Water and Scotia Gas Networks, which collectively hope to replicate the process across the UK.Expanding beyond Didcot
British Gas already has four other biogas-to-grid projects planned, but it's not the only company going down this path.
Projects that feed biogas into the grid are not new, and even exist in the U.S., but this is thought to be the first time people are using their own human waste to power homes through the natural gas grid.
United Utilities and Ecotricity also have plans in the works to feed biomethane into the grid, and if the company's estimate is accurage, United Utilities could by powering 500 homes this way as soon as next summer.
NewNet quotes an official from Thames Water: "For decades we've generated electricity by burning sewage sludge or methane derived from it, saving £15m in power bills last year alone."
Using biomethane from sewage as another source of gas was just the next step on their "renewable energy hit list."