Believe it or not, we once worked out – as best we could – how much energy you could generate if you burned the poop of our planet's entire human population. It’s surprisingly little, perhaps enough to power a few million standard American households.
Saying that, poop can be used as a (flawed) power source when push comes to shove, and as highlighted by a piece in The Guardian, there is a place on this curious planet where dog poo can electrify a street lamp. This isn’t a new revelation: shit-powered showcases of this technology date back to at least 2010, with glorious reports in Popular Science and Grist also explaining the science behind this stinky innovation.
So what’s the story? A few years back, Park Spark appeared in Massachusetts. Dog waste is dumped into a “digester”, where bacteria break it down anaerobically – without using oxygen. The excretory mixture is then sloshed around a bit to allow the all-important byproduct, methane, to shift upward, where it is ignited in order to produce thermal energy, which is converted to electricity for the street lamp.
The Guardian now explains that there’s an equivalent in the UK too. An inventor, tired of finding poop-containing bags hiding in the shrubbery near his home, has engineered his own version of Park Spark. Successfully lighting up both the street and people’s collective imaginations, 10 bags of dog doo-doo can now power a light for two hours.
The hope, in the cases of both projects, is that their poop power will proliferate across the country into other streets and parks. Sure, it won’t revolutionize the way we get energy – that’s really down to wind, solar, and perhaps nuclear for the time being – but it is rather lovely to see literal waste being put to good use. There’s less mess on the floor, and marginally less electricity off the grid is required to shine a light.
Using various forms of biological waste to power things on a local scale is far from new. In developed countries, like the UK, it’s an exciting avenue of electricity generation. Just look at the unbridled enthusiasm on Yorkshire Water’s “Poo Power” website, which exclaims that “the poo of 100,000 people can generate 51 kilowatts of electricity, enough for 500 light bulbs.”