The power of poo

Posted 7 August 2017

Poo powered carQueensland Urban Utilities (QUU) has unveiled Australia’s first poo-powered car. 

Well, it doesn’t technically run on poo. But it is powered by electricity generated from human waste, said QUU spokesperson Michelle Cull. 

“We’re converting the waste from 300,000 people into electricity to run both the electric car and our sewage treatment plant,” Cull said. 

The utility has three cogeneration units operating at two of its sewage treatment plants: Oxley Creek and Luggage Point. This poo-powered car, a Mitsubishi innovative Electric Vehicle (i-MiEV), uses electricity generated from biogas from human waste at the Oxley Creek treatment plant. 

“This is an example of how modern sewage treatment plants are becoming more like resource recovery centres, where we’re turning waste into something useful like energy,” Cull said. 

QUU’s cogeneration units currently satisfy 50% of the plant’s energy needs, saving $2.5 million per year. Beyond that, the units are also an important step towards the utility achieving zero-emissions. 

“The poo car is not only keeping our costs down, but it’s a cleaner, greener source of energy; it doesn’t produce any emissions – it doesn’t even have an exhaust pipe.” 

Besides the potential to “power our whole fleet on poo power,” Cull said QUU is investigating ways to use the biogas as a standalone product to power a car, cutting out the need to generate electricity from it. 

However, one hurdle to overcome is the question of purifying biogas. Most biogas produced from sewage is 60% pure, but to run a vehicle it needs to be about 95% pure.

“We would need the technology to scrub the biogas and clean it to that standard, which would require significant investment,” Cull said.

“With the cogeneration equipment we already have, it made sense to go the path of electricity first. But in the future, we might also be able to run cars on biogas generated from sewage.”

QUU is also using the poo-powered car to start a conversation with the communities it serves about renewable energy and turning waste into a useful product – and of course indulge in a little toilet humour.

“We liked the idea of the poo-powered car because it’s a great way for us to communicate with the community about the things we’re doing with their waste,” Cull said. 

“We have fielded questions about everything from how it smells to whether it leaves skid marks, but so far we’ve had a great reaction and it’s definitely turning heads on the street.”