Modern sewage facilities need huge amounts of energy to turn your dirty business into clean water. In conventional sewage plants it goes a little something like this: micro-organisms digest solid waste (your poo and other stuff you flush down the toilet) in 'activated sludge'. These bacteria convert all organic materials to methane but need fresh oxygen for it and leave waste containing ammonium and phosphates. To provide the bacteria with oxygen and to get rid of this ammonium sewage plants need energy. Lots of it.

Thanks to my fellow Dutchman Gijs Kuenen and the TU Delft this energy waste could be drasticly reduced in the near future. Gijs and his team discovered a new kind of bacteria that can break down ammonium without the need of oxygen. And no oxygen means no energy wasting oxygen pumps and installations.

This month the team will begin building a pilot plant to demonstrate the technology at the Dokhaven waste water treatment plant in Rotterdam, the Netherlands, working with from Radboud University Nijmegen and water purification firm Paques, based in the Dutch town of Balk.