Water authorities in the Netherlands no longer regard wastewater as merely a by-product to be treated and processed, but as a valuable source of renewable energy, raw materials, and clean water. This approach is appropriate to the wider societal transition to a circular economy. In order to contribute to this transition, the water boards have set up a collaborative network organization called Energy and Resources Factory (Energie- en Grondstoffenfabriek).
Valuable raw materials
The wastewater treatment process yields energy, which can be converted into biogas to power cars or electricity to be supplied to households – true ‘green electricity’ from your local water authority. The raw materials that can be recovered from wastewater include phosphate, which is used to produce fertilizers among other things.
The 21 Dutch water authorities have joined forces with Dutch Water Authorities (the umbrella organization of water authorities in the Netherlands), the Foundation for Applied Water Research (STOWA), a number of knowledge institutes including Delft University of Technology, the Netherlands Green Gas Foundation, the Netherlands Nutrient Platform, and many other organizations.
Eight sewage treatment plants have already been transformed into Energy Factories, with preparations underway for a further nine factories. Of course we are also very proud of the green electricity that we produce. Intensive research is being conducted into the recovery of valuable raw materials like alginate and cellulose from wastewater. In addition, phosphate is already being recovered at seven sites.