Fredericia Wastewater and Energy Ltd. operates the second largest wastewater plant in Denmark, as well as 1000 km sewers and more than 100 pumping stations and water basins. Each year 10 mill. m³ of waste water are transported and treated. Up to 70% of the waste water is industrial coming from e.g. dairies, a brewery and an oil refinery. After mechanical and biological treatment, the treated water is pumped into Lillebælt, while the sludge is sanitised, used for biogas and finally as fertilizer in agriculture. The biogas is used for production of green electricity, heat and natural gas.