Wastewater and water treatment plants are usually the largest single electric energy consumers in each town and city.
Wastewater and water treatment processes are usually responsible for 25-40% of the total electric energy consumption in the city as it is associated with energy-consuming processes and a continuous operation cycle (24h, 365 days a year).
The changes introduced in Marselisborg / Aarhus, Denmark consisting in the replacement of conventional blowers with high-speed units brought about a 100% surplus energy production – it was achieved without adding any external organic waste or coal and with no additional investments.
Currently, the plant produces a net surplus of both electric and heat energy, supplying it to the district heating system in Denmark’s second largest city, Aarhus.
The carbon footprint was reduced by 35%.
The area of Marselisborg in Aarhus, Denmark achieved a 100% surplus energy production thanks to the consumption minimisation throughout the entire water cycle and the maximisation of energy production from the wastewater treatment plant. This was accomplished without adding any external organic waste or coal and without any new investments in renewable energy sources.
According to the report of the International Energy Agency, the water management sector today is responsible for 4% of the global energy consumption. It is estimated that this value will have been doubled by 2040. Even now there are technologies available which allow to transform the water management sector into an energy-neutral sector. Not only water management can be transformed. Electric drives are responsible for 50% of the global electric energy consumption, but they could be more efficient by as much as 40%. In the global scale, it would reduce energy consumption by 8% by 2040.
Energy independence of the water management sector according to Danfoss
see: the report “Energy Independence of the Water Management Sector”