considerably reduce the energy consumption in the processes. Two of our treatment plants have side 
stream de-ammonification installed.  

All throughout process optimization projects that we have done during the course of a number of years, 
there has been a special focus on reduction of electricity consumption, chemical and resource usage. 
This was done in partnership with an external consulting company.  

Performance Measures & Results 



Reduction of electric energy usage between 2010 – 2015 -  4,831,061 KWh / 20 % reduktion    



CO2-reduction 2010 – 2015 - 3,078 tons CO2 / 26 % reduktion  



Specifik Energy konsumption  - 2010: 0,68 kwh/m3 2015:0,5 kwh/m3, Reduction 2010-2015: 



Annual investments in energy initiatives During the period 2010 – 2015, an average of USD 1.4 
million was invested annually in projects leading to increased energy production.  



Overall degree of energy self sufficiency - Went from 14% in 2010 to 42% in 2015  




Indication of management commitment (e.g., standard operating procedures; board/executive 
management renewable energy conversion policy, including quantitative goals developed and 
shared with stakeholders)   


Internal energy sources evaluated (e.g., biogas, hydropower, heat in wastewater), and/or 
renewable energy sources evaluated on an ongoing basis (e.g., solar, wind, co-digestion)  


Recovery of digester gas in a combined heat and power (CHP) system, and boilers in place (for 
process and building heating)   


Conversion of digester biogas to electricity and heat, and/or transportation fuel Yes   


Solar panels, wind turbines, heat recovery, in conduit hydro, and/or hydroelectric power 
generation systems installed  

Marselisborg treatment plant has achieved a total energy production of >200% degree of self-
sufficiency. This was accomplished by utilizing a CHP system and thereby producing approx. 135% el. 
energy and 65% heat energy – both exported to the public net.  

In 2015-16, new primary filters, digesters and a CHP system were installed at Egå treatment plant with 
the goal of being 150% self-sufficient with el. energy. To accomplish this, de-ammonification is 
implemented on the biology to further increase the degree of self-sufficiency.  

Egå WWTP is also working on converting excess heat to produce el. energy which is done by converting 
thermal energy via a small turbine.   

In 2016, an area outside the Egå WWTP was set aside for the planting of willow. The crop is fertilized 
with nitrogen via reject water from the treatment plant’s final dewatering. This secures savings at the 
treatment plant in relation to aeration; but also results in considerable CO2 savings, as the crop binds 
important amounts of CO2. 

Performance Measures & Results