ΝH3END aims to develop an innovative method of enriching and preserving mixed methanogenic populations in anaerobic bioreactors capable of fully respond to the current levels of NH3 concentrations that biogas plants in Greece operate. In addition, in order to improve the environmental footprint of biogas plants, NH3END will develop a combined modified process where the dissolved NH3 in the effluent fluids will be recovered in the form of biomass (algae) contributing this way to the reduction of nitrogen, but also phosphorus in the treated substrates. Furthermore, NH3END will enhance the automated operation of biogas plants by developing a predictive controller that will control the operational parameters of the bioreactor by optimizing the process. The combination of innovative actions to be developed within NH3END will lead to a 30% increase of methane production.