The term energy self-sufficient is used in connection with wastewater treatment plants, which on annual average produce at least as much energy as they consume. The focus here lies on the average annual energy requirement and does not generally prohibit energy intake.
Self-sufficient wastewater treatment plants are plants that cover their energy requirements with only the energy contained within the wastewater. In practical terms, this means that sludge digestion is absolutely necessary for the production of biogas (fuel) as their source of energy.
On the other hand, energy-autonomous wastewater treatment plants that employ the help of renewable energies, are plants that cover at least part of their energy needs through photovoltaics, wind energy, or possibly also through co-fermentation of external biomass.


« back