The beauty of algae ponds is that they can be added to the existing technological process without changing the original system. Their biomass can be used for additional value streams, while the treated wastewater usually complies with the demands for environmental release. In the case of biogas plants, algae can be used for stabilisation of liquid anaerobic digestate, which is problematic to manage because it is very dilute. Algal systems enable concentration of nutrients and organic matter into biomass, while treated water can be utilised for irrigation. Algae also recycle CO2, effectively use excess heat, and reduce the odour of digestate. In sewage treatment plants, algal systems can replace secondary and tertiary water treatment, and instead of sludge, valuable biomass is produced.
Algae ponds are easily operated and can fit nicely into the rural landscape.