Green Village Delft – integration of an autarkic water supply in a local sustainable energy system

For the Green Village at the campus of Delft University of Technology, an autarkic water circuit was developed. The aim was to avoid connections to the public water supply system, the sewerage, the electricity grid and cable systems. It should produce its own drinking water and electricity, and clean its organic waste streams in a sustainable way. Due to the strict Dutch drinking water regulations, only one water quality will be supplied: drinking water. Drinking water will be produced from greywater (53%) supplemented with rainwater (47%). In the treatment scheme, the multiple barrier approach will be used to comply with the Dutch drinking water quality standards. For greywater treatment, a triple barrier is suggested: ozonation – ultrafiltration – UV disinfection. For rainwater treatment a dual barrier is suggested: ultrafiltration – UV disinfection. By separating wastewater streams at the point of origin into greywater and blackwater, and by replacing conventional toilets with low water consumption vacuum systems as part of the water conservation measures, it will be possible to collect a concentrated blackwater stream suitable for recovery energy. For this purpose the upflow anaerobic sludge blanket reactor is suggested. The proposed water circuit results in an autarkic water management, but not in an autarkic energy management.