AR-HES-B – Energy storage, production and recovery of valuable substances in wastewater treatment plants

AR-HES-B develops technologically based concepts of municipal wastewater treatment plants in order to convert them from energy consumers into a hybrid energy provider, energy storage and a provider of resources. The concept enables wastewater plants to turn into an important platform in the regional energy and mass transfer.

Short Description




Starting point / motivation

The urban sewage treatment nowadays is a classical end-of-the pipe system. The conventional municipal biological-aerobic wastewater treatment is an energy intensive process. Vast amounts of potential energy (bound in carbon) and valuable nutrients (e.g. nitrogen) are destroyed in the energy intensive aerobic aeration.

The wastewater treatment plants (WWTP) are the major energy consumer in Austrian municipalities. Prospective, the consumed energy in urban agglomerations will be still produced only to a little extent within the city boundaries.

Besides the fluctuating energy quotation due to volatile, renewable energy resources (e.g. infrequently resp. periodically available wind power and above all solar power/ photovoltaic) the decentralised, fluctuating part in the public power grid increases.

Contents and goals

The overall project goal of the AR-HES-B project is the technology rearrangement of the municipal wastewater treatment plant in order to transform the municipal wastewater treatment plant from a high energy consumer towards an optimal integrated hybrid energy provider, energy storage and resource provider in the urban environment.

Via the AR-HES-B concept the municipal sewage treatment turns into an important platform in the regional energy and mass transfer. The wastewater treatment plant as a hybrid energy provider, energy storage and resource provider will be the intelligent alliance of wastewater-, electricity-, gas- and district heating grids right at the interface WWTP. Thereby storage peak loads can buffered by integrated sustainable solutions for in the district heating and power grids.

The aim of the wastewater treatment is not only in utilization of the bound energy, but the utilization of all the valuable substances contained in the wastewater up to the usage of the cleaned water itself. Beyond that, the required organisational framework conditions and the acceptance of the involved key players are clarified.


The technological options will be defined in collaboration with experts via an Excel-based calculation-tool. Other tools used are the PNS – Process Network Synthesis for the selection of the optimal technological option. The decision support tool will be evaluated against three case studies. In addition there will be an ongoing involvement of relevant stakeholders in order to increase the acceptance and to support the business modelling.

Expected results

The outcome of the project is going to be a detailed guideline “Future Wastewater Treatment Plant”, which contains all topics addressed in this project. The guideline serves as a catalogue of suggestions of the implementation and the evaluation of concrete measures.

Additionally, detailed “technology-variations” are developed as a foundation for the AR-HES-B concept. The AR-HES-B concept are adjusted and optimised for wastewater treatment plants by the uptake of the specific demand profiles of local energy provider grids in combination with technology-variations. Thereby a very powerful optimisation tool is available.

Within the project a realisation concept will be developed by conducting three case studies at three wastewater treatment sites to show the potential and the impact of the AR-HESB concept.

Project Partners

Project management

Ao. Univ.-Prof. DI Dr. Hans Schnitzer, StadtLABOR Graz

Project or cooperation partners

  • AEE – Institut für nachhaltige Technologien

  • Abwasserverband Gleisdorfer Becken

  • Stadtwerke Gleisdorf GmbH

  • Feistritzwerke STEWEAG GmbH

  • Nowak AbwasserBeratung

  • EnviCare Engineering GmbH

Contact Address

Ao. Univ.-Prof. DI Dr. Hans Schnitzer
Reininghausstraße 11a
A-8020 Graz
Tel.: +43 (316) 22 89 46