FavoriteFlows – Innovative solutions for water and energy cycles in buildings for a climate fit city

Starting point / motivation

European cities, including Vienna, are facing significant challenges due to urbanization and climate change. The increasing demand for water and the rising frequency of extreme weather events such as heavy rainfall and heatwaves are placing urban infrastructure under severe strain.

Despite growing awareness of the need for sustainable resource use, Vienna lacks concrete, scalable solutions to systematically integrate water and energy cycles, as well as greening measures, into urban planning. Particularly, the combination of water management and greening offers untapped potential to make cities more resilient and climate-friendly.

Contents and goals

FavoriteFlows develops integrated solutions for water, energy, and greening systems in large-scale residential buildings in the district of Favoriten. The project combines three key technologies: wastewater treatment through vertical green walls (vertECO®), coupled with wastewater heat recovery, and the reuse of treated wastewater for irrigation.

Additionally, innovative, flat-gradient retention roofs and infiltration systems are implemented to manage rainwater. These technologies are synergistically combined into a circular system that efficiently uses resources and improves the urban climate.

The innovation lies in the integration of improved water retention, wastewater treatment, and heat recovery, presenting an approach with the potential to optimize urban water and energy systems.

Methods

In Kempelenpark, the project demonstrates how such circular systems can be applied for the first time in large-scale residential construction and integrated into existing structures. Through collaboration with local stakeholders, city authorities, and residents, the project ensures that the developed technologies achieve high acceptance and are practically implementable.

FavoriteFlows provides a practical demonstration of how innovative water and energy solutions can enhance urban infrastructure, contribute to climate adaptation, and support the transition of our cities towards climate neutrality.

Expected results

• Efficient water use: Treated wastewater is reused for irrigation, significantly reducing drinking water consumption.
• Innovative synergies: The combination of wastewater treatment and heat recovery creates a system that enables both energy and water savings.
• Improvement of the urban climate: Green walls and retention roofs cool the city and mitigate the urban heat island effect.
• Increased climate resilience: The integration of rainwater and wastewater management systems provides flexibility in adapting to extreme weather events.
• Enhanced biodiversity: Green roofs and facades promote biodiversity, create habitats, and enhance the urban landscape.
• Reduced CO₂ footprint: These technologies contribute to lowering the city's carbon emissions.
• Model for replication: The solutions are transferable to other urban areas and serve as a blueprint for resource-efficient urban development.

Project management

alchemia-nova research and innovation gemeinnützige GmbH

Project or cooperation partners

• Heimat Österreich gemeinnützige Wohnungs- und Siedlungsgesellschaft m.b.H.
• einszueins architektur ZT GMBH
• Architekt Knötzl ZT GmbH
• Lechner + Partner Ingenieure GmbH
• rajek barosch landschaftsarchitektur

alchemia-nova research and innovation gemeinnützige GmbH
Climate Lab,
Spittelauer Lände 45
A-1090 Vienna
Tel.: +43 (650) 810 1002
E-mail: office@alchemia-nova.eu
Web: www.alchemia-nova.eu