CoolCity lake water network, an urban powerhouse
An innovative project for sustainable energy supply, CoolCity, is being developed in the center of Zurich. By combining heating and cooling technologies, a pioneering step is being taken towards ecological urban development.
As temperatures rise, Zurich is seeing an increase in the use of air conditioning systems, which significantly increases the city’s energy requirements. CoolCity is responding to this trend with an ambitious concept designed to sustainably cover the energy requirements for heating and cooling.
A strategically positioned energy centre
A 4,000 m² energy centre is being built in the heart of Zurich, in the ewz Selnau substation. This serves as a central interface for the efficient distribution of heating and cooling and is a key element of the city’s energy supply network. The project guarantees an optimum temperature supply for its users: 67°C for heating and around 12°C for cooling, directly from the lake water. Temperatures adjusted on site by heat pumps and cooling systems ensure maximum efficiency and comfort.
A sustainable energy distribution system
At the heart of CoolCity is a sophisticated system of primary and secondary circuits. This structure enables the flexible provision of heating or cooling and is supplemented by energy-saving freecooling in summer. It is not only a project for the present, but also a forward-looking step towards Zurich’s goal of achieving net-zero emissions by 2040. The use of deep water from Lake Zurich to heat and cool buildings reduces CO² emissions by an average of 80 per cent compared to fossil fuels.
Overcoming challenges
Despite widespread approval, ecological, legal and technical challenges must be overcome during realisation. Close collaboration between the experts at ewz, Anex and other stakeholders is essential in order to develop innovative solutions for civil engineering and the continuous energy supply.
CoolCity is scheduled to go into operation in stages from 2031. This will allow the system to be adaptively optimised to meet Zurich’s changing needs. Through this development, Lake Zurich will take on a dual function: in addition to a local recreation area, it will become the basis for a sustainable energy supply for the city.
CoolCity symbolises Zurich’s pioneering spirit and its efforts to create innovative solutions for a sustainable future. Through the intelligent utilisation of lake water for the city’s energy supply, the project sets new standards in ecological urban development.