Are these cool(ed) Viennese benches the street furniture of the future?

The city’s district cooling network gets creative and shows that every part of the process can be utilized

Wien Energie, the largest energy and district heating and cooling supplier in Austria, has unveiled new intriguing cooling street furniture at the forecourt of the Spittelau waste incineration plant. These unusual benches let sitters experience a cooling effect in the summer heat and demonstrate the capacity of the city’s district cooling network.

The best thing about the cooled benches is that they don’t require any additional investment to make them “work”. They are cooled by water that returns to the plant through pipes after having cooled buildings. Even though the returning water is warmer than the outgoing water headed to the buildings, at 15-20 degrees Celsius it is still cooler than the summer air without feeling freezing.

The returning district cooling is recycled and reused, so to speak," explains Michael Strebl, Chairman of the Wien Energie Management Board.

This means that the benches provide a rather pleasant experience for sitters who want to have a break and test them out. They could also be a potential solution in the provision of reprieve from the urban heat islands effect that major cities suffer from in summer.

Experience district cooling in the outdoor public space

The “Kühlruhe” furniture, designed by Bergnerdesign, is made from concrete produced regionally in Lower Austria. Concrete is particularly suitable for storing and slowly releasing cold, which is why the design team chose this material.

If you’re wondering how district cooling itself operates – here’s how.

Cold water gets generated in the incineration plants using highly efficient refrigeration machines. In addition to electricity, excess heat from waste incineration is also used as the driving energy. The water, cooled to around 5-6 degrees Celsius, is delivered directly to customers via the district cooling network and is then distributed in the buildings via the company's own cooling systems.

The water absorbs the heat from the building on site and transports it away. Recooling is also carried out centrally, for example using river water. This is also good for the environment: compared to conventional air conditioning systems, district cooling saves around 50 per cent CO2. Plus, it is powered by electricity that comes 100% from renewable sources.