Energy efficiency

In line with Swiss Prime Site's sustainability strategy, the Prime Tower Site is designed for energy efficiency. A large part of the general electricity demand is covered by solar energy.

The site has a district heating and cooling storage system and consists of a sophisticated, state-of-the-art and complex system to achieve the best possible energy efficiency. The high standard of building materials, the photovoltaic system, the quality of indoor air and many other measures increase the sustainability and comfort on site. In order to increase energy efficiency in the Prime Tower Site, various measures are being taken: part of the electricity is produced by the photovoltaic system on the roof, heating is provided by waste heat from the city of Zurich and the natural ventilation process ensures a fresh indoor climate all year round

Photovoltaic system on the «Platform» building

The photovoltaic system of the Prime Tower Site is located on the building «Platform« and produces approximately 130,000 kWh per year. The electricity produced could be used to cover 5.1 million kilometers on an e-scooter, for example. Finally, about 15'000 liters of heating oil can be saved annually. This corresponds to the average annual consumption of approximately five four-person households in Switzerland.

Heat pump for domestic hot water

At the Prime Tower Site, groundwater is used as a meaningful and renewable energy source for operating the heat pump. Groundwater is considered one of the most effective energy sources for heat pumps since groundwater water temperatures remain at 11 to 13 °C on cold days, allowing efficient heat generation even in winter.

Use of waste heat for heating

Significant advantages can be achieved by recovering heat from the refrigeration system. Not only is the energy that would otherwise be lost made usable again, but it also allows for complete elimination of fossil fuels. This results in a significant reduction in CO2 emissions. The newly obtained energy is used to operate the heating system.

District heating from the city of Zurich as a supplement

If the sources of energy mentioned earlier are insufficient, the district heating network of the city is used as a supplement. This involves utilizing waste heat from waste incineration or energy from lake and river water. This approach helps to proactively prevent resource losses.

Cold storage

The cold storage facility at the Prime Tower Site offers many advantages for the sustainable use of existing energy. The generation of cold and the demand for cold can be separated in time using this system, which increases energy efficiency. In addition, this allows for better synchronization of the electricity consumption for the refrigeration machines with the availability in the Swiss power grid.

Natural ventilation

The Prime Tower's building technology features natural ventilation, which is supported by intelligent automation of the 1381 windows. The windows open only when appropriate and beneficial to improve the indoor climate, thanks to sensors and time control. The ventilation process takes place through exhaust ducts in the exterior walls ensuring a fresh indoor climate all year-round while reducing CO2 emissions.

Mobility and synergies

The Prime Tower Site is located centrally in Zurich's vibrant District 5 and is a popular place for meeting and interaction. Short distances and the best connections are guaranteed.


The Prime Tower has received several awards as a sustainable building: it meets the Minergie standard and has been awarded LEED Gold status.