With a water-filled rock chamber beneath Kungsholmen in Stockholm, the energy company Fortum has been able to substantially increase capacity in the city’s network for district cooling. The ordinary cooling plants can be phased out, and both high electricity needs and the risk of leakage of ozone-depleting substances will disappear along with them.

Positive environmental and economic impacts

• At full capacity, electricity consumption can be reduced by 45 GWh per year.

• Cooling machines with a combined output of more than 80 kW can be switched off.

• Reduction in greenhouse gas emissions of 5,000 tonnes of CO2 per year.

• No leakage of ozone-depleting refrigerants.

• Reduced noise when cooling plants are removed.