Overview: Rijeka is Croatia’s third-largest city, and also an economic hub, hosting Croatia’s largest port. Reflection of its relevance is its district heating network, one of the largest in Croatia. As the city grows, the plans to expand and improve the network need to follow along.

Current DH System: The heat for the DH system in Rijeka is generated at 14 separate DH plants located all around the city. Currently, approximately 17km of pipelines supply heat to 9400 households and 150 commercial users. The total installed power is 86,3 MW while the peak load is around 35-40 MW. The DH system uses 33 separate units (23 natural gas boilers, 3 fuel oil back-up boilers and 7 CHP units) for the heat generation. The system provides heating and domestic hot water. In 2024, the system generated 79,5 GWh of energy (62,5 GWh of heat and 17,0 GWh of electricity), primarily using natural gas

What work will ENABLE DHC do?: One of the project objectives is to end Rijeka’s dependence on fossil fuels for heat generation. Today, 90% of the heat in the city’s district heating comes from natural gas. The project will investigate the use of waste heat from sewage water and large-scale solar fields to substitute for fossils. This will be coupled with heat storage tanks and retrofitting of the grid, increasing efficiency.

Partners involved: Ambiente Italia and Energo