Ferrara, Italy

In the beginning

While searching for new oil fields in 1960, an underground reservoir of hot water was discovered at a depth of 2 kilometers.

After the energy crisis of the 1970s, Ferrara launched the “geothermal district heating” project based on this resource. Water at a temperature of 100–105°C was extracted from two production wells, each 1,000 meters deep. Together, they pump at a rate of 400 cubic meters per hour. The heat is transferred via heat exchangers to a secondary circuit that transports the hot water 11 kilometers to the city center.

The extracted water is reinjected into the reservoir after cooling to ensure geotechnical stability.

Expansion of the Sustainable Heating Network 

In 1990, the geothermal network became part of the "Integrated Energy District Heating Network," which combines multiple sustainable energy sources for the city’s heating needs under one framework.  

• Geothermal energy: the primary heating source  
   Energy output: 75,000 MWh per year  
   Advantages: consistent and reliable base load  
• Waste-to-Energy plant (WTE): operational since 1993  
  Energy output: 87,000 MWe (since 2008)  
  Advantages: reduces landfill waste  
• Natural methane gas boilers: seven units to handle peak demand  
  Energy output: storage capacity of 4 x 1,000 cubic meters of hot water  
  Advantages: stores excess heat and deploys it when supply exceeds demand  

The entire network spans approximately 130 kilometers and supplies energy to 530 users, including residential areas, service-sector buildings, and industrial applications.