In Milanxxvi xxvii, developing and expanding the district heating network does not require as much a municipality-led infrastructure overhaul as it does cooperation from private building owners. This is because many buildings in Milan already have a building-wide central heating system, only requiring substitution of the existing boiler by a heat exchanger and connection to the network. This shift is directly cost-effective and has a short payback time (4-5 years) if replacing a diesel boiler. Previously, regional subsidies supported the switch from diesel oil to district heating, but thanks to decreasing prices of new technologies and stable or higher fuel prices, the switch is now cost-effective enough and is also generally offered by energy suppliers through energy service contracts. However, communication and awareness-raising of district energy and its benefits are key for building customer trust in these energy suppliers and obtaining the energy service agreements.


Milan promotes the district energy and energy efficiency retrofits through its Energy Help Desks that are run by the municipality as an information service to current and potential customers. Energy experts are available in city districts’ offices and help address any questions about potential energy service interventions, as well as available incentives and financing options for district heating, renewable energy and energy efficiency. In addition, a central office uses public information campaigns to counter the image of district heating as an inefficient and outdated technology and instead promotes it as a critical modern energy system for reducing carbon emissions and reaping other environmental benefits. To date, around 150,000 apartments in Milan are connected to the district heating network, with 150,000 expected to be connected in 2020xxviii.

Reasons for success

The success of Milan’s awareness-raising approach is driven by a strong partnership with the energy utility and energy service providers, providing customers an “offer you cannot refuse”. The help desks provide concrete information and responses to practical and technical questions, helping build trust in district heating and the retrofit/connection process.

When/why a city might apply an approach like this

Cities with limited experience with district energy – or with a legacy system that has a poor track record – should consider proactively educating stakeholders about district energy and its benefits before, during and after project development. By engaging developers and individual customers through information campaigns and awareness-raising efforts, the city and its utility partners can build their confidence in service providers and facilitate network connections. 

C40 Good Practice Guides

C40's Good Practice Guides offer mayors and urban policymakers roadmaps for tackling climate change, reducing climate risk and encouraging sustainable urban development. With 100 case studies taken from cities of every size, geography and stage of development around the world, the Good Practice Guides provide tangible examples of climate solutions that other cities can learn from. 

The District Energy Good Practice Guide is available for download here. The full collection of C40 Good Practice Guides is available for download here.  

All references can be found in the full guide.

  • Economic
Key Impact
300,000 apartments connected to district heating network by 2020
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