City-ZEN Site Grenoble

Country & City: 
  • France
  • Grenoble
Contact Information: 

The city is aware of the necessity to protect its environment which participates in its own prosperity. Political actions in favor of sustainable development has been set put, emphasizing the strong political will of local authorities on this issue. As a major player in the Local Climate Plan since 2004 and as Covenant of Mayors member since 2008, the city of Grenoble is committed to reduce energy consumption, encourage the use of renewable energies, promote social solidarity, set up alternative forms of transport and develop environmental, architectural and urban quality. The main objectives of Grenoble Local Climate Plan, launched in 2004, recasted in 2009, remain to divide local greenhouse gas (GHG) emissions by factor 4 by 2050.

Between 2005 and 2012 the energy consumption in Grenoble decreased by 3.7% and GHG emissions were reduced by 17%. The final energy consumption per inhabitant in 2011 was 19.7 MWh. To go further and to turn Grenoble into a true smart city for its inhabitants, the municipality has launched the Éco-cité project in the north side of the town. This innovative concept for smart integrated city has been selected, together with 13 other advanced cities in France, to receive grant from the French Government in 2009 for the implementation of some innovative actions. Among the other inspiring cities, Grenoble takes the first place because Eco-cité project is gathering private and public stakeholders around demonstrations projects for which political decisions have already been taken in the fields of mobility, building and energy.

The overall objective of the City-ZEN project is to transform the Éco-cité area into a positive energy and carbon neutral district.

Retrofitting private co-owned buildings and social housing

The city will focus on the existing dwellings of the Eco-cité area with the objective to reach the level of current thermal regulation for new buildings. Private co-owned multi-family buildings are the main challenge for 2020 objectives. The city will develop a retrofitting intervention strategy based on buildings technical and architectural typologies as well as on the social and economic conditions of the families. In Grenoble, 500 dwellings will be retrofitted, leading to a saving of 9,600 tonnes of CO2 per year.

Creating a low temperature heating and cooling network

The new buildings of the area will be energy efficient. The CO2 reduction target is 1,300 tonnes per year. The objectives of the innovative thermal loop are :

  • adapt the heat of the grid to this new energy efficient building’s needs, by designing a very low temperature district heating loop in order to avoid heat losses compared with the traditional Grenoble’s district heating
  • improve the overall district energy efficiency by connecting his loop to a heat recovery system form sewage water coupled with heat pumps
  • demonstrate seasonal storage solutions with dry geothermal boreholes

Saving and monitoring energy flows

The objective is to monitor and manage all the energy and water flows in order to save energy and assess systems and policies efficiency with a multi-energy territorial monitoring system :

  • implement innovative solutions to optimize the electric system
  • demonstrate a smart management of various energy flows, providing an optimized and rational use of local resources
  • demonstrate a multi utilities vision, though building an innovative multi-energy real-time territorial monitoring system, with an user-friendly approach for citizens