City-zen was an EU-funded urban energy transition project that ran from March 2014 to November 2019. It brought together Amsterdam and Grenoble as “lighthouse” cities, with a consortium of 28 partners, to test how existing neighbourhoods could cut energy use and shift toward cleaner systems without rebuilding the city from scratch.
The project combined demonstrations, research and learning-by-doing. Its work focused on building retrofitting, smart grids, heating and cooling, monitoring, and the social and organisational barriers that slow down implementation. A notable part of the methodology was the use of “roadshows”: week-long programmes in other cities that wanted to start their own energy transition. The consortium also worked on legal and financial challenges, and on energy transition roadmaps aligned with the Paris Agreement.
City-zen’s results were reported in terms of both technical measures and urban impact. According to project summaries, it completed 20 pilot projects in Amsterdam and Grenoble, saved around 35,000 to 59,000 tonnes of CO2 per year depending on the reporting source, renovated between 76,000 and 90,000 square metres of residential buildings, and connected 10,000 dwellings to smart grids. The project also developed tools and methods intended to help cities, industries and citizens replicate these approaches elsewhere.
Key organisations included the City of Amsterdam, Grenoble-based partners, and VITO, which is listed in project contacts on the Smart Cities Marketplace. City-zen formed part of the wider European effort to make dense, existing urban areas more energy efficient through practical testing rather than pilot concepts alone.