Abstract
Within the framework of the EU Horizon 2020 project ‘ARV’, 6 demonstration sites with Climate Positive Circular Communities (CPCC) have been designed and implemented in 6 different cities in Europe, representing different climate and contexts. The demonstration projects encompass the development of a plus energy school and cultural area in a former industrial site in Oslo, Norway, energy upgrades of multi-family blocks with district heating in Sønderborg, Denmark, industrialized renovation of social housing in Utrecht, the Netherlands and in Trento, Italy, the transformation of an health care centre into a living lab for CPCC in Karvina, Czechia, and urban transformation of a city district in Palma de Mallorca, Spain. The paper describes some key lessons learned from the planning, design, construction, and operation phases of the demonstration projects, and highlight the related innovations that have been developed to make these projects viable.