District heating (DH) systems are one of the most energy efficient heating systems in urban environments, with proven reliability within many decades already. DHs have traditionally been designed to be operated in a hierarchized way, with central energy production facilities delivering heat to a variety of distributed consumption locations. DHs are identified as key systems to achieve the de-carbonization of heating energy in European Cities. Renewable and waste heat sources are foreseen at the same time as de-carbonized heat sources and the way to guarantee competitive energy costs with limited influence of fossil fuel supply price volatility. To achieve this, conversion of DHs is needed regarding: - The reduction of their operation temperature to avoid current technical constraints in the integration of low-grade industrial heat sources, - The introduction of larger shares of renewable energy sources (RES) in the DH network. - The introduction of distributed heat sources (reject heat from cooling equipment...). - To guarantee economic viability with the trend of DH heat load reduction due to the evolution of the building stock toward NZEB (Near Zero Energy Buildings). RELaTED will provide an innovative concept of decentralized Ultra-Low Temperature (ULT) DH networks, which allow for the incorporation of low-grade heat sources with minimal constraints. Also, ULT DH reduce operational costs due to fewer heat losses, better energy performance of heat generation plants and extensive use of de-carbonized energy sources at low marginal costs. The RELaTED ULT DH concept will be demonstrated in four complementary operation environments (new and existing DH, locations, climatic conditions, dimension…) in Denmark, Estonia, Serbia and Spain. RELaTED approach will follow the strategy of the electrical smart grids, in which energy generation is decentralized and consumers evolve to prosumers (they consume and produce energy).

The aim of the oPEN Lab is to identify replicable, commercially viable solution packages enabling the achievement of positive energy neighbourhoods within existing urban contexts that are seamlessly integrated into the local energy system as an active micro-energy hub, and to test these technologies and package as an integrated solution at neighbourhood scale. Three open innovation living labs in the cities of Genk (BE), Pamplona (ES) and Tartu (EE) will test combinations of different close-to-market ready technologies and services and study their performance as a unique operating system. Focus is on demonstrating innovations in an integrated approach combining sustainable design tailored to the local context, seamless industrial renovation workflows, renewable energy generation combined with energy storage systems, urban service facilities and smart operation, life cycle thinking and circularity, and this across the whole value chain, targeting the whole life cycle of the building and its neighbourhood, in view of scaling up and wide replication. A user driven and participatory approach with the neighbourhood?s community will be rolled out for a holistic and positive energy vision for the neighbourhood, going beyond citizen awareness raising activities. oPEN Lab is a unique collaboration aligned with the Open Innovation quadruple helix model where a) industry (SMEs, large companies, start-ups and scale-ups in both construction and energy value chains), b) government (local public administration), c) academia/RTOs and d) civil participants (end users, NGOs) work together to co-create and drive structural changes that will result in high TRL levels, with great focus on exploitation of results and wide replication.

SmartEnCity’s main Objective is to develop a highly adaptable and replicable systemic approach towards urban transformation into sustainable, smart and resource-efficient urban environments in Europe through the integrated planning and implementation of measures aimed at improving energy efficiency in main consuming sectors in cities, while increasing their supply of renewable energy, and demonstrate its benefits. The underlying concept of the proposal is the Smart Zero Carbon City concept, where city carbon footprint and energy demand are kept to a minimum through the use of demand control technologies that save energy and promote raised awareness; energy supply is entirely renewable and clean; and local energy resources are intelligently managed by aware citizens, as well as coordinated public and private stakeholders. This approach will be firstly defined in detail, laid out and implemented in the three Lighthouse demonstrators (Vitoria-Gasteiz in Spain, Tartu in Estonia and Sonderborg in Denmark). The three cities will develop a number of coordinated actions aimed at: • Significant demand reduction of the existing residential building stock through cost-effective low energy retrofitting actions at district scale. • Increase in RES share of energy supply, through extensive leveraging of local potentials. • Enhance the use of clean energy in urban mobility, both for citizens and goods, by means of extensive deployment of green vehicles and infrastructure. An extensive use of ICTs is planned to achieve integration and consistency in demo planning and implementation, and to enable further benefits and secure involvement of citizens. These actions will be aligned to city-specific Integrated Urban Plans (IUPs), and the process will be replicated in two Follower cities: Lecce, (Italy), and Asenovgrad (Bulgaria) to ensure adaptability and maximize the project impact. Additionally, a Smart Cities Network will be setup to support project replication at European scale.