From nearly-zero energy buildings to net-zero energy districts

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JRC Report - Residential and tertiary buildings are expected to be the highest contributors to Europe’s energy savings by 2030.

Executive summary

The transition of Europe’s neighbourhoods to net-zero energy districts is underway.
The implementation of the EU 2020 energy and climate targets triggered the transformation of Europe’s neighbourhoods to net-zero energy districts. Frontrunner municipalities have set ambitious targets to reduce their energy demand and to increase the share of their energy supply from local renewable energy sources. European municipalities set their energy targets in different ways and the timeline to meet the agreed target at a local level varies from one municipality to another.
Hvar, the remote Croatian Island, as well as the municipality of Val-de-Ruz, in Switzerland, have set a target to be self-sufficient. However, the former aims at meeting its self-sufficiency target to be 20% by 2020 while the latter aims to be totally selfsufficient by 2030. Similarly, the municipality of Helsingor in Denmark aims for carbon neutrality by 2050 while Cloughjordan in Ireland aimed at building an eco-village in a rural area. Other municipalities such as Salzburg in Austria developed a 2050 smart city roadmap while Valby in Denmark set a renewable energy target and the municipality of Zaragoza in Spain developed and implemented a holistic bioclimatic design at neighbourhood level.
The definition of the target and the timeline to achieve the agreed target influence the selection of measures and sectors to consider. Importantly, making buildings highly energy efficient is a common component in each of the 61 identified European projects. However, in order to meet their energy targets, less than 50% of the identified projects considered both the renovation of existing buildings and the construction of new buildings to low-energy consumption standards. Additionally, data on the achieved energy consumption and the supply from renewables in the use phase as well as investment data were identified only for seven projects.

Municipalities consider the energy transition of their neighbourhoods as an opportunity to address their local socio-economic concerns.

Municipalities positively regard the holistic transition of their neighbourhood to net-zero energy districts. Building consensus around ambitious energy targets is easier if the energy transition complements other local projects and contributes to addressing local and regional socio-economic concerns, as shown by the seven case studies analysed in this report. The self-sufficiency target of Hvar project, in Croatia, addresses the concern that remote islands have regarding their reliance upon mainland energy supply, as well as having to deal with waste treatment locally. Similarly, the Cernier project (Val-de-Ruz in Switzerland) was about demonstrating that municipalities can be energy independent. Furthermore, the central objective of Lehen district in Salzburg was sustainable urban renewal aiming at improving the quality of life of the whole community while Valby municipality in Denmark aimed at improving its image, attracting young residents and becoming a green district. Zaragoza in Spain, Cloughjordan in Ireland and HelsingorHelsingborg in Denmark/Sweden aimed at being showcase examples and laboratories for
new urban planning and building design. The approach undertaken by these three projects has been a win-win approach from energy, visibility and exemplarity perspectives. Each of them is regarded as a best practice area and attracts tourists and
experts to learn about the modern state-of-the-art efficient building and renewable energy supply practices.

Public finance (EU and national) has been instrumental in unleashing the transition to net-zero districts.

Identified projects have all benefited from receiving public finance. The municipalities usually leverage EU Finance, in the form of grants and/or loans, with national and local funds including such from private investors. In the identified projects, public finance allowed for the ambition of energy requirements to be increased, testing new technologies, building technical capacity, raising awareness and ensuring citizens’ engagement in the energy transition. In Helsingør and Hvar, public finance allowed city councils to develop an ESCO model. In Salzburg, public finance allowed stakeholders to develop a “high-quality agreement” which defines the energy concept as well as the role and responsibilities of each stakeholder. In Valby and Zaragoza, public finance allowed for the involvement of researchers from universities and for documentation of the
projects to be written up, enabling others to have access to lessons learned from practice and to better understand users’ behaviour. Similarly, the use of public finance in Cloughjordan unleashed the Irish energy performance certificate database while in Helsingor-Helsinborg project public finance allowed for testing of prefabricated building elements, which is now a new construction practice imported to Denmark from Estonia.

Energy transition of Europe’s neighbourhoods has led to the emergence of new actors and to setting innovative governance structures.

An important feature of the seven districts analysed in this report is the emergence of new actors and the innovative governance structures set by municipalities to ensure all necessary actors are involved and their roles as well as their responsibilities are well and clearly defined. The involvement of actors varies from one municipality to another; whether the developers involve the entire population, local businesses and investors in the energy transition of their neighbourhoods differs from project to project. The Centre of Urban Sustainability (CUS) in Zaragoza acts as a permanent exhibition as well as an interpretation centre to educate and disseminate projects’ results to a wide range of people. Trainings and interventions provided in schools and universities around Valby project have been essential elements contributing to the success of this project.
Similarly, Salzburg pioneered the “high-quality agreement” to engage multiple stakeholders and to ensure their full participation in the governance of the project. Sustainable Projects Ireland, a local NGO, had the responsibility of developing the ecovillage of Cloughjordan, while municipalities of Helsingor and Helsinborg created a whole community approach by providing training on energy sustainability for janitors and SMEs. Overall, the role of these new actors in the design and the implementation phase of the identified projects is indisputable. However, the levels of engagement of these new actors in the use phase of each project are difficult to assess. Monitoring the level of engagement of different actors after the implementation of energy measures is an area to explore by social science researchers.

Modern technologies make the transition to net-zero energy districts a reality.

Modern technologies are pivotal in the energy transition. The use of modern technologies in the seven projects analysed in this report included

  • i) the use of smart meters to monitor energy consumption,
  • ii) the use of modern communication tools and social
  • media platforms to raise awareness and to update stakeholders on the progress made in each project and in the case of the Danish example
  • iii) the use of prefabricated building elements imported from Estonia to deliver on the high ambition of the project at an affordable cost.

The latter is getting more attraction since Energiesprong project. In fact, the project used digitalisation technologies such as 3D-scanning and Building Information Models (BIM) to prefabricate off-site the buildings elements needed to renovate social housing, constructed in the sixties, to net-zero energy. Energiesprong was first implemented in the Netherlands and, more recently, EU funding allowed for the expansion of the practices to France and the United Kingdom (UK). The use of digitalisation technologies for renovation reduced on-site intervention to one week and helped deliver net-zero energy renovations. Furthermore, it is expected that scaling-up the use of digitalisation technologies in energy renovation would allow a sharp decrease of the cost of net-zero energy renovation making it affordable for all while improving the productivity of the construction industry. Moreover, the implementation of smart-meters, if well-combined with sensors, could be an opportunity for a better understanding of user’s behaviour. Overall, modern technologies are expected to make the future of energy transition brighter.

This publication is a Technical report by the Joint Research Centre (JRC), the European Commission’s science and knowledge service.

Contact information
Daniele Paci, : European Commission, Joint Research Centre, Via E. Fermi, 2749. 21027 Ispra. VA, Italy
EU Science Hub:

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