On March 24th, 2025, the European Committee of the Regions in Brussels hosted the concluding conference of the syn.ikia project —a culmination of five years of intense collaboration, innovation, and ambition. Experts and professionals from research, government, housing, and industry came together to reflect on syn.ikia’s achievements and explore how Sustainable Plus Energy Neighbourhoods (SPENs) can contribute to a fair, inclusive, and climate-resilient future.
Five Years, Four Countries, One Ambitious Goal
Project leader Niki Gaitani from the Norwegian University of Science and Technology (NTNU) emphasized the critical role of Sustainable Plus Energy Neighbourhoods (SPENs) in driving climate-resilient urban development .
During her presentation, she outlined the project’s key highlights and achievements, showcasing its innovative approach to sustainable neighbourhood design and implementation. Through the syn.ikia project, four demonstration neighbourhoods were successfully implemented across distinct climate zones—Verksbyen in Norway, Uden in the Netherlands, Barcelona in Spain, and Salzburg in Austria—delivering a total of 363 housing units.
These neighbourhoods serve as living proof that energy-positive, inclusive, and socially resilient urban design is not only possible—but already happening.
Each real-life project demonstration incorporated cutting-edge energy solutions such as integrated neighbourhood-scale design, predictive digital twins, energy efficiency and energy flexibility measures. In total, syn.ikia delivered 14 innovative tools and methodologies, supported by 17 core key performance indicators that assess environmental, economic, and social impact.
The Neighbourhood: a strategic Scale for Transformation
The syn.ikia project has demonstrated that neighbourhoods are a pivotal scale for accelerating the decarbonisation of the built environment. Unlike single-building upgrades, neighbourhood-level initiatives enable integrated solutions—shared energy systems, mobility services, and green infrastructure—that yield both environmental and social co-benefits. This place-based approach fosters local ownership, supports inclusive design, and ensures more efficient use of public resources. To help quantify these effects, syn.ikia developed the Multiple Benefits Tool, which highlights impacts such as improved air quality, reduced energy poverty, and greater wellbeing. By linking climate action with social resilience, the neighbourhood model offers a scalable path toward just and sustainable living.
As part of the latest recasts of the Energy Performance of Buildings Directive, the Renewable Energy Directive II, and the Energy Market Design Directive have, for the first time, begun to reflect the value of the neighbourhood scale—marking a shift toward more systemic, people-centred energy policy.
Key themes from the final conference
Bringing together voices from the European Commission (DG GROW and DG ENER), the European Parliament, Housing Europe, municipalities, and syn.ikia’s project partners, the final conference highlighted the project’s broad relevance across sectors.
Special thanks go to the moderators who guided the day’s discussions with insight and clarity: Inger Andresen (NTNU), Clara Mafe (Housing Europe), Victoria Taranu (BPIE), and Caroline Cheng (SINTEF). Their contributions helped frame the complex intersections of housing, energy, and policy—ensuring that the diverse voices of the syn.ikia consortium and its stakeholders were heard and connected throughout the event.
Several core themes emerged throughout the day:
With over 15 partners from 7 countries—including researchers, public housing providers, architects, municipalities, and private developers—syn.ikia was built on a strong interdisciplinary partnership. This structure allowed the project to test scalable solutions across diverse local realities, combining technical innovation with social and policy insights.
Sorcha Edwards, Secretary General of Housing Europe, underlined the importance of such partnerships in delivering real change, particularly when working with public, social, and cooperative housing actors. The ability to co-create with local housing providers and authorities, she noted, is essential to ensuring that energy transition does not come at the expense of affordability or social cohesion.
Affordability featured prominently throughout the discussions. As Andres Jaadla, from the Estonian Union of Housing Associations and member of the European Committee of the Regions (rapporteur for an opinion on Smart, sustainable and affordable housing as a tool for local authorities to face multiple challenges), noted, rising housing and energy costs are placing increasing pressure on households across Europe. While syn.ikia’s primary focus is on sustainability, its neighbourhood-scale approach also ensures long-term cost stability through energy-efficient design, integrated renewable systems, and smart technologies.
Yet as many speakers emphasized, affordability must also be addressed at the funding level. Sorcha Edwards stressed despite the strong interest in the public, cooperative and social housing sector in decentralizing energy production, there is a need for stronger support mechanisms to ensure public, cooperative and social housing providers can access the resources needed to deliver energy-positive neighbourhoods at scale. Without extensive public or (publicly regulated) private investment SPENs are not possible. Initiatives such as Denmark’s National Building Fund were showcased as inspiring examples of how public-private financing can help make ambitious models like SPENs both accessible and replicable.
Although syn.ikia showed that SPENs are technically feasible, several speakers pointed to regulatory barriers as a major bottleneck. Ole-Edvin Utaker from Arca Nova Group emphasized that “technology is not the issue—regulation is,” highlighting the need for policy frameworks to catch up with the pace of innovation.
Calls were made for a more flexible and enabling policy environment—particularly to support decentralised energy systems and neighbourhood-level energy sharing. Without these frameworks, the full potential of SPENs to deliver energy efficiency, flexibility, and social value remains out of reach. Henrik Madsen (DTU) highlighted the critical role of buildings in providing flexibility to the energy system, stressing that while energy efficiency remains essential, energy flexibility must receive equal attention. He called for a shift in mindset—across grid design, tariffs, and regulation—towards a data-driven approach that enables smarter, more responsive neighbourhoods.
Building on the theme of regulation and innovation, Jaume Salom (IREC) underlined the potential of energy flexibility to optimize the use of local renewable resources He highlighted a key lesson from syn.ikia: energy flexibility enhances self-consumption while mitigating grid overload, enabling a more efficient and resilient energy system. A fundamental solution to achieving this is energy sharing, which facilitates the collective management of resources at the neighbourhood level. This highlights the urgent need for regulatory frameworks that not only permit, but actively support, decentralized and collective energy management models at the neighbourhood level.
Engaging residents early and meaningfully was a cornerstone of the syn.ikia approach. Inge Strassl from Salzburg Institute for Spatial Planning and Housing (SIR) spoke about the importance of building trust with tenants and involving them from the beginning. In Salzburg’s demonstration project, early dialogue helped ensure buy-in and satisfaction—showcasing how people-centric design strengthens not only social outcomes but also the long-term success of energy solutions.
In Barcelona, Joan Estrada (INCASÒL) emphasized that syn.ikia served as a catalyst to go beyond business-as-usual. The Spanish demonstration became part of a broader neighbourhood regeneration strategy, helping to embed sustainability and inclusivity into a traditionally complex urban context. “The project encouraged us to look beyond the building,” he noted, highlighting the importance of surrounding infrastructure for enabling energy exchanges. While this holistic approach increased administrative complexity—especially in maintaining decentralised systems—it also underscored the need to rethink project development responsibilities, including expanding the role of energy certifiers.
From the Netherlands, Hugo de Vries (Area Wonen) reflected on how syn.ikia enabled the organisation to deliver higher service quality while lowering costs. The ability to predict energy production more accurately led to better integration with grid operators—though it also required them, and tenants, to adapt. “Behaviour change is part of the process,” he noted, pointing to the need for support as residents engage with new technologies.
This participatory approach resonated across the board, especially among those working in public and cooperative housing contexts, where social acceptance is as crucial as technical performance.
From shared mobility to renewable energy communities and local heating and urban cooling plans, the neighbourhood emerged as a powerful scale for integrated policy action. Ciarán Cuffe, urbanist and former MEP, alongside Adrian Hiel of Energy Cities, argued that neighbourhoods offer a unique sweet spot—large enough to benefit from economies of scale, yet small enough to be tailored to local needs.
Several speakers emphasised that thinking at the neighbourhood level opens the door for new governance models, collective ownership, and more efficient use of public investment—all essential for a just green transition.
As the policy landscape evolves, the challenge lies in translating EU-level ambition into national frameworks that support local action. Julien Tami of DG ENER pointed out that while the revised Energy Performance of Buildings Directive (EPBD) sets a strong direction, its success will depend on how Member States empower municipalities and housing providers to act. The EPBD provides an opportunity of multilevel governance and collaboration at national, regional and local levels through the implementation of the National Buildings Renovation Plans and Trajectories for progressive renovation.
Ciarán Cuffe encouraged stakeholders to actively engage with national renovation and energy planning processes, ensuring that the neighbourhood dimension—and its potential for inclusivity—is fully integrated. Echoing this sentiment, Karel Vanderpoorten from DG GROW stated: “Social innovation is a key driver for change. Projects like syn.ikia show what’s possible—and Europe is listening.”
syn.ikia has shown that Sustainable Plus Energy Neighbourhoods (SPENs) are both technically feasible and socially valuable. To scale these models, however, supportive financing and policy frameworks are essential.
Public national banks are vital intermediaries in delivering affordable finance for public, cooperative, and social housing. EU funds must be aligned with environmentally responsible housing investments to attract private capital and enable long-term, inclusive neighbourhood development.
Bundling projects at the neighbourhood level—as done in syn.ikia—helps meet investment thresholds and improves access to funding. SPENs in the social housing sector also uniquely align with all three ESG dimensions and EU taxonomy goals, offering a powerful case for targeted EU support.
These priorities echo the current advocacy of Housing Europe, which calls for stronger EU financing tools, improved access to funds, and recognition of neighbourhood-scale initiatives as key to the just green transition.
To unlock this potential, reforms are needed: better de-risking tools, updated State aid rules, and stronger incentives for area-based planning. With models and tools already in place, what’s now required is bold investment and policy alignment to bring SPENs to scale.
But what is the legacy of syn.ikia?
While five years were not enough to fully establish Sustainable Plus Energy Neighbourhoods (SPENs) as a mature concept, the syn.ikia project has laid a strong foundation for continued advancements. The 15 project partners remain optimistic that their work will serve as a catalyst for future developments in sustainable urban living.
Comprehensive Monitoring and Evaluation – syn.ikia is among the first projects to systematically assess more than 30 key performance indicators (KPIs) spanning energy efficiency, indoor environment quality, economic feasibility, and social impact.
Innovative Solutions – A portfolio of 14 proven innovations, all accessible through the syn.ikia Innovation dashboard, providing valuable tools for future projects.
Extensive Knowledge Base – Over 30 published research papers and more than 50 public reports, offering deep insights into SPEN implementation and sustainability strategies.
Tangible Impact – The creation of more than 300 housing units for social and public housing, alongside 44 privately developed apartments, demonstrating the feasibility and scalability of sustainable plus energy neighbourhoods.
Looking Ahead
As the syn.ikia project wraps up, its legacy continues to grow. The project’s tools, learnings, and demonstration sites are already informing EU policy, national strategies, and local development. One of its key outcomes, the SPEN Compass, now serves as a practical guide for communities seeking to replicate and scale syn.ikia’s success.
At a time when urgent action is needed for both people and the planet, syn.ikia has demonstrated that a just, inclusive, and climate-resilient future is not merely an aspiration—it is already taking shape, one neighbourhood at a time.
