The climate emergency and global decarbonization targets present an urgent challenge. Municipalities across Spain are taking steps to reduce their CO₂ emissions, both in industry and in households. Local governments have tools at their disposal to drive this transition, and Sant Cugat del Vallès has traditionally been a pioneer in implementing measures to support residents, primarily through tax incentives such as reductions in property taxes.
However, in 2025, the City Council identified growing interest among residents in establishing an energy community through the participatory budgeting process. The local government decided to go one step further, creating a space where citizens could make decisions, organize themselves, and take control of their own energy transition.
The challenge of engaging, mobilizing, and building a community
Making this shift a reality required more than simply launching a participatory budgeting process. It meant engaging residents, raising awareness, and encouraging people to organize collectively. This was the twofold challenge presented to ePlural, which took it on together with the Tandem Social team.
The first priority was raising awareness and mobilizing residents. Two participatory events were organized, and outreach materials (brochures and social media content) were developed to connect with the local community. The response was a success: more than 60 people from different backgrounds and age groups participated, with a higher proportion of young people than usual.
During this process, it became clear that Sant Cugat already had a significant number of individual solar photovoltaic installations and many residents generating surplus energy. This shared concern created an opportunity to build a network.
The second priority was establishing a core working group. The initial interest needed to be transformed into a stable structure. Twelve committed residents came together to form a steering group responsible for developing the roadmap. During this process, the team discovered that an energy community already existed in the municipality. Rather than duplicating efforts, they decided to join forces and expand the existing initiative.
From individual rooftops to a community-owned energy network
This process of support and community building has resulted in a successful model with a tangible, direct impact on the local area. The initial mobilization of more than 60 participants during the awareness-raising events, together with the active involvement of a 12-member steering group, provided the momentum needed to integrate the initiative into an existing community structure. Today, the expanded energy community has more than 50 members working together to launch its first shared service: the development of collective solar photovoltaic installations.
At the same time, the project has opened up an entirely new approach to managing surplus energy within the municipality. Together with Arkenova, another cooperative member of ePlural, an open call has been launched for residents who already have individual solar installations that generate surplus electricity. The aim is to connect them directly with community members who are unable to install solar panels themselves. Work is currently underway to define a regulatory framework and fair pricing agreements that will formalize these arrangements between neighbors.
The Sant Cugat initiative represents a pioneering experience in collective energy management. In recent years, energy has become an increasingly important concern for citizens. At Tandem Social, we firmly believe that when people share a common goal and are given the right spaces to come together, collective solutions emerge naturally. Supporting public administrations and citizens in transforming individual challenges into tools for community impact is an essential part of our mission.
Technology to sustain transformation
Creating and maintaining energy communities requires a significant amount of volunteer time and effort from local residents. To ensure the project’s long-term sustainability and prevent volunteer burnout, specialized organizations such as ePlural, using the tools provided by Som Comunitats, take on the most demanding technical and administrative tasks, freeing the community from this burden.
This process has also been made possible thanks to the support of Sant Cugat del Vallès City Council, which has promoted the initiative through its energy transition and citizen participation policies. The project has benefited from technical support provided by the Barcelona Provincial Council, enabling access to specialized assistance in facilitating, defining, and consolidating the local energy community.
The involvement of the City Council’s Citizen Participation, Communications, and Environmental Technical Services is also worth highlighting. These departments have supported the process from its initial stages, facilitating coordination among the various stakeholders, providing technical expertise in energy and sustainability, and ensuring that the project contributes to the municipality’s decarbonization, energy sovereignty, and climate change mitigation goals, as outlined in the Sustainable Energy and Climate Action Plan.
The Collserola Sostenible Local Energy Community demonstrates how collaboration between public authorities, specialized cooperatives, and organized citizens can accelerate the energy transition and generate environmental, social, and economic benefits for the municipality as a whole.
