PED Topic 3: Sustainable PEDs, flexibility in energy systems, and integrated technologies

Flexibility in energy systems and the integration of energy technologies are core pillars of PEDs, enabling districts to balance demand with variable renewable generation, manage local surplus, and ensure secure and resilient energy supply. However, despite extensive modelling and design efforts, real-world implementation and long-term validation of integrated, flexible energy systems remain limited. Natural fluctuations, combined with user behaviour and infrastructural capacities in renewable energy supply pose significant challenges for grid stability and efficient system operation. The diversity of energy carriers, technologies and stakeholders, combined with fragmented data standards, proprietary protocols and misaligned regulatory frameworks, hinders interoperability and coordinated operation. As a result, there is insufficient evidence on technical performance, economic viability and social acceptance, including user engagement. Addressing these challenges through real-world urban demonstrations is essential to understand behavioural drivers, validate system integration, and support the scalable deployment of flexible, integrated energy solutions.

Proposals under this topic must develop context-sensitive and scalable approaches for integrating energy system flexibility and integrated technologies into PEDs. The objective is to enable PEDs to operate as reliable, resilient, and energy-positive systems by coordinating electricity, heating, cooling, and mobility through multi-carrier flexibility solutions that support local and regional energy systems. Projects should embed, demonstrate and validate integrated technological and digital flexibility solutions, including electrical and thermal storage, demand response, controllable loads, sector coupling (power-to-heat, power-to-X), e-mobility, V2G, and decentralised renewable generation at district scale. Proposals need to explore coordinated operation into the planning, design, implementation, and operation of PEDs, supported by adapted regulatory, market, and data governance frameworks,  and demonstrate how energy demand and supply can be aligned with variable renewable generation through smart energy system design, temporal balancing, and coordinated control. This includes smart energy system design, temporal balancing, forecasting, and control strategies that considers for natural supply fluctuations, user behaviour/ consumption patterns and infrastructural constraints. Proposals are expected to explore regulatory, market, data governance, and interoperability adaptations, as well as innovative and blended financing and business models that enable flexible services, de-risk investments, and support scale-up.

PED flexibility solutions must be connected to wider urban and regional energy systems, overall grid services and grid ownership structures, providing solutions for grid congestion and enabling demand response, energy sharing, storage, sector coupling, and participation in flexibility and energy markets, thereby enhancing system efficiency, resilience, grid stability, and climate neutrality. Thus, the specifics of a balancing role of PEDs and local energy solutions in general need further exploration, elaborating on the (positive) impact of not least the overall resilience of European energy systems.

In this context, proposals need to explore the roles of municipalities, utilities, aggregators, grid operators, technology providers, building owners, mobility operators, as well as energy communities and citizens in planning, implementing, operating, and monitoring flexibility-enabled PEDs. Proposals should develop governance, coordination, and market models and demonstrate scalable approaches applicable across diverse urban contexts, PED typologies, and regulatory environments, ensuring fair distribution of costs and benefits. Proposals should consider approaches for strengthening social acceptance and user participation addressing behavioural drivers, trust and incentives through engagement of residents, energy communities, SMEs, and local stakeholders. Solutions should demonstrate shared local benefits, including improved energy affordability, enhanced system reliability, increased renewable integration, and opportunities for local value creation through flexibility services.

Questions:

• How can integrated context-sensitive flexibility solutions across energy carriers, sectors, and actors be effectively designed, governed, and validated in real-world PEDs to enable resilient, scalable, and socially accepted sustainable energy systems?
• What governance frameworks, market arrangements, digital interoperability models, and financing mechanisms can enable diverse actors and citizens to co-create, operate, and scale flexibility in PEDs?

Rather than focusing on individual technologies, projects are expected to adopt systems thinking and place-based approaches that integrate technical, digital, economic, and social innovation. Outcomes should be impact-oriented, evidence-based, and user-centred, supporting the large-scale deployment of flexibility-enabled PEDs.

Projects should clearly define their expected qualitative and/or quantitative outcomes, supported by measurable indicators, facts, and figures. Expected impacts include, but are not limited to:

• Coordinated operation of electricity, heating, cooling, and mobility systems at the district scale, demonstrating improved energy efficiency, renewable energy integration, and system reliability.
• Demonstration on how local flexibility solutions can contribute to mitigate grid congestion challenges and support local and regional grid operation
• Demonstration of multi-carrier flexibility technologies, including electrical and thermal storage, demand response, controllable loads, sector coupling, district heating and cooling, and e-mobility/V2G etc., operating as a coherent system.
• Proven digital and ICT architectures such as digital twins, agent-based or AI-supported control, interoperable data models, and secure data exchange across urban infrastructures.
• Evidence-based assessment of planned versus realised flexibility potential, supported by long-term monitoring of technical, environmental, and economic performance and contributions to grid stability and resilience.
• Scalable approaches for overcoming interoperability barriers, including open interfaces, shared communication protocols, and reference architectures applicable across technologies and vendors.
• Validated local market and governance models, such as local flexibility markets, peer-to-peer trading, virtual power plants, and energy community frameworks, enabling clear distribution of benefits.
• Improved understanding of social acceptance and behavioural aspects of energy flexibility, including user participation, incentives, and trust.
• Policy, regulatory, and standardisation recommendations, alongside replicable PED flexibility concepts and implementation guidelines, supporting scaling across European cities and regions.