Flex Ready® - The French solution for tertiary flexibility

This lack of interoperability results in high integration costs, vendor lock-in and limited scalability of flexibility services, and underutilisation of available demand-side resources. Against this backdrop, this paper investigates how the standardisation of data exchange between building control systems and energy market actors can act as a key enabler for large-scale flexibility in modern power systems.

1 The goal of the paper is to analyse the role of interoperable data models and interfaces in unlocking both explicit and implicit flexibility, and to assess their impacts on the main stakeholders of the electricity value chain. It focuses in particular on the interaction between building automation systems, aggregators, electricity suppliers and system operators, and on how a shared data exchange framework can support market development, operational efficiency and system reliability.

The paper adopts a mixed qualitative and analytical approach. It builds on a review of existing flexibility mechanisms, building control architectures and smart-grid communication practices, combined with a detailed analysis of data flows required to activate, monitor and settle flexibility services. Stakeholder use cases are examined to identify key information needs, including availability, activation status, delivered performance and price signals. From this, a harmonised data exchange framework is derived, designed to support interoperability across technologies and market roles while remaining compatible with existing smart-metering and control infrastructures.

The results show that standardised data exchange significantly lowers the technical and economic barriers to flexibility deployment. For aggregators, it reduces project-specific engineering, improves operational monitoring and supports more liquid and competitive flexibility markets. For electricity suppliers, it increases the effectiveness of dynamic pricing by ensuring that price signals are consistently translated into load modulation at the customer level. For building control system providers, it stimulates market adoption by reducing customer dependency on proprietary ecosystems. Consumers and building managers benefit from reduced vendor lock-in and from the ability to aggregate and optimise flexibility across multi-building portfolios. Finally, both distribution and transmission system operators gain access to a broader base of controllable assets, improving congestion management, system balancing and security of supply.

Overall, the paper demonstrates that data exchange standardisation is not merely a technical layer but a strategic enabler for the transition to flexible, decentralised and digitalised power systems.

By aligning the needs of market actors and control technologies, it provides a foundation for scaling demand-side flexibility as a core component of future electricity system operation.