The European Network of Transmission System Operators for Electricity (ENTSO-E), comprising 40 TSOs across 36 countries, plays a pivotal role in overseeing and coordinating the safe operation of Europe’s highly interconnected power grid. As Europe integrates more renewable energy and embraces digital transformation, a key observation which has emerged is that TSOs have reached a pivotal point where existing supervisory control and data acquisition (SCADA) systems are no longer sufficient and energy management system (EMS) platforms are proving inadequate in addressing the evolving needs of TSOs. These traditional systems, typically sourced from single vendors, often lack the flexibility and interoperability needed to adapt to increasingly dynamic grid conditions. In its strategic vision to enable the continent’s transition toward climate neutrality by 2050, ENTSO-E emphasises the importance of resilient, flexible, and future-proof control room infrastructures. According to the ENTSO-E’s Research Development and Innovation Roadmap 2024–2034 also, one of the missions of the TSO community is to enhance control and interoperability through digitalisation.
To this end, in May 2025, ENTSO-E released a new position paper on ‘Vendor agnostic solutions (VAS) for next-generation control room eco-systems’, outlining the vision for modular, interoperable ecosystems that address the growing complexity of European power systems and the limitations of legacy SCADA/EMS infrastructure. The study was conducted by the Working Group Digital and Communication under the Research, Development, and Innovation Committee. ENTSO-E’s VAS task force (TF), comprising a group of TSOs, has identified seven core tenets for a new modular ecosystem viz., transparency, modularity for scalability and flexibility, standardisation, integration, digital and cyber resilience, separation of concern and new ways of working.
Transparency
Transparency is a core tenet of the proposed control room architecture. In this context, transparency refers to making system-related information, such as software design, architecture, project processes, and technical documentation, openly accessible to all relevant stakeholders. This includes not only TSOs but also vendors, distribution system operators (DSOs), and regulatory authorities. The VAS TF classifies transparency into information transparency and process transparency. The former includes software artefacts such as requirement documents, design documents and (optionally) code alongside commercial products and also refers to the need for buyers or users to conduct code security, quality scanning and verification. Meanwhile process transparency refers to the software’s ability to reveal how it works, what it does and how it does it. This can be categorised into automated (software) and unautomated (organisational or business operation) processes. Distinguishing between the two requires defining corresponding factors to measure transparency.
The framework proposed by ENTSO-E promotes both information and process transparency. The purpose of the transparency framework envisioned by the VAS TF is to promote the idea of transparent information, processes and software sharing within the TSO community, with the ultimate goal of sharing this vision with software providers. By sharing such information through standardised interfaces and clear documentation practices, ENTSO-E envisions a collaborative ecosystem where innovation is nurtured, accountability is maintained, and siloed operations are minimised.
Modularity for scalability and flexibility
Modular architecture refers to a system made of separate components (modules) that are connected but not dependent on each other. A modular system architecture is central to ENTSO-E’s vision for next-generation control rooms. In such systems, functionalities are encapsulated within discrete, self-contained software modules that interact via standardised interfaces. These modules are reusable, independently deployable, and designed to operate within an application platform that hosts shared services and middleware components. This design allows modules to be easily reconfigured, updated, or replaced without disrupting other components of the ecosystem. The overall objective is to develop a framework for modules in control centre ecosystems that align with TSO governance.
To ensure interoperability and functional integrity, each module must comply with a clearly defined modular contract. This contract outlines the module’s role, input/output data specifications, dependencies, service requirements, and version control mechanisms.
Modular contracts, when standardised across providers and TSOs, enable plug-and-play functionality, which allows quick turnover times for replacing or upgrading modules.. The modular approach also supports faster system evolution, minimises vendor lock-in, and facilitates custom tailoring of software solutions across diverse grid contexts.
Standardisation
Larger utilities, including TSOs and large DSOs, typically must comply with various externally imposed standards to ensure interoperability, reliability and efficiency in managing the transmission grid and when operating outside these cooperative and regulatory standards, the utilities must consider which standards to use when building their ecosystem. The VAS TF recommends the use of established international, open and – if no other standards are available – industry standards as a first priority, followed by commonly agreed standards. The new ecosystem encompasses several domain areas and aspects that will need to be described and standardised for integration, operation and other relevant processes. ENTSO-E identifies several domains where standard-setting is crucial. These include internal and external interface protocols, data exchange formats, graphical user interface (GUI) design, security practices, system modeling, and the technical platforms supporting cloud or on-premise deployments.
Once the above standards are in place, they would require governance which should be maintained by a body independent of any individual TSO. The position paper recommends that these standards must be forward-looking, anticipating emerging technologies, as the modular nature of the ecosystem will allow TSOs to upgrade/exchange modules at a faster rate than in the previous paradigm. In a subsequent step, a body could also develop tools to confirm that modules comply with the agreed-upon standards. Additionally, it could register compliant modules to a common database for TSOs for easy access to market offerings.
Integration with existing systems
The newly developed modules may not be able to provide for all the functions for the TSOs and hence the TSOs may want to retain parts of their existing systems without violating the basic principle of the modular ecosystem concept. Therefore, seamless integration of new modules with existing systems is critical. This applies not only to the transition phase as the TSO shifts to the new ecosystem but can also be valid as a permanent solution. However, whether a TSO wants to continue using existing systems on a permanent basis can only be decided on a case-by-case basis for each TSO and system.
The transition to a modular control room cannot be abrupt; instead, it must allow for hybrid environments where new modules coexist and interact with established platforms. Integration must be achieved through the development of robust, well-documented interfaces capable of secure, real-time data exchange.
Various factors may justify the continued use of legacy systems, such as recent investments, multi-stakeholder ownership models, or the absence of viable modular alternatives. The goal is not to replace legacy systems outright, but to integrate them into a broader ecosystem that facilitates incremental modernisation. For non-time-critical functions, simple data exchange mechanisms—like file transfers—may suffice. For more complex integrations, custom interfaces developed in cooperation with original vendors may be required. The flexibility of the modular design ensures that TSOs can manage this integration process at their own pace and with minimal operational disruption. Well-developed integration capabilities, including into domain-specific legacy systems, are therefore crucial for the practical feasibility of a modular ecosystem.
Digital and cyber resilience
As the power grid becomes increasingly digital, ensuring its security and resilience is paramount. The new ecosystem, its modules and its operation should be resilient by design, applying zero-trust principles. Additionally, the information and processes must have a high level of integrity, identifiable entities and verifiable and secure information exchange on and into the ecosystem platform. The future control room ecosystem will be required to function in any power system operational state, whether normal, alert, emergency, blackout or power system restoration. Hence, it should incorporate an overall resilience concept, covering any type of incidents, securing operational continuity and providing fast recovery if any function should fail. To prepare, detect, respond, recover and review every aspect of digital and cyber resilience, there are certain key principles which should serve as a guideline for a future ecosystem. These include system and process documentation, information and process integrity, secure and standardised communication, system and process surveillance, cybersecurity, IT emergency preparedness, disaster recovery, self-healing IT systems and N-1-1 redundancy, information decoupling, vendor and technology robustness and diversity, segregation and isolation, security by design and distributed infrastructure and controls.
Separation of concerns
Currently, majority of European TSOs operate a non-modular system for their control centres, relying on one or a few vendors to provide a core system with all the necessary functionalities. This results in vendor lock-in and limits adaptability to new circumstances or technologies. Also, it would take a great deal of investments and multiyear projects to replace the entire system with a new non-modular system. Although the non-modular systems can be integrated into a modular system and multiple functionalities may be bundled and sold together with a single point of contact with the ecosystem, this can devolve into a new rigid system over time. To prevent non-modular systems from establishing themselves, adherence to a design principle from the software engineering world is recommended. “Separation of concerns” is a design principle that advocates for dividing a software system into distinct sections, each addressing a separate concern or functionality. By isolating different aspects of the system, such as data management, user interface and business logic, providers can work on and implement individual components independently without affecting others. This separation not only simplifies debugging and testing but also promotes code reuse and scalability.
However, in the case of multi-vendor delivery (one of the main drivers of modularisation), full avoidance of redundancy is infeasible, as it would create numerous interdependencies, making delivery and operation contracts overly complex.
Separation of concerns structures the ecosystem into three logical layers: modules, application platforms, and technology platforms. Each module is a self-contained functional unit interfacing with the application platform, which provides the underlying middleware, application programming interfaces (APIs), and shared services. Each module will have a module contract with both the application platform and the technology platform to which it is to be connected. The application platform ensures that modules can work together seamlessly, manage dependencies and handle shared services such as security, logging and data storage. A standardised set of shared services (both minimum and optional) should be defined to ensure module compatibility between TSOs. The last layer, the technology platform comprises the physical and virtual infrastructure required for operations. It includes hardware, operating systems, databases and network infrastructure and covers functions such as storage and security and will dictate which standards are used to connect the other layers.
This layered structure enables independent module development, testing, and deployment, minimizing vendor lock-in and supporting the gradual evolution from monolithic to fully modular systems.
New ways of working
While modular design is important, its success equally depends on effective deployment, operation, and continuous enhancement of these modules. A key advantage of modular systems over traditional, monolithic ones is the ability to release small, frequent software updates in short agile cycles. After thorough testing, these can be deployed regularly, enabling development closely aligned with user needs through feedback loops. Additionally, automation can streamline building, testing, and deployment. However, manual testing still remains essential especially in critical infrastructure like energy to verify not only functionality but also the high availability and reliability vital for grid operations. With infrastructure-agnostic modules, TSOs can choose their preferred hosting environment, whether public cloud, private cloud, or on-premise. Given the criticality of energy systems, on-premise deployment often offers the best control and security, enabling TSOs to directly manage operations. In many cases, module downtime can cause significant disruptions or even blackouts, so 24/7 support is essential for most TSO-deployed modules, as it would otherwise hinder the reliable operations of the power grid. Another critical aspect to look out for is the continuous software adaptation in view of the rapid transformation of the energy sector. For this, flexible, modular systems with agile development capabilities make it easier to address new needs quickly. This integration fosters a resilient, adaptable IT environment that supports TSOs in maintaining secure, efficient, and reliable grid operations despite an evolving regulatory and technological landscape.
The position paper also advocates for a legal and collaborative framework which is essential to allow modules to be legally distinct in terms of liability and guarantees. Legal separation enhances flexibility, making it easier to adapt to changing laws without widespread impact. The ecosystem supports integration of open-source, proprietary, and commercial modules. Each approach offers unique benefits and trade-offs in cost, customisation, support, and innovation. The collaborative environment enables TSOs to co-develop, license, or share modules, creating a dynamic marketplace for tailored solutions.
Cross-source compatibility is another area that the task force stresses on. Strategically combining modules from all sources can create stronger synergistic benefits that translate to increased functionality, security and control across the control centre infrastructure. The increased level of choice that a modular infrastructure provides, especially as additional business models enter the market, can be highly beneficial for both TSOs, who gain greater choice, and classical providers, who can focus on core competencies.
The new ways of working tenet also includes the new provider collaboration. A shift to a modular ecosystem built on the principle of separation of concerns implies a new relationship with classical providers, which must be established and will lead to the creation of new market models. The new ecosystem would allow smaller packages to be created in the form of modules. These modules can be built in several ways, wherein a provider can be requested to build an individual bespoke module or an “off-the-shelf” module with some customisation; a third party can develop smaller bespoke modules that work with already existing modules; a TSO can develop its own bespoke module using internal or external development teams or can license modules from other TSOs; collaborative development can be undertaken between several TSOs for a common module; and self-developed/open-source modules can be traded between TSOs. The new modularity would also allow modules to be developed in shorter time increments than existing systems. Avoiding the usual 10–20-year gap between updates allows the latest technologies to be continuously implemented. For providers, this means smaller (although more regular and numerous) contracts, reducing risk for both the providers and the TSOs.
The way forward
Vendor-agnostic modules and tools for system control applications will improve the management of increasing grid complexity, enabling more coordinated and efficient system operations. The position paper reflects a paradigm shift in how TSOs approach system operations, advocating for innovation, open architectures, and a collaborative path forward that ensures security, interoperability, and resilience across Europe’s energy landscape.
