In Greece, grid-forming technology could help address voltage and stability challenges while creating new revenue opportunities for equipment and asset owners. At an energy conference in Athens on October 22, Miguel Ochoa, Europe Grid Director at SIGENERGY, said regulatory uncertainty was slowing the deployment of technologies designed to support electricity-system stability. The opportunity is emerging as developers and system operators respond to the technical limits of systems increasingly reliant on inverter-connected resources.
European electricity-network rules are being revised as regulators set more detailed technical requirements and system operators develop related procurement mechanisms. Equipment able to provide voltage support, synthetic inertia, reactive power and other stability services may gain commercial value beyond electricity sales and conventional balancing energy. Ochoa identified voltage regulation as a major challenge and pointed to grid-forming technology as a possible response.
The European Union is preparing changes to its Requirements for Generators network code, known as RfG 2.0, to update technical standards for modern generation and storage systems. For developers, engineering contractors and infrastructure investors in Southeast Europe, the changes could affect equipment procurement, grid-connection compliance and the development of new contractual revenue streams.
Grid stability requires services beyond electricity supply
Conventional electricity-market revenues are largely linked to energy delivered, available capacity and frequency-balancing services. Networks also require technical characteristics that cannot be measured simply by the amount of electricity sold. Voltage stability depends in part on connected equipment’s ability to absorb or inject reactive power, while frequency stability requires a rapid response when generation and consumption are out of balance.
Inertia and other fast-response characteristics help limit the rate of frequency change after a disturbance. Large power plants’ synchronous generators historically provided many of these functions, either naturally or through established controls. As systems rely more heavily on inverter-connected technologies, engineered control systems and appropriately designed equipment must increasingly supply those services.
Grid-forming inverters can contribute to this shift. Unlike conventional grid-following inverters, which typically synchronise with an existing grid-voltage waveform, grid-forming equipment can control its own voltage waveform and respond quickly to changing electrical conditions. Depending on design and available energy resources, it may support system strength, fast active-power response and local voltage stability.
Not every grid-forming device can provide every stability service, and products’ technical capabilities are not interchangeable. Even so, the technology creates opportunities for equipment manufacturers, engineering companies and electricity-asset owners. The services offered will depend on each installation’s design and capability.
European generator-code revision advances
The European Commission published a draft revision of the Requirements for Generators code on July 8, 2026, opening a consultation that closed on August 25. The proposed framework addresses the growing role of converter-connected generation, electricity storage and emerging technologies, including grid-forming capability. ENTSO-E, the European transmission-system association, had published detailed technical guidance on grid-forming requirements in November 2025.
The proposed code would strengthen the framework for defining how eligible installations must perform during disturbances and interact with electricity networks. The revised requirements have not yet entered into force. At the Athens conference, Ochoa indicated that the revised European regulation could be issued in English in February 2027, with other language versions following by May; this is a reported expectation, not a confirmed implementation date.
The timetable matters because developers are selecting equipment today for assets expected to operate for decades. If future technical requirements differ from the capabilities specified in current procurement contracts, projects could face additional engineering costs or equipment modifications. Conversely, installations designed with sufficiently advanced capabilities could be better positioned to meet future grid requirements.
The financial impact will depend on national implementation, how existing installations are treated and whether additional technical capabilities qualify for remuneration. Project developers, engineering contractors and infrastructure investors will therefore need to consider both future technical obligations and the potential for paid services.
Germany has introduced paid inertia procurement
The commercial potential is already evident in Germany. On January 22, 2026, the country’s transmission-system operators began market-based procurement of instantaneous reserve, designed to support local grid stability through a rapid response to active-power imbalances. Qualified resources, including suitable synchronous equipment and grid-forming converters, can provide defined inertia-related services.
Payment uses a fixed-price mechanism that takes into account product type, location and service availability. The framework differentiates between positive and negative response products, as well as different availability requirements. It demonstrates how technical system-stability functions can be turned into standardised commercial arrangements.
The German framework also illustrates the importance of an installation’s location and technical performance. An asset that supports local stability cannot necessarily provide the same value at every transmission-network connection point. Revenue depends on where the service is needed, which technical standards apply and how the system operator procures it.
Germany’s model does not mean comparable markets already operate across Southeast Europe. It does, however, provide a practical example for regulators and transmission operators considering their own procurement structures. The value of a service depends on the specific system need and the arrangements established to purchase it.
Southeast European operators face new engineering requirements
The issue is particularly relevant in Greece, Romania, Bulgaria, Croatia and Slovenia, where transmission and distribution operators must accommodate changing generation and consumption technologies. Technical standards and service procurement also matter in Serbia and Montenegro, where transmission requirements and regulatory alignment will affect the bankability of future investments. In each market, system operators will need to assess the implications of increasingly inverter-based resources.
In Greece, IPTO will need to assess how those resources affect system stability and grid operation. Romania’s Transelectrica faces similar questions about the technical characteristics and control capabilities of connected installations. In Croatia, HOPS and distribution-system operators will need to consider how advanced grid-support functions can be incorporated into operational and connection requirements.
Serbia’s legal framework already recognises non-frequency ancillary services and provides for their procurement through transparent, non-discriminatory and market-based procedures, subject to regulatory conditions and possible exceptions. This offers a potential regulatory foundation for more clearly defined technical services. However, legal recognition is not the same as an established procurement market that provides predictable revenues.
Commercial development requires system operators to identify specific needs, define technical products and put qualification and payment arrangements in place. The timing and structure of those steps will influence when stability services can generate revenue in individual markets. Germany’s framework provides an example, but does not establish that such arrangements exist across Southeast Europe.
Testing and certification will support service delivery
The shift changes the work required of equipment suppliers, independent engineers and project supervisors. Grid-forming performance cannot be established solely from a manufacturer’s marketing specifications; investors and system operators need evidence of how an installation performs under defined electrical conditions. Assessment may involve power-system studies, dynamic simulation models, protection coordination, inverter-control settings, site-acceptance tests and commissioning measurements.
For existing installations, determining whether advanced functions can be enabled may require detailed review of hardware capability, software, contractual warranties and grid-code obligations. The distinction between mandatory technical compliance and optional commercial services is important. A system operator may require specified reactive-power capability as a condition of connection, but that requirement does not automatically give the installation a right to additional revenue.
Commercial value arises when a qualifying service is separately remunerated under applicable rules or contracts. For lenders and investors, distinguishing compliance obligations from paid services helps prevent speculative stability-service revenues from being included prematurely in financial models. Independent technical assessment can also play a role when new services are introduced.
Advanced capability could affect project value
As grid-forming requirements develop, investors may need to distinguish between equipment that meets minimum connection obligations and installations able to provide additional contracted stability services. This could affect procurement strategies, acquisition due diligence and long-term operational planning. A project with documented grid-forming capability, validated dynamic models and suitable controls may be easier to adapt to changing technical standards.
Any valuation premium would depend on demonstrable avoided costs, greater operational certainty or additional contracted revenue. Developers must also account for the possibility that providing a stability service could impose operating restrictions or reduce the ability to earn revenue elsewhere. Contracts will therefore need to address availability, technical performance, service priority, liability and the interaction between different operating obligations.
Introducing advanced services could increase demand for specialist engineering, testing, independent certification and long-term technical supervision. These activities are commercially distinct from construction of conventional electricity-generation capacity. Their value will depend on the services required and the terms on which installations are contracted to provide them.
System-stability capability becomes an investment consideration
Emerging regulation indicates that electricity assets may increasingly be assessed on more than installed megawatts and expected generation. Their technical contribution to stable network operation could become a separate investment consideration. Commercial development will vary by country, depending on how quickly transmission operators identify system needs and establish procurement arrangements.
For Southeast European developers, an immediate priority is to understand future technical obligations before committing to long-term equipment contracts. Regulators and system operators must distinguish between services assets are required to provide for network security and additional services that warrant competitive remuneration. Germany’s paid inertia procurement demonstrates that such markets can operate, while the October discussions in Greece point to unresolved technical and regulatory arrangements in parts of Southeast Europe.
The commercial opportunity will depend on proving that an asset can provide a specific stability service at a location where it is needed, under a contract that makes the capability financially valuable. The developments also point to new sources of value beyond producing, storing and trading electricity, including securing electricity infrastructure for digital customers, monetising controllable consumption and delivering measurable technical services to system operators. The key investment distinction is whether these capabilities can be converted into enforceable contracts and predictable cash flows.
