Blog Series: Battery Energy Storage Systems in Electricity Markets – Part 2

This article is the second part of a three-part blog series titled Battery Energy Storage Systems in Electricity Markets. In the first article, we explored the role of battery energy storage systems (BESS) in electricity markets. In this second part, we focus on what happens after the technical solution has been selected – in other words, how a battery energy storage system is prepared for participation in reserve markets. Participation in reserve markets starts with planning Implementing the technical solution is only the first step on the journey to electricity markets. Equally important is understanding what participation in reserve markets requires in practice. While the early stages of a project typically focus on equipment selection and control systems, preparing a BESS for market participation requires careful planning, interpretation of technical requirements and close cooperation between all stakeholders. Fingrid emphasises the importance of early project planning in its guidance – and for good reason. From the outset, it is essential to assess which reserve products the asset is suitable for and what technical requirements each product imposes. In Finland, reserve markets include FFR, FCR-D, FCR-N, aFRR and mFRR, each with its own requirements for response time, control accuracy and availability. Not every battery system is capable of participating in every reserve product without further system optimisation. The decisions made during this stage have a significant impact on the rest of the project. For example, some battery systems can provide frequency-controlled response independently (typically a C/D-type solution), while others require an external controller before they respond at all (generally referred to as B-type systems). Between these are solutions that meet some, but not all, market requirements. Understanding these differences during the planning phase helps avoid costly surprises later in the project. Market access is more than a technical challenge Technical performance alone is not enough. Communication systems and regulatory requirements must also be considered. For example, NC ER requirements do not apply to B-type facilities, which may simplify implementation. Nevertheless, reliable real-time data exchange remains a fundamental requirement for participation in reserve markets. The system must be able to communicate reliably with both Fingrid and other market participants. Once the technical implementation and market suitability have been evaluated, the project moves on to prequalification testing. This is where it becomes clear whether the system actually performs in accordance with the required specifications. The reserve provider is responsible for conducting the tests, while Fingrid reserves the right to monitor them. These tests are far more than a formality — they are a critical step in validating the system's performance under practical operating conditions. Syncron Tech has supported customers in numerous prequalification testing projects. Our role is typically to ensure that all system functionalities — from control logic to communication interfaces — meet Fingrid's technical requirements. We also assist with the preparation of project documentation, which often proves to be a much larger task than initially expected. In practice, documentation and the integration of multiple systems frequently become the most time-consuming aspects of a project unless they are addressed early and supported by the right expertise. Successful market participation depends on the whole system It is equally important to understand how responsibilities are divided between the different parties involved. Although technical implementation and testing are often carried out together with specialist partners, the customer remains responsible for several key market participant obligations. These include signing reserve market agreements and defining the real-time data exchange and market messaging required as part of the Balance Responsible Party (BRP) framework. Only after these steps have been completed can the asset participate in reserve markets. Looking ahead, the role of the aFRR market is expected to continue growing. This will place increasing demands on system control and integration, as aFRR requires continuous and highly accurate automatic control. The ability of a battery energy storage system to participate in this market cannot be taken for granted — it requires the right system architecture and a well-designed control solution. Successful market entry ultimately depends on managing the project as a whole. The technical system, control, communications, testing and market processes form a chain in which every link must function reliably. When each element is carefully designed and implemented, a battery energy storage system becomes far more than a technical investment—it becomes an active participant in electricity markets. Fingrid has outlined the main stages of participation in the reserve markets in its process description. The process progresses through the Prerequisites, Prequalification Tests, System Work and Market Agreements, and Start of Bidding phases. Further information is available on Fingrid's website: How to participate in the reserve markets.

The energy sector is undergoing a major transformation, affecting energy production, energy storage and the management of energy systems. At the same time, the growth of renewable energy, electrification and the digitalisation of the energy system are creating new opportunities and needs for industry stakeholders. Energia 2026 once again brings energy sector professionals together to discuss current topics and future solutions. The event will take place on 20–22 October 2026 at the Tampere Sports and Expo Centre. Energy Expo is Finland’s leading energy industry event, bringing together energy and grid companies, industrial companies, large real estate sector stakeholders, as well as providers of energy technologies and services. The event covers topics including energy production and technologies, energy efficiency, and sustainable and smart energy solutions. Syncron Tech will be exhibiting at the event. You can find us at booth E820, where we will showcase solutions for the efficient control and management of renewable energy production and energy storage. We will discuss topics including power management, hybrid power plants, battery energy storage systems (BESS), and participation in energy markets. See you in Tampere!

As renewable energy production continues to grow, the efficient operation, maintenance and reliability of renewable energy facilities are becoming increasingly important. Käyttö & Kunnossapito 2026 brings together professionals from the operational phase of renewable energy production to network and discuss current industry topics. The event will take place on 2–3 September 2026 at Sokos Hotel Arina in Oulu. It begins with a networking dinner on Wednesday, 2 September, followed by the program on Thursday, 3 September. The program will focus on topics related to the operation and maintenance of wind and solar power plants as well as energy storage systems. Syncron Tech will be attending on both days – at the networking dinner on Wednesday and as an exhibitor on Thursday. Come visit us on Thursday in the exhibitor area at stand 2. We look forward to discussing smart solutions for renewable energy production and energy storage with you. See you there! Read more about Käyttö & Kunnossapito 2026 event here.

This article is the first part of a three-part blog series titled Battery Energy Storage Systems in Electricity Markets. The series explores how battery energy storage systems (BESS) operate in electricity markets, how they are integrated into reserve markets, and practical experiences from testing different ancillary services. In this first part, we focus on BESS from the perspective of electricity markets. Battery energy storage systems from an electricity market perspective Battery energy storage systems have become a key element in the ongoing transformation of electricity markets. Flexibility has become one of the most important characteristics of modern power systems. However, in practice, flexibility is not achieved through battery capacity alone. The critical factor is how the entire system is designed, controlled, and integrated into both the power system and electricity markets. This is where differences between BESS solutions become evident. At Syncron Tech, we have been involved in several battery energy storage projects in recent years. Based on our experience, the technical implementation plays a decisive role in project success. A common assumption is that a battery system can be directly connected to Fingrid’s reserve markets. In practice, the situation is more complex. There are significant differences between battery technologies and system implementations, for example in response times, control accuracy, and controllability. These characteristics ultimately determine whether the system meets market requirements and passes the required compliance testing. These challenges typically become visible during the grid compliance assessment process. This is not about a single requirement, but a combination of several aspects, including frequency and voltage support, measurement systems, protection schemes, and real-time communication. In many projects, it becomes clear at this stage that inverter-level control alone may not be sufficient. PPC as the bridge to electricity markets At this point, the control system becomes essential, particularly the Power Plant Controller (PPC). Centralized plant-level control enables the entire facility to be operated as a single coordinated system, implementing the control logic required by Fingrid and adapting to the requirements of different reserve markets. It also enables reactive power capability at the point of connection and supports required market communication interfaces. In practice, the PPC acts as a bridge between the technical system and electricity markets. The overall solution matters Recently, attention has also been drawn to the practical operation of battery systems. Reserve markets require fast power changes, which means continuous switching between charging and discharging and steep ramp rates. However, overly aggressive control strategies can accelerate battery degradation, reduce performance, and in the worst case impact warranty conditions. Therefore, a balance must be found between market optimization and technical lifetime performance. In many projects, a workable approach has been to keep the core BESS delivery relatively lean, while complementing the overall system with a dedicated PPC solution. This provides the necessary flexibility without overengineering the entire installation. At the same time, it improves interoperability between different stakeholders, such as traders, control centers, and grid operators. It is also important to note that grid code requirements are extensive, and it is not always practical to implement everything in-house. Competent partners therefore play a key role throughout different phases of the project. When system architecture, control strategy, and market requirements are considered as a whole, a battery energy storage system becomes more than just a physical asset — it becomes an active and value-generating part of the power system.

Vaasa EnergyWeek brings together energy industry professionals from around the world to exchange the latest insights, network, and discuss future solutions for the industry. The event is scheduled for March 16–19, 2026, at Vaasa City Hall. Each day will focus on a specific theme: Energy & Climate, Wind & Renewable Energy, Energy Storage, and Clean Gas Energy. The program will also highlight key topics such as digitalization, the circular economy, business and innovation. The week begins with a seminar, Energia- ja ilmastoseminaari (in Finnish), while the rest of the program will be mainly in English. Exhibitors will open their booths on the second day of the event. Syncron Tech supports the energy industry's transformation by providing key solutions for project developers. Our solutions cover planning, operational phases, and asset condition management. Hybrid solutions for renewable energy production are becoming increasingly important as transmission grid capacity is limited and new connections are not always available. Efficient hybrid solutions can still be implemented within existing grid connections. Visit us at booth B12–13, where Lasse Kankainen and Jussi Eskelinen will be present from Tuesday to Thursday. We will be pleased to discuss how we can support your projects, whether they involve wind, solar, or energy storage. We are also glad to share our perspective on the potential of flexible electricity connections as part of a comprehensive solution, especially when production and consumption converge at a connection point, and the overall system requires an intelligent power management solution – such as in industrial facilities or data centers. See you at the event! Vaasa EnergyWeek provides an excellent opportunity to stay informed about the latest developments in the energy industry and to network with industry professionals. Read more about Vaasa EnergyWeek 2026 here.

Did you know that starting January 1, 2026, an amendment to the Electricity Market Act will enable flexible electricity connections? The power system is undergoing rapid transformation. Industrial electrification, renewable energy generation, energy storage and new high-demand loads are driving a rapid increase in connection capacity requirements, while in many areas the grid is already operating near its limits. Flexible electricity connections provide a solution in situations where full connection capacity is not immediately available. They enable investments and operations to commence without long waiting periods for grid reinforcement. In practice, however, a flexible connection always requires a reliable power management system.

The electricity market is middle of a major transformation. Moving to a quarter hour balancing period has changed the way production and consumption are managed. As a result, forecasting accuracy and fast response times are now more important than ever.

As we wrote in our previous blog on hybrid power plants, a change was made to the Electricity Market Act in the spring of 2025, allowing interconnected production units and energy storage systems to be connected to the power grid via a shared connection line, even if they are located on different properties. This change, along with other recent changes to the Electricity Market Act and developments in the market, reduces the costs of grid connection. These changes also help enable a more flexible electricity grid, where hybrid power plants can operate as an integral part of the overall energy system. The development of the power system will continue to be wide-ranging, and the size of generation plants is also expected to increase. In our view, future systems will increasingly involve energy production systems above 110 kV, so it is important that grid permits and bureaucracy do not become obstacles to large-scale projects.

Syncron Tech will be participating in the Käyttö ja kunnossapito -ajankohtaispäivät organized by Finnish Renewables on September 3–4 in Oulu!