The newly commissioned Battery Energy Storage System (BESS) at EVN Naturkraft’s hybrid park in Trumau is now fully operational, marking a decisive advancement in the integration of renewable energy and storage technologies. Situated alongside the 10 MW photovoltaic plant in Trumau and interconnected with the 16 MW wind farm in Tattendorf, the storage system enables surplus electricity to be efficiently stored and reintroduced into the grid as required. With this development, the hybrid park now supplies clean energy for approximately 13,000 households while simultaneously strengthening grid stability and flexibility.
At the heart of this innovation is the BESS, comprising an SMA MVPS SKID and a Hithium battery container with a rated output of 3.4 MW and a capacity of 6.8 MWh. This installation corresponds to the storage potential of roughly 500 household battery systems and transforms the Trumau site into a pioneering “super-hybrid park.” By capturing excess energy and discharging it when needed, the batteries provide a reliable mechanism to balance supply and demand, thereby mitigating the volatility inherent in renewable generation. A particular advantage lies in the system’s ability to deliver balancing services, including Frequency Containment Reserve (FCR), automatic Frequency Restoration Reserve (aFRR), and manual Frequency Restoration Reserve (mFRR). These functions directly contribute to the stability of the Austrian power grid, ensuring that renewable energy can be deployed with greater consistency and reliability.
The strategic integration of the BESS into the hybrid park also opens new opportunities for energy market participation. Our flexibility management platform, CyberNoc, plays a central role in this process by enabling the aggregation and optimization of the hybrid assets for multi-marketing. Through this digital infrastructure, the storage system is seamlessly connected to both balancing and wholesale energy markets, allowing EVN to unlock new revenue streams while reinforcing system resilience. This combination of technical innovation and digital market access demonstrates how storage is becoming a cornerstone of modern energy systems, ensuring that renewable generation can be both economically viable and operationally sustainable.
The operational strategy of the Trumau BESS is designed to maximize both flexibility and efficiency. While a portion of its daily cycles is dedicated to providing balancing services for the grid, another share is allocated to trading on day-ahead and intraday markets. On average, the batteries are expected to complete two cycles per day, with charging from the grid occurring only when the system is actively engaged in regulation reserve services. This approach ensures that the storage system functions as a stabilizing force rather than a net consumer, further strengthening its contribution to grid reliability.
The commissioning of the Trumau BESS therefore represents more than a technical milestone, it signals the emergence of a new model for hybrid energy systems in which renewable generation, storage capacity, and market integration are combined to deliver both environmental and economic value. By enhancing the capacity to balance fluctuations, optimize grid infrastructure, and capitalize on market opportunities, the project underscores the strategic importance of battery storage for the future of energy systems. EVN has already indicated that additional sites will be equipped with storage where system benefits can be maximized, reinforcing the role of batteries as a critical enabler of the energy transition.
📷 ©EVN / Nadine Studeny
