The expert partner of the Solar Energy Association of Ukraine – Market Operator JSC – has presented an updated analytical study on the efficiency of battery energy storage systems (BESS) under changing market conditions in 2025.
The study focuses on BESS operation in the day-ahead market (DAM), where the key model remains price arbitrage – purchasing electricity during low-price periods and selling it during peak demand hours.
According to the modeling results for a 1 MW BESS with a capacity ranging from 1 to 4 MWh, increasing capacity to 3 MWh significantly improves operational efficiency. In particular, the number of operating hours increases almost threefold – from 410 to 1,195 hours per year – directly contributing to higher project profitability.
At the same time, further capacity expansion beyond 3 MWh does not provide a proportional economic effect. This indicates that an optimal balance between capital expenditures and revenues is achieved at this level.
Financial indicators confirm this trend:
- the payback period for a 1 MWh BESS is approximately 5 years;
- for systems with 3-4 MWh capacity, it decreases to 3.7-3.8 years;
- IRR, ROI, and NPV improve as capacity increases up to the optimal level.
The study also highlights battery degradation as an important factor: during operation, the average profit per hour gradually decreases, which should be taken into account in long-term project planning.
Read more in the analytical report “Energy Storage Systems: Operation in the Spot Market”: https://www.oree.com.ua/index.php/web/11618
Background: On the company’s website, in the “Market Participants” section under the “BESS” subsection, you can find all materials developed by Market Operator JSC on energy storage systems, including the opportunity to participate in testing the economic dispatch platform.