Battery energy storage systems can play a key role in stabilising the electricity grid, but the way they are operated has a significant impact on both battery degradation and profitability. This is the conclusion of new research from Chalmers University of Technology.
In her licentiate thesis, Meryem Ahouad, a doctoral researcher at the Division of Electric Power Engineering, investigated how large-scale battery energy storage systems perform when providing Frequency Containment Reserve (FCR) services in the Nordic power system.
By combining advanced simulation models with experimental ageing data, she evaluated both battery degradation and economic performance under realistic operating conditions.
“My main takeaway is that battery energy storage systems can play a key role in supporting a renewable electricity system, but their long-term value depends on understanding and balancing operational performance, battery ageing and economic returns,” says Meryem Ahouad.
The results show that batteries providing upward frequency regulation experience the highest degradation, primarily because they spend long periods at a high state of charge. At the same time, the most profitable strategy was to combine different frequency control services. A battery system with a capacity of 1 MW/1 MWh could generate an annual net profit of approximately SEK 1.1 million under such a configuration. The study also shows that different reserve products affect battery degradation in different ways, mainly through their impact on the battery’s state of charge.
“For companies and organisations investing in battery energy storage systems, the findings show that carefully selecting operating strategies and reserve markets can significantly improve both profitability and asset lifetime,” she says.
The research provides new insights into how battery storage can support future electricity systems with growing shares of renewable energy while balancing technical performance, battery lifetime and economic viability.
The research was carried out at the Division of Electric Power Engineering at Chalmers University of Technology.
The supervisors were Evelina Wikner, Assistant Professor in Electric Power Engineering, and Torbjörn Thiringer, Professor of Electric Power Engineering. The project was funded by the Swedish Electricity Storage and Balancing Centre (SESBC).
Related:
The licentiate thesis ▶ Performance Evaluation of Battery-Based Energy Storages for Various Duties
▶ The division for Electric Power Engineering
▶ Swedish Electricity Storage and Balancing Centre – SESBC
▶ Performance evaluation of battery-based energy storages for various duties, in terms of power, energy and environmental impact Forskningsprojekt, 2022 – 2026
- Doctoral Student, Electric Power Engineering, Electrical Engineering
- Assistant Professor, Electric Power Engineering, Electrical Engineering
- Full Professor, Electric Power Engineering, Electrical Engineering
