Wärtsilä has agreed to establish a joint venture with the German company RCT Solutions GmbH for its global Energy Storage business. Ownership of the joint venture will be split between RCT Solutions (50%) and Wärtsilä (50%). The joint venture may later take on new investors, which could reduce the stakes of the original owners.
The plan is for the joint venture to include Wärtsilä’s Energy Storage business, which is Wärtsilä’s smallest business segment and is currently reported as a separate segment. Energy Storage has approximately 480 employees globally and recorded a turnover of 694 million euros and a profitability of 3.3 percent in 2025. Wärtsilä would transfer net assets to the joint venture representing less than 5 percent of Wärtsilä’s total net assets.
The Energy Storage business supports the decarbonisation of the energy sector and provides scalable, integrated battery-based energy storage systems (BESS) and their optimization for power plants. At the core of the solutions are proven reliability, flexibility, and safety. The portfolio includes high-performance hardware, intelligent control and optimization software, as well as full-service lifecycle support.
RCT Solutions GmbH is a German specialist company founded in 2012 with strong international experience in solar power and battery-based energy storage systems. RCT Solutions brings strong market expertise, execution capability, knowledge of global supply chains, and the opportunity to implement vertical integration in the near future through an ongoing production project in the United States. The company has led the design and establishment of several battery and solar-focused production facilities globally, and one of the RCT companies has served as a key supplier for Wärtsilä’s Energy Storage business for years.
The joint venture is expected to be completed in the third quarter of 2026, subject to regulatory and other customary conditions and approvals, and once the joint venture’s financing is secured. As a result of the agreement, Wärtsilä Energy Storage will cease to exist as a separate reporting segment in the second quarter of 2026. Simultaneously, its financial targets will end and demand guidance will be discontinued. The agreement is not expected to have a significant impact on Wärtsilä’s results at the time of the joint venture’s completion. The joint venture will benefit from project guarantees already granted by Wärtsilä for ongoing projects.
The joint venture is expected to be loss-making in 2026 due to recent low order volumes and the costs of future transformation measures, which mainly consist of the write-down of capitalized research and development expenditures. The impact on Wärtsilä’s full-year 2026 operating result is estimated to be between -40 and -50 million euros, depending on the exact timing of the joint venture’s completion.
The joint venture is expected to reach profitability moving towards the end of 2027.
Until the completion date of the joint venture, the Energy Storage business will be reported as discontinued operations and assets held for sale. From the date of the joint venture’s establishment, Wärtsilä will report its share of the joint venture’s result in the “Other business” category under the item “Share of results of associates and joint ventures”.
Related financial information 2025
| EURm in 2025 | Wärtsilä | Energy Storage |
|---|---|---|
| Order book | 8,248 | 719 (8.7% of Wärtsilä) |
| Net sales | 6,914 | 694 (10.0% of Wärtsilä) |
| Operating result | 833 | 23 (2.8% of Wärtsilä) |
| Operating result as a percentage of net sales | 12.1 | 3.3 |