CALL Energy, the renewable energy investment subsidiary of YEO Technology, and energy technology company Inavitas have signed an agreement to develop two battery energy storage projects with a combined capacity of 120MWh for Saves Enerji in what will become Türkiye’s first battery storage deployment under a build-operate-transfer Energy Service Company (ESCO) model.
The projects represent an investment of approximately US$40 million, including financing costs, and are scheduled to enter operation in 2027 before being transferred to Saves Enerji following a five-year operating period.
Türkiye’s First ESCO Model for Battery Storage
To execute the projects, CALL Energy and Inavitas established a dedicated project company named Solesco3 Renewable Energy Inc., with CALL Energy holding a 70% stake and Inavitas owning the remaining 30%.
Under the agreement, Solesco3 will provide project financing and oversee the turnkey delivery of battery energy storage systems, high-voltage substations, and grid connection infrastructure.
Following commissioning, Solesco3 will operate the facilities for five years before transferring ownership to Saves Enerji under the build-operate-transfer structure.
One of the projects will be integrated with the Çamlıca Hydroelectric Power Plant operated by Çamlıca Hidroelektrik A.Ş., while the second project will be developed as a standalone battery storage facility in Kayseri under Kayseri Müstakil Depolama A.Ş.
Locally Manufactured Battery Systems
The battery energy storage systems deployed in the projects will be manufactured locally in Istanbul by Reap Battery, YEO Technology’s battery manufacturing subsidiary.
Inavitas will provide the projects’ Power Conversion Systems (PCS), Energy Management Systems (EMS), and AI-powered energy trading platform, while YEO Technology will contribute engineering, equipment procurement, high-voltage substations, grid infrastructure, and system integration capabilities.
The partnership brings together investment development, project financing, engineering, local manufacturing, digital energy management, and long-term operations under a single integrated structure.
AI and Digital Energy Management at the Core
YEO Technology CEO Tolunay Yıldız said energy storage systems are becoming increasingly important for enabling the sustainable growth of renewable energy and improving grid flexibility.
“Through Türkiye’s first build-operate-transfer ESCO model for battery energy storage, we are not only delivering two important projects but also introducing a new model that combines financing, engineering, manufacturing, digital energy management, and long-term operations under one structure,” Yıldız said.
He added that the partnership combines CALL Energy’s investment and financing capabilities, YEO Technology’s engineering and integration expertise, Reap Battery’s manufacturing capabilities, and Inavitas’ digital energy technologies.
“We believe this US$40 million investment will make a significant contribution to Türkiye’s energy security, grid flexibility, and ambitions to become a regional hub for energy technologies,” Yıldız added.
Saves Enerji CEO İbrahim Akgün described the projects as an important milestone not only for the participating companies but also for Türkiye’s broader energy transition ambitions.
“The ability of leading companies to combine investment, financing, engineering, manufacturing, and technology capabilities around a common objective is one of the strongest aspects of this initiative,” Akgün said.
Inavitas Chairman Alper Terciyanlı emphasized the role of software and AI in maximizing the value of battery storage assets.
“Success in energy storage depends on combining robust hardware infrastructure with advanced energy management systems, power electronics, and data-driven optimization technologies,” Terciyanlı said.
He added that the company’s AI-powered energy trading platform and energy management technologies will enable the facilities to optimize operations based on market conditions and grid requirements.
Supporting Grid Flexibility and Renewable Integration
The projects are expected to improve renewable energy integration, strengthen energy security, increase grid flexibility, and support more efficient energy management within Türkiye’s electricity market.
The initiative also reflects the growing importance of battery storage infrastructure as countries seek to increase renewable energy penetration while maintaining grid stability and reliability.
Why It Matters
Battery storage is rapidly becoming one of the most critical components of modern energy infrastructure. By introducing Türkiye’s first ESCO-based build-operate-transfer model for energy storage, the project creates a new financing and deployment framework that could accelerate investment in grid-scale storage assets and support the country’s long-term renewable energy and energy security objectives.
