Sofia, Bulgaria, July 28, 2025 — SUNOTEC, a leading European integrated solutions provider in the solar energy sector, and Sungrow, a global leader in PV inverters and energy storage systems, have officially signed a strategic agreement to deploy 2.4 GWh of Battery Energy Storage Systems (BESS) across multiple solar power projects in Europe. This agreement marks Sungrow’s first entry into the Bulgarian energy storage market and represents a milestone for driving the energy transition in Southeast Europe.
Project Scale and Coverage
The upcoming portfolio includes multiple large-scale projects distributed throughout Bulgaria, with several projects receiving funding support from Bulgaria’s RESTORE national support program. The RESTORE program was approved by Bulgaria’s Ministry of Energy in April 2025 with a total investment of 1.15 billion leva (approximately $675 million), supporting 82 standalone energy storage projects with a combined capacity of 9.7 GWh, as part of the EU’s Recovery and Resilience Facility initiative.
Under the agreement, Sungrow will supply SUNOTEC with its industry-leading PowerTitan 2.0 battery energy storage system. PowerTitan 2.0 is a professional liquid-cooled energy storage system featuring 314Ah high-capacity cells, integrating 5 MWh battery capacity and a 2.5 MW Power Conversion System (PCS) within a standard 20-foot container. Additionally, Sungrow’s SG350HX-20 string inverter and Medium Voltage Solution (MVS) will be used for hybrid solar-plus-storage projects within the portfolio.
Technical Advantages and Safety Assurance
PowerTitan 2.0 integrates Sungrow’s core capabilities in power electronics, electrochemistry, and grid support technologies. The system is equipped with Stem Cell Grid Tech, enabling advanced features including enhanced high and low voltage ride-through, multi-level broadband oscillation suppression, flexible inertia support, microsecond-level voltage construction, and gigawatt-level black start capabilities.
Large-scale testing conducted under DNV supervision has proven that even in extreme fault scenarios where fire occurs in a single container, adjacent containers maintain temperatures below critical levels (maximum 84°C), preventing fire spread. The system employs artificial intelligence for real-time, high-precision cell monitoring, detecting anomalies early and providing warnings to effectively prevent thermal runaway. Sungrow maintains a zero-fire incident safety record.
Market Significance and Strategic Value
Kaloyan Velichkov, Founder and CEO of SUNOTEC, stated: “The global energy transition depends not only on how much renewable power we produce, but on how intelligently we manage and store it. This partnership with Sungrow reflects our shared ambition to lead the next chapter of clean energy—by building resilient, storage-enabled infrastructure that brings stability, sustainability, and scale to markets across Europe and beyond.”
Anastasios Gkinis, Regional Director of Sungrow for CEE, SEE & CIS, said: “This collaboration with SUNOTEC is a cornerstone of our mission to accelerate clean energy deployment in Bulgaria and across Europe. Combining Sungrow’s cutting-edge energy storage technology with SUNOTEC’s execution excellence, we create a powerful force to redefine the energy landscape in Bulgaria and support the region’s transition to a sustainable energy future.”
Advancing Regional Energy Transition
The 2.4 GWh energy storage capacity will support grid stability, enable better renewable energy integration, and enhance the reliability of solar parks developed and constructed by SUNOTEC throughout Bulgaria and wider Europe. Following the success of the first RESTORE round, Bulgaria’s Ministry of Energy launched a second consultation round in August 2025, planning to support an additional 1.9 GWh of standalone storage capacity, demonstrating the country’s continued commitment to energy storage infrastructure development.
As of 2024, Sungrow has delivered 25-30 GWh of energy storage systems globally, with over 9 GWh of storage capacity installed in Europe. Landmark projects include the UK’s Bramley 100 MW/331 MWh energy storage project (Europe’s first PowerTitan 2.0 deployment, operational since February 2025), and the 7.8 GWh global largest energy storage project in partnership with ACWA Power in Saudi Arabia (under construction).
As Europe’s renewable energy penetration continues to rise, large-scale energy storage systems have become crucial for balancing grid supply and demand, reducing curtailment, and providing ancillary services. The collaboration between SUNOTEC and Sungrow not only sets a benchmark for energy storage development in Bulgaria but also provides a replicable success model for energy infrastructure modernization and clean energy transition across the entire Southeast European region.
