Construction of the country’s first enterprise for the automated production of vanadium redox flow batteries has begun in the Zagore – Elenino Industrial Zone. The investment will position Stara Zagora as a center for the development of long-duration energy storage technologies.
With a formal groundbreaking ceremony held on July 16, 2026, VESS officially launched the construction of its new high-tech plant in the Zagore – Elenino Industrial Zone.
The facility will be located on 6,928.70 sq. m of total built-up area and will be equipped with an automated production line for vanadium battery stacks – a key component of long-duration energy storage systems.
The ceremony brought together representatives of state and local authorities, the InvestBulgaria Agency, businesses, investors, designers, construction companies, and industrial partners of the project.
Among the official guests were Krasimir Yakimov, Deputy Minister of Innovation and Growth, Yulian Baldzhiev, Secretary General of the InvestBulgaria Agency, Radostin Tanev, Deputy Mayor of Stara Zagora Municipality, Radoslav Tanev, Executive Director of Zagore Industrial Zone AD, representatives of SUNOTEC, Solarhome, and the companies involved in the implementation of the investment.
The construction site was consecrated with a religious service for health and the successful completion of the project.
The start of a new industry for Bulgaria
In her keynote speech, Tsvetelina Borislavova, Executive Director of CSIF AD, as the general investor in the project, emphasized the strategic importance of the investment for Bulgaria and the European energy storage industry.
Today we mark the beginning of a new industry for Bulgaria – the first of its kind automated production of vanadium redox flow batteries.
She outlined the three main advantages of the technology: safety, long service life, and environmental sustainability.
Vanadium redox flow batteries use an aqueous electrolyte stored in separate tanks and circulated through electrochemical cells. Unlike systems based on flammable organic solvents, the aqueous electrolyte poses no risk of thermal runaway, fire, or explosion. The system’s power is determined by the number and type of battery stacks, while the capacity is determined by the amount of electrolyte, allowing the two characteristics to be scaled independently.
“These batteries are not intended for phones or cars. They are designed for solar and wind farms, power plants, industrial enterprises, and for stabilizing power grids,” Borislavova emphasized.
According to her, the project is much more than an investment in a new production facility:
“Today we are not just breaking ground. We are building a production facility that puts Bulgaria on the map of the European energy storage industry.”
The new plant will contribute to the creation of highly skilled jobs, technology transfer, and the development of high-value-added manufacturing in the region.
The broader concept envisions the creation of an integrated high-tech energy complex, including the production of vanadium batteries, photovoltaic modules, metal structures, logistics infrastructure, and recycling facilities. According to VESS, the battery plant alone is expected to provide over 120 jobs.
The State: A project with innovation and export potential
Deputy Minister of Innovation and Growth Krasimir Yakimov described the enterprise as a symbol of high technology and Bulgaria’s industrial potential.
“The project is a symbol of high innovation and industrial potential and has the opportunity to create highly skilled jobs.”
In his words, investments of this type have not only regional significance but also substantial potential for export and international competitiveness.
“We will continue to encourage projects with proven innovative and industrial potential – projects that create skilled employment and can compete successfully on international markets,” Yakimov stated.
He noted that the choice of Stara Zagora for the implementation of the investment was not accidental, as the region is in a process of economic and energy transformation.
“It is no coincidence that the investment is being realized right here, in Stara Zagora – a region that is confidently and successfully undergoing its economic transition.”
Stara Zagora Municipality: Cooperation between institutions and business yields real results
Deputy Mayor of Stara Zagora Municipality Radostin Tanev highlighted the project’s importance for the regional economy, employment, and the retention of qualified specialists.
“This investment shows what can be achieved when business, the state, the municipality, and the industrial zone work together.”
He emphasized that the implementation of high-tech projects is important not only for job creation but also for establishing Stara Zagora as a preferred location for strategic investors.
The Municipality and Zagore Industrial Zone will continue to assist in overcoming administrative and infrastructural challenges facing the project.
Congratulatory address from Minister Ivan Shishkov
On the occasion of the official start of construction, the Minister of Regional Development and Public Works Arch. Ivan Shishkov sent a congratulatory address to the organizers and guests of the ceremony.
In it, he described the construction of the plant as a significant step in the development of the high-tech industry and innovation in Bulgaria and emphasized that the investment combines technological progress, sustainability, and long-term vision.
“I am convinced that with the realization of this investment, Bulgaria is taking another step toward an economy based on knowledge, innovation, and clean technologies,” the congratulatory address states.
The Minister also highlighted the project’s role in creating high-value-added products, new opportunities for the industry, and prospects for Bulgarian specialists.
Why vanadium redox flow batteries are important
The expansion of production from renewable energy sources creates an increasing need for systems that can store electricity for many hours and supply it to the grid when needed.
VRFB technology is designed specifically for such applications – power grids, renewable energy farms, industrial enterprises, data centers, critical infrastructure, and autonomous energy systems.
VESS systems are designed for a service life of over 25–30 years, daily operation with multiple charge and discharge cycles, and capacity retention over time. The vanadium electrolyte can be recovered and reused, making it an asset with value even after the end of the service life of the other components.
The technology allows for independent sizing of power and energy capacity – a key advantage for large long-duration storage projects where standard battery configurations often require a significant expansion in the number of modules.
From symbolic groundbreaking to real production
The ceremony concluded with a symbolic groundbreaking, which officially marked the start of construction activities.
The new plant is part of the long-term strategy of VESS and the CSIF group to build a complete industrial ecosystem in the field of clean energy – from the production of photovoltaic modules and vanadium electrolyte to storage systems, metal structures, logistics, and recycling.
With the implementation of the project, Stara Zagora takes another step toward establishing itself as a regional center for high-tech manufacturing, sustainable energy solutions, and industrial investments with a long-term horizon.
