Production has begun at a battery energy storage system (BESS) factory designated as a project of strategic importance by the European Commission (EC) due to its use of local supply chains.
An inauguration event was held earlier this month (10 October) for the factory, at Hemus High-Tech Industrial Park, around 5km from Sofia, the capital of Bulgaria.
Built by Bulgarian renewable energy system and microgrid controls company International Power Systems (IPS), all components of the BESS units, except the lithium iron phosphate (LFP) battery cells, are designed and manufactured by IPS in-house.
Former president of Bulgaria Rosen Plevneliev, current deputy prime minister Tomsilave Donchev and Sofia’s mayor Vassil Terziev ceremonially cut the ribbon to open the gigafactory.
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The factory, which will begin work with an initial 1.5GWh annual production capacity at the first phase, ‘X1’, will ramp to 3GWh by the end of the year with the addition of ‘X2’. The total capacity will be ramped up to 5GWh by Q2 2026.
It will make IPS’s Exeron battery storage product range. The range’s flagship product is the Exeron X-BESS 8, a system in modular plug-n-play enclosures with up to 8.1MWh capacity in a 20-foot container, equipped with 4MW liquid-cooled power conversion system (PCS) per unit and with a claimed 99.5% inverter efficiency.
X-BESS 8 features 314Ah LFP cells, capable of up to 12,000 cycles, but the company claims its real strength lies in its having engineered each subsystem component in-house, including mechanical and electrical design and embedded firmware.
IPS is currently selling X-BESS 8 predecessor models, in 5MWh and 6MWh configurations. The company showcased the range, including its ‘Made in Europe’ domestic supply chain credentials, at Intersolar Europe / ees Europe in Germany, earlier this year.
The X-BESS manufacturing project was deemed to be of strategic importance for the European Union (EU) under its regulation for the development of net zero emissions technologies, the Net-Zero Industry Act (NZIA).
The Bulgarian minister of economy and industry Peter Dilov held a meeting with IPS executive director Aleksandar Rangelov in July to discuss the project and noted that the battery energy storage tech development is included as a priority action in the country’s sustainable energy production roadmap.
“The project is a major step towards including Bulgaria among European producers of ecological technologies and the application of high-tech solutions to overcome climate change,” Dilov said in July.
“We believe that this project has justly taken a key place in the clean technology value chain. This is a step forward for Bulgaria and our participation in European and global industry for energy transformation.”
Lyten will begin delivering Northvolt BESS units by end of year
In other BESS manufacturing news from Central and Eastern Europe, US-headquartered lithium-sulfur battery startup Lyten Energy has closed its acquisition of the Northvolt Dwa factory in Poland.
Lyten Energy’s intended purchase of manufacturing assets from fallen Swedish battery and BESS manufacturing hope Northvolt was announced in July. Lyten said it would restart production immediately at Northvolt Dwa, in Gdańsk, on the closing of the transaction.
In reporting the closing last week (16 October), Lyten confirmed that it would begin the restart process immediately and could begin the first customer deliveries before the end of 2025.
The 25,000 square metre factory and accompanying R&D facility opened in 2023. In its present configuration, the renewable energy-powered factory could ramp up to 6GWh annual production capacity, while Lyten claims it can further double in annual capacity to 12GWh in future.
The first products to roll off the line when Northvolt Dwa reopens will be Northvolt’s Voltpack Mobile System, aimed at applications including temporary power supply and commercial and industrial (C&I) energy storage.
California-headquartered Lyten Energy is commercialising its proprietary lithium-sulfur technology for stationary storage applications and hopes to achieve mass production in the near future. However, as discussed by the company’s chief business officer (CBO) Keith Norman in an interview with ESN Premium, Lyten will initially focus on delivering lithium-ion (Li-ion) BESS products, targeting customers in Europe and international markets.
After its Northvolt Dwa deal was announced, Lyten went on to successfully bid for most of Northvolt’s other assets, including Northvolt Ett, the flagship gigafactory; Northvolt Labs, which is also in Sweden; the Northvolt Drei gigafactory in Germany; and all remaining Northvolt IP. Lyten CEO Dan Cook said however in a press conference this summer that the buyer would take a cautious approach to ramping up, expanding production capacity one gigawatt-hour at a time.
The European startup’s high-profile bankruptcy proceedings began near the end of 2024 as it filed for Chapter 11 bankruptcy protection in the US.
