Axpo, Advance Green Energy sign long-term hedging deal for Bulgarian BESS

Swiss energy group Axpo has signed a long-term financial hedging agreement with Bulgaria-based Advance Green Energy to secure market revenues for one of Bulgaria’s largest operational battery energy storage systems (BESS), the company said. 

The agreement covers the 124 MW / 496.2 MWh battery facility at the Balkan Industrial Park near Lovech, northeast of Sofia, providing guaranteed revenue streams for energy arbitrage and strengthening the project’s long-term profitability. Axpo said the arrangement will play a key role in supporting grid stability and renewable integration in the region’s power markets.

Exact terms or dollar figures were not provided.

The company added that the agreement builds on its expansion into energy storage markets, following similar activity in Poland. 

“Through this collaboration we are reaffirming our commitment to delivering innovative solutions that enable the growth of renewable energy and energy storage in emerging markets,” said Vasilis Machias, managing director of Axpo Greece. 

“This agreement reflects the shared vision between Axpo and Advance Green Energy to advance the energy transition in Bulgaria and the wider region.”

Georgi Domuschiev, the chairman of the board of directors of Advance Green Energy added that the company sees itself as a renewable energy leader in Bulgaria. 

“Partnering with Axpo on this long-term agreement validates our vision as a renewable energy leader in Bulgaria,” Domuschiev said. 

“The deal provides the financial certainty we need to continue investing in grid stability and renewable integration, while serving as a blueprint for similar projects in the region.”

According to Axpo, the Lovech BESS “remains the largest battery energy storage system in the Balkans” since its energization in May 2025. Advance Green Energy invested 147 million levs (USD 85 million) in the project, though the country now uses the Euro.

Last month, the Bulgarian government commissioned the 202 MW / 500 MWh Maritsa BESS, owned by ContourGlobal. 

Axpo, this week, also announced EUR 150 million (USD 176.7 million) in long-term debt financing via a so-called Schuldschein, a privately placed debt instrument. The company said more than 20 international investors participated in the transaction, which consists of two tranches with maturities of up to seven years, and allows for Axpo to make corporate investments in new and existing energy assets and facilities.