Yuso, a battery energy storage system optimizer based in Waregem, Belgium, has announced the start of operations of the Hertz 1 BESS facility in Kiisa, Estonia.  

Inaugurated on February 3rd, the 100-megawatt, 200-megawatt-hour system will soon expand services to include ancillary market operations as part of efforts to promote Baltic energy independence and grid stability. 

The Hertz 1 facility is the largest battery energy storage system currently operating in the Baltic region. It is co-owned by Mirova, Evecon, and Corsica Sole. Yuso serves as the route-to-market provider and commercial operator.

 Mirova is a global asset management company dedicated to sustainable investments and an affiliate of Natixis Investment Managers. Corsica Sole is a French independent solar power producer and European leader in energy storage, with more than 150MW ( peak ) of solar capacity in operation and 360MWh of storage. Evecon is a renewable energy developer focused on wind, solar, and energy storage projects in Estonia, Latvia, and Lithuania. 

"The Hertz 1&2 BESS come online at a pivotal moment for the Baltic energy system," says Yuso managing director Michel Verschuere. "As the region strengthens its energy independence following its joining the Continental Europe synchronous area, large-scale battery storage will play an essential role in maintaining grid stability and security of supply." 

Last October, the Baltic Storage Platform ( BSP ) joint venture secured €85.6 million ( US$100.74 million ) in financing from the European Bank for Reconstruction and Development ( EBRD ), Edmond de Rothschild Asset Management, and the Nordic Investment Bank ( NIB ) for its two battery energy storage projects, Hertz 1 and Hertz 2. A&O Shearman advised the lenders, with Ellex as legal counsel for Estonia. 

The transaction was the first project financing in the Baltics exclusively structured around the revenues generated by energy storage assets.  Both the EBRD and the NIB financings benefit from a first-loss risk cover from the European Union under its InvestEU programme.  

The two projects are located in Kiisa and Aruküla, both approximately 25 kilometres from the Estonian capital of Tallinn. With a combined capacity of 200MW of power and 400 MWh of storage capacity, Hertz 1 and Hertz 2 will form one of the largest battery complexes in continental Europe. Hertz 2 is currently under construction.