Tetas, an energy infrastructure development and maintenance company, is carrying out construction and grid connection works for a battery energy storage system in Rietavas under a contract with MT Group. Lithuania’s first four-hour energy storage project will significantly enhance the flexibility and reliability of the electricity transmission network and enable further integration of renewable energy in the country.
MT Group is delivering the project as the general contractor, with Tetas responsible for the main construction and grid connection works under the signed agreement. The battery energy storage system, with a power capacity of 35 megawatts (MW) and an energy storage capacity of 140 megawatt-hours (MWh), will be connected to Litgrid’s 110 kV high-voltage substation, ensuring efficient operation and integration into the electricity transmission network.
“Battery energy storage systems are a key component of modern energy infrastructure, supporting grid flexibility and sustainable development. We are pleased to work with trusted partners on this project in Rietavas. Our strong team and experienced contractors enable us to ensure the highest standards of workmanship and the smooth delivery of this strategically important facility,” says Dr Kristina Norvaišienė, Executive Director of MT Group.
“We bring substantial expertise to this project. A few years ago, we took part in the construction of the Energy cells energy storage system—the first in the region and, at the time, the largest in Europe. This experience gives us the confidence to deliver the full scope of construction and grid connection works for the battery energy storage system in Rietavas. The project will strengthen Lithuania’s energy security and mark a new stage in the development of energy storage in the country,” says Ovidijus Martinonis, CEO of Tetas.
Under the contract, Tetas is installing the switchyard at the Rietavas transformer substation, laying a 110 kV cable between the Rietavas and Drobstai transformer substations, and carrying out construction and grid connection works for the battery storage facility. The project is scheduled for completion in the first half of 2027. Once operational, the facility will provide frequency control and balancing reserves, support cross-border integration, and participate in the Baltic and Nord Pool balancing markets.
Rietavas is one of several battery energy storage projects currently being delivered by Tetas. The company is also carrying out construction and grid connection works for a 56 MW / 168 MWh battery energy storage system in Raseiniai District, where MT Group is likewise acting as the general contractor.
