Estonian electricity transmission system operator (TSO) Elering and Latvian TSO Augstsprieguma tīkls (AST) have agreed to develop a new electricity interconnection between Estonia and Latvia.

Elering and AST have signed a memorandum of understanding (MoU), under which they will jointly develop the fourth Estonian-Latvian electricity interconnection.

The new interconnection is expected to enhance the transmission capacity between Estonia and Latvia, enabling the development of renewable energy sources in the Baltic Sea region.

The project is planned to be built in hybrid mode, where it would also potentially connect the renewable energy standard (RES) offshore and onshore production to the electricity systems.

It also provides opportunities to receive a larger amount of RES into the Estonian and Latvian electricity networks, helping the countries achieve their climate goals.

The exact location and other technical details of the interconnection project will be finalised in the later stages.

It is estimated to have a capacity of around 1,000MW, based on the previous evaluation and technical analysis, and is expected to be completed by 2035.

The planned interconnection project is expected to increase the supply security, along with the security and stability of the electricity systems.

AST board member Arnis Daugulis said: “The new interconnection is an important step of transmission capacity increase between Estonia and Latvia, which is essential for the development of renewable energy sources (RES) in Latvia and Estonia, both onshore and offshore.

“We see this cooperation as the first step towards the creation of interconnected hybrid transmission grid in the Baltic Sea, thereby contributing to the goals of decarbonisation and RES development for the whole Baltic Sea region.”

Elering and AST have agreed to work together on the preparatory activities, including several studies, which are essential for making future investment decisions on the development.

The two TSOs are expected to receive co-financing from the European Union (EU) CEF grants for the evaluation and construction of the interconnection.

The fourth interconnection follows the Third Estonian-Latvian electricity interconnection, which was constructed and started operation in 2020.

The remaining two interconnections, Valmiera-Tartu and Valmiera-Tsirguliina, are currently under construction as a part of the Baltic States synchronisation project.

Elering board chairman Kalle Kilk said: “Elering is exploring the possibilities of establishing a new connection between Estonia and Latvia from Saaremaa to Kuramaa in Latvia.

“Establishing a new connection to Latvia via Saaremaa would enable the most additional capacity between the two countries to be obtained at the lowest cost.”