All construction works of the JSC Augstsprieguma tīkls (AST) development project "Estonia-Latvia third 330 kV interconnection" has been completed and the newly built 330 kV electricity transmission line from Estonia to Riga CHP-2 in Latvia has been put into operation. Electricity transmission line is planned to be fully commissioned by the middle of next year, but from the 1st of January, the line operation will be considered when calculating the transmission capacity allocated to the electricity market.

"Completion of this project is an important step in strengthening the energy independence of both Latvia and Baltic countries and an important step on the path to upcoming synchronization of electricity transmission networks with Europe in 2025. The construction of the new line will allow us to disconnect two existing aging interconnection lines between Latvia and Estonia for their reconstruction so that afterwards, the refurbished Estonia-Latvia interconnection would be fully prepared for the synchronous operation of Baltics with continental Europe ", the importance of the project is emphasized by Mr. Varis Boks, Chairman of the Board of AST.

Within the framework of the project, a 176 kilometres of 330 kV high-voltage electricity transmission line from Riga CHP-2 substation to the Estonian border was built in the territory of Latvia: 28 kilometres of  new electricity transmission line from the Estonian border to the existing transmission line corridor in the Rūjiena-Aloja section, then the line route continues along the existing 110 kV electricity transmission line corridor from Aloja, Limbaži and Skulte all the way to Saulkrasti. Further along, the line is located next to the upcoming Rail Baltica railway route. The project also included the expansion of the Riga CHP-2 substation, while the Estonian transmission system operator Elering has built a part of the electricity transmission line in Estonia from the country border up to the 330 kV substation in Kilingi-Nomme, and a new internal 330 kV electricity transmission line Harku-Sindi has been built in Estonia to provide the operational safety to the new interconnection.

In total, the costs of the 3rd interconnection project for the 330 kV electricity transmission line between the substations of Riga CHP-2 in Latvia and Kilingi-Nōmme in Estonia and for the internal Estonian 330 kV electricity transmission line Harku-Sindi are 170 million. EUR, of which 112 mln. EUR has been granted as a co-financing from the European Union's Connecting Europe Facility (CEF). In the territory of Latvia total costs of the 3rd interconnection project amounted for 80 mln. EUR, of which about 65% are the CEF funding.

The transmission capacity of the new line add approximately 600 MW, which will complement current Estonia-Latvia cross-section transmission capacity greatly. Until now, the existing transmission capacity of the interconnection was insufficient to ensure the required volume of electricity trade between Latvia and Estonia, which resulted in congestion and electricity price differences in certain hours of day. It is planned to eliminate the transmission capacity deficit in the Estonia-Latvia cross-section completely by year 2024, when the reconstruction activities on the Valmiera - Tartu and Valmiera - Tsirgulina lines will be finalised. Project "Third 330 kV interconnection between Estonia and Latvia" is also important contributor to the security of electricity supply and stable operation of the electricity transmission network both locally in Latvia and in the Baltics region in general.

Design and construction activities of the new electricity transmission line were performed by the general partnership "EE-LV Interconnection", which consists of SIA "Elko" from Latvia, Polish JSC "SELPOL" and Estonian JSC "LEONHARD WEISS ENERGY", while the civil works at the Riga CHP-2 substation were performed by JSC "Empower" branch in Latvia.

Work on the new electricity transmission line project has been started in year 2012 by submission of an application to the State Environmental Monitoring Bureau, in year 2014 an environmental impact assessment was launched and the public consultations on the project took place. Based on a joint application from AST and Elering, in October 2014 the project has been granted a 65% co-financing from the Connecting Europe Facility (CEF). In 2016, a tender was announced for design and construction works, and considering the significance of the project the Cabinet of Ministers of Latvia granted the status of the object of national interest to the project. The construction of the new electricity transmission line was started in early 2018 with the signing of a design and construction contract, the first pylon was raised in May 2019, while the construction of the line was completed in December 2020. The new line is planned to be fully commissioned by mid-2021.