Lithuania’s electricity transmission system operator, Litgrid, has signed a contract for the design workk of the Harmony Link overland electricity interconnector with Poland. The appointed contractor will be responsible for preparing the main technical solutions and designing the key infrastructure elements of the interconnector on the Lithuanian side – a 220 kV transmission line and the Gižai substation.
“By signing the design services contract, we are launching an important stage in the implementation of the Harmony Link overland interconnector. We have been preparing responsibly for this step – in the autumn of 2024, we conducted market consultations, during which we discussed technical aspects with potential contractors and, based on the feedback received, refined the procurement documentation. In order to ensure faster project implementation, we are also carrying out territorial planning and environmental impact assessment procedures in parallel,” says Rokas Masiulis, CEO of Litgrid.
During the design phase, essential technical decisions will be made and the most important elements of the Harmony Link infrastructure in Lithuania will be designed – a 220 kV power transmission line and a 330 / 220 / 110 / 10 kV Gižai transformer substation. In addition, to ensure the timely acquisition of long-term supply equipment, technical specifications for autotransformers and shunt reactors will be prepared.
Litgrid signed a design services and construction works contract with the supplier consortium UAB Energetikos projektavimo institutas and UAB Ener-G Design, which won the public procurement tender. The contract value is EUR 2.2 million excluding VAT.
The design phase is expected to last 29 months, until all necessary construction permits are obtained. Project implementation supervision services will be provided until the completion of construction works.
To ensure a faster implementation process, territorial planning and environmental impact assessment procedures for the Harmony Link project are being carried out in parallel with the design activities. In March, Litgrid prepared the concept of the interconnection’s engineering infrastructure development plan and a Strategic Environmental Assessment (SEA) report.
The project partner – Poland’s electricity transmission system operator PSE – approved its financial investment decision for the construction of the overland section of the Harmony Link interconnector in December last year. In accordance with the cooperation agreement signed by both operators, Litgrid’s financial investment decision, adopted in September 2024, also came into effect at the same time.
The Harmony Link overland interconnector in Lithuania is planned within the territories of Vilkaviškis, Kalvarija and Marijampolė municipalities. The project consists of the construction of a new double-circuit 220 kV alternating current transmission line between Ełk Bis (Poland) and the planned Gižai substation in Vilkaviškis District, as well as the construction of the Norki and Wigry substations and the reconstruction of the existing 220 kV Ostrołęka–Ełk Bis transmission line in Poland.
Construction works for the Harmony Link interconnector are scheduled to commence in the second quarter of 2027. The interconnection is planned to be commissioned in 2030.
The Harmony Link project has been granted the status of a project of special national importance.
Lithuania and Poland already have an existing overland interconnector – LitPol Link – which was instrumental in synchronising the Baltic States’ electricity systems with the Continental European grid.
The Harmony Link project is co-financed by the European Union through the Connecting Europe Facility, aiming to strengthen the country’s energy security, integrate a greater share of renewable energy sources, and ensure sufficient capacity for commercial electricity trade after the synchronisation of the Baltic States’ grids with Continental Europe.
Source: Litgrid
