The Helsinki 400 kilovolt power cable connection

Environmental Survey
Project details
Project type: Cable
Project state: Building
Location: Helsinki
Length: 12 kilometres

Fingrid has been working in close cooperation with the City of Helsinki and Helen Electricity Network to design Finland’s first 400-kilovolt cable link in the main grid. The new link will be built in Helsinki to cater for the increase in electricity consumption in the Helsinki metropolitan area and promote the green transition. Implementation will begin next year, and the connection is planned for completion in 2026.

Project status

The project is currently in the building phase. A tentative route for Helsinki’s new underground cable has been selected in March 2022. You will find more information about the project and the selected route in the section "General planning". 

Project background

The City of Helsinki, Helen Electricity Network Ltd and Fingrid Oyj (the parties) have jointly investigated the overall technical solution in the electricity distribution grid and main grid required for the realization of Western boulevard city. From an overall economic point of view, a joint solution between the three operators is the most profitable option.

An agreement on general planning between the parties was signed in December 2020. The agreement initiates the general planning phase of the project, which will specify the technical design, costs and schedule of all parties.

Within the general planning phase, Fingrid Oyj performed the general planning for a new 400 kilovolt power cable connection between Länsisalmi in Vantaa and Viikinmäki in Helsinki. This new power cable connection will enable the City of Helsinki to release land for the construction of Western boulevard city. The new power cable connection will strengthen Helsinki’s electric grid and support the carbon neutrality goals of Helsinki and Helen Ltd. It will contribute to the transition to carbon-neutral energy generation by 2030.

Project schedule

Fingrid will construct the 400 kV cable connection tentatively by the end of 2026.

Press Releases and articles:


Stage related info

General planning

During general planning, a route and construction plan for the 400 kV power cable connection, an expropriation plan for the right of use to the 400 kV cable route, an extension of the Länsisalmi substation, the Vanhakaupunki substation and a route study for transformer transport were planned.

News 2022

In December 2022, Fingrid decided to invest more than EUR 100 million in the construction of the cable connection.

Energy Authority has granted (16.5.) Fingrid Oyj a project permit for the construction of a 400 kV power line between Helsinki and Vantaa (decision Dnro 1222/040101/2022).

The tentative route of the new underground cable has been decided. Based on surveys and negotiations with authorities, the planners consider the best option to be a route through areas owned by the cities, from the Viikinranta energy block via Viikki’s fields, Hallainvuori, Ring I and the Kivikko Sports Park to Länsisalmi. The final route of the underground cable will be specified during the construction planning phase to be launched this year. For more information: Report on the planning phase (in Finnish)
Press release: Fingrid chooses tentative route for Helsinki’s new underground cable

The field surveys of the project will start on 28 March 2022 from the Viikinranta energy block area. The field surveys will continue until the end of June 2022.

News 2021

On 25 November 2021, the National Land Survey of Finland granted Fingrid Oyj a research permit for field surveys in the areas of Helsinki and Vantaa (decision MML 72172/03). The research permit applies to all alternative cable routes.

The participation and evaluation plan for the Viikinranta energy block land use plan was available on the City of Helsinki's website until 18 June 2021.

Ramboll Finland Oy has been chosen in May 2021 as the consulting company used for the general planning.

Parviainen Arkkitehdit Oy has been chosen in April 2021 for substation architectural and structural planning.

Contact details

Fingrid Oyj

Risto Ryynänen

Project Director 
tel. +358 30 395 5219

Jussi Rantanen

Project Manager (cable connection)
tel. +358 30 395 5274

Jarmo Henttinen

Project Manager (substations)
tel.+358 30 395 4280

Joonas Hurtta

Project Engineer
tel. +358 30 395 4297

Lotta Hakanpää

Communications Specialist
tel. +358 30 395 5365

e-mail addresses: firstname.lastname@fingrid.fi


General planning consulting company Ramboll Finland Oy

Martti Maljanen

Project Manager
tel.+358 50 361 7736


Architectural planning Parviainen Arkkitehdit Oy

Bratislav Toskovic

tel.+358 50 589 6913