The Helsinki 400 kilovolt power cable connection

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

In close cooperation with the City of Helsinki and Helen Sähköverkko, Fingrid is implementing a new 400 kilovolt cable connection to the main grid to Helsinki to meet the growing electricity consumption in the capital region and promote the green transition. The planning of the project started in 2020 and the connection will be completed in 2026.

By clicking the photo, you can view the route from Fingrid's map service.

Project status

The project is currently in the building phase from the Länsisalmi substation in Vantaa to the new Vanhakaupunki substation in the Viikinranta energy block in Helsinki.

Current News

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 2024

Timetables of the construction site areas (in Finnish). The timetables are preliminary and may change from those announced.

HKI400 timetables

News 2023

In December, tree removal began on the expropriationed cable route and in the construction site areas. The tree removal will continue in the spring of 2024. The marking of the area will be done by Mitta Oy and the tree removal will be carried out by Kone-ja Metsäpalvelu Saarenpää Oy.

EXACT AIP-Mittaus Oy has been selected as the cable route measurement consultant in December.

Demir Kablo, Turkey, has been selected as the supplier of the 400 kilovolt cable in December.

The town plan of Viikinranta's energy block (Vanhankaupunki substation) became legally binding on November 6.

Fingrid received an expropriation permit decision regarding the cable route's lead area from the National Land Survey of Finland on November 1. (MML Decision 20030/03 04/2023). The takeover meeting was held on 27.11.

GRK Suomi Oy was selected as the contractor for the other building blocks of the cable route in November.

Lännen Alituspalvelu Oy has been selected as the contractor for the cable route's horizontal drillings in October.

Hyosung Heavy Industries Corporation, South Korea, has been selected as the supplier of the 400 kilovolt reactor of Länsisalmi substation in October.

Tamini Trasformatori S.r.l., Italy has been selected as the supplier of the power transformer in Vanhakaupunki. 

Hitachi Energy Finland Oy has been selected as the substation contractor for Vanhakaupunki and Länsisalmi in October.

A-Insinöörit Suunnittelu Oy has been selected for the construction design of the Vanhakaupinki and Länsisalmi substations in October.

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

Jari Heikkilä

Construction Consultant
tel. +35840 725 2673