Acciona in for seawater heat recovery project

The Finnish energy group Helen has agreed to work with the Spanish construction firm Acciona and its Finnish consortium partner YIT on a €400 million project to recover heat energy from seawater.

The undersea tunnel at Salmisaari will be the third longest of its type in the world. Photo: Adobe Stock

The project will see a TBM (tunnel boring machine) operating in Finland for the first time, boring a 17km-long undersea tunnel, at depths of up to 70m.

The tunnel will deliver seawater at around 2 degrees Celsius, to heat pumps to be built in Salmisaari, Helsinki, where it will be converted into energy for both heating and cooling systems in the district of the capital.

The scope of the consortium’s work will include the construction of the underground chambers into which the pumping equipment will be installed.

It will also use drilling and blasting techniques to build a second tunnel of 9km in length, to return excess water to the sea, and will take on all associated engineering works on the project.

An appeal period will now run until the end of this month, after which it is anticipated that the project will move to a development phase, expected to last until autumn 2024.

Following this phase, implementation of the project will begin, with an estimated completion date in 2029.

Huberto Moreno, CEO Construction of Acciona, said, “We are very proud to have been selected to execute this project together with YIT. This is our first project in Finland and will be the first Tunnel Boring Machine (TBM) project in Finland. I am convinced that, together with our client, we will be able to carry it out successfully providing to the alliance team our massive Tunnel Boring Machine worldwide experience.”

Pasi Tolppanen, EVP, Infrastructure segment at YIT, said, “It is great to be able to develop and implement a project that is unique in Finland and is right at the heart of our strategy. It will allow us to use our diverse expertise, including excellence in rock construction and at the same time contribute to both YIT’s and Helen’s ESG goals.”