Enersense builds high-voltage transmission line using low-carbon concrete

Enersense is constructing a 400 kV high-voltage transmission line in northern Finland for the transmission system operator Fingrid, using low-carbon concrete elements in the foundations. To the best of current knowledge, this is the first time low-carbon concrete structures have been used in the construction of a high-voltage electricity network in Finland. The pilot is being carried out in collaboration with the precast concrete manufacturer Consolis Parma.

Concrete plays a key role in grid construction and is used in almost all foundations of high-voltage transmission towers. In total, the project covers approximately 117 kilometres of transmission line, around one third of which will be built using low-carbon concrete elements.

The project will utilise nearly one thousand low-carbon concrete elements, requiring more than two million kilogrammes of low-carbon concrete in their manufacture. The construction process remains unchanged: the elements are cast at the factory and installed underground on site, after which the towers are erected on top of the foundations. The elements are produced at Parma’s Oulu factory.

“Cement production is a significant source of emissions, and we are continuously seeking new ways to reduce emissions from construction in order to support our customers in achieving their sustainability targets. The use of lower-carbon concrete is one example of how we can strengthen our customers’ positive environmental impact while also setting an example for the industry and society through more environmentally friendly construction. Pilots of this kind are important for Finland’s carbon neutrality goals,” says Santeri Hirvonen, Director of Transmission Line Construction Finland at Enersense.

Low-carbon concrete elements reduce emissions by 15 per cent

The foundation elements are manufactured as PARMA Green products in accordance with the low-carbon classification of the Finnish Concrete Association, using a concrete mix with emissions 15 per cent lower than the standard level. The use of low-carbon concrete mixes requires third-party certification from the manufacturer.

“Our environmental development work focuses on the manufacture of low-carbon products, energy efficiency and the circular economy. Our climate target is to reduce our emissions by five per cent annually and to halve them by 2035,” says Juha Rämö, Chief Technology Officer at Consolis Parma.

“Last year, more than half of our production consisted of low-carbon PARMA Green products. In this transmission line project, carbon dioxide emissions will be reduced by nearly 50,000 kilogrammes thanks to the low-carbon alternative,” Rämö adds.

The end customer for the project is Finland’s transmission system operator, Fingrid.