Anna Pasma, Chief Executive Officer of Oulun Energian Sähköverkko Oy, notes that the importance of environmental issues is emphasized especially when the network is being extended to entirely new areas.

"We are always involved in planning even as early as in the zoning phase of an area. At that point, we draw broad lines where the electrical cables, distribution substations, and power plants can be placed," she states.

The zoning phase is followed by electrical engineering project planning, followed by terrain planning. The latter includes surveys of the terrain—including in the urban area—after which the exact locations of the different parts of the network can be determined.

In addition to site planning, terrain planning also covers applying for the necessary placement and construction permits, contracts with landowners, and site markings. According to Anna Pasma, different natural and scenic assets, groundwater areas, flood risks, ancient relic protection areas, and the location of acid sulphate soil are taken into consideration when constructing the network.

"We respect such factors. The network cannot always be constructed in such a simple manner that would be most desirable from the point of view of the network company," she explains.

Collaboration is important

Pasma emphasizes the importance of seamless collaboration—in which landowners and planners, in addition to the network company, take part—in the planning and construction of the network.

"There is always a good solution for everyone," she promises.

Environmental factors also affect the maintenance of the existing electricity network. This is best seen in the parts of the network that have overhead cables. According to CEO Anna Pasma, when renovating overhead cables, the aim is to utilize the same streets the cables were located on previously or to place the cables along the roads.

"This minimizes the scenic nuisance of the overhead cables," she states.

The total length of the cables in the Oulun Energia electricity network is 4,157 kilometers, of which about 13% are overhead cables.

Environmentally safe distribution substations

There are 1,222 distribution substations in the company's network. Oulun Energian Sähköverkko improves the safety of the distribution substations by equipping the substations with wet sumps. Column transformers in groundwater areas have also switched to using biodegradable oil-cooled transformers.

These measures will prevent environmental pollution in the event of an oil spill. In addition, groundwater areas are marked in the computer systems. This means that in the event of a fault, it is immediately known whether, for example, the transformer is in a groundwater area and it makes it possible to take effective measures to protect the environment and the groundwater.

It is also environmentally responsible that all of the components of the electricity network are as low-loss as possible. This makes the electricity network energy efficient.

The article was originally published in the Oulun Energia customer magazine in March 2021. Text by Kari Arokylä.