Rovakaira Oy

Rovakaira Oy distributes power in northern Finland to more than 31,000 customers. It covers an area of 28,800 square kilometres with almost 7,000 km of distribution network in some of the harshest weather conditions in the world.

Located in the Arctic Circle, the challenges of servicing a population that is widely spread amongst many small hamlets and villages of Lapland are increased by extreme weather conditions that include strong arctic winds, heavy and deep snow for half of the year, long periods without daylight, and severe temperatures that can reach as low as -51°C. In these conditions, maintaining a reliable supply of energy to customers can literally be a matter of life or death. Therefore, it’s not surprising that Rovakaira Oy is required to meet stringently regulated targets to satisfy low distribution costs and outage rates for its customers.

Traditionally, the use of creosote or CCA-type wood preservatives has given wooden utility poles a lifespan of anything between 35 and 50 years. Ongoing and future changes to wood preservative legislation across Europe, including the ban of creosote, are now leaving many utilities looking for a cost-effective and proven means of maintaining or increasing the service life of their replacement poles.

For many utilities, including Rovakaira Oy, the cost of replacing rotten poles is one of their single largest annual maintenance costs.

Rovakaira Oy considers the failure of wooden poles from ground-line decay a major problem, as it typically occurs during severe winter conditions. Annually, Rovakaira Oy was experiencing an average of 120 overhead line faults, replacing 2,000 poles each year. Improving network reliability, reducing long-term maintenance and repair costs, and preventing overhead line repairs in adverse weather conditions were the driving factors behind Rovakaira Oy investigating enhanced pole protection alternatives.

Rovakaira Oy considered a range of options to satisfy the requirements of both improved network reliability and the reduction of long-term maintenance costs, including:

Working in partnership with their approved pole supplier, Rovakaira Oy established the following product evaluation criteria:

Of the three options investigated, the Polesaver ground-line barrier sleeve was the only product that satisfied these exhaustive criteria.

Once applied, the bituminous liner inside the outer thermoplastic sleeve melted to form a tough watertight seal to the pole surface. This seal effectively lowers the entry point for moisture to the pole, keeping the zone inside the sleeve relatively dry — below the 25% level when decay may occur. Even if punctured or damaged, the area of wood exposed to water ingress that can lead to decay is limited to the damaged area only, unlike the other systems. This product also proved to be easy to apply to the pole and was the lowest-cost option of the three products evaluated.

Rovakaira Oy first began initial trials of the Polesaver solution in 2011 and has subsequently successfully installed more than 10,000 poles fitted with Polesaver sleeves across their network. Significant cost savings have resulted from longer pole life and improved safety and reliability.

The result of this program for Rovakaira has seen an overall reduction in outages, and repair and maintenance costs, and the Polesaver ground line protection solution has been adopted as the standard for all of its new and replacement overhead poles.

To learn more about how Polesaver can benefit your utility get in touch with us today