The municipality of Puolanka has prepared for vitality investments by modernizing the heating plant | Kpa Unicon

In the early autumn of 2020, KPA Unicon carried out a major modernization project for Honkainfra Oy, the heating company of the municipality of Puolanka.

With the upgrading, the old boiler plant received an additional lifespan of at least 10 years, and the nominal load increased by the necessary 0.5 MW.

KPA Unicon carried out the modernization project as a complete delivery, excluding electrical and automation installations. Upgrades to the electrical and automation system were implemented by Honkainfra itself.

The delivery included the dismantling of the old equipment and the roof of the plant building, the replacement of the convection part of the boiler, the installation of new equipment and the commissioning. The new convection part was manufactured at KPA Unicon’s own workshop in Kiuruvesi and the ducts and service platforms at KPA Unicon’s Lapua workshop.

“The maintenance costs of the municipal heating plant had started to rise because it was 20 years old. We observed and followed the development of the situation. It was clear that it was necessary to start upgrading the plant,” says Markku Nivakoski, Chairman of the Board of Honkainfra Oy.

Modernization is a profitable option

In the case of Puolanka, the modernization of the existing plant made sense, as the plant had been renovated over the years, and some of the equipment was still in good condition. For example, a flue gas scrubber and associated ductwork have been retrofitted.

Due to the scrubber, the plant will meet the stricter emission limits in 2030, so there was no need to make changes to the emissions. However, the technical reliability of the plant required improvement.

“The Puolanka plant is an older plant from another Finnish plant supplier but is technically familiar to us. The plant had some components in refurbished condition, which we upgraded as part of the delivery. In addition, our delivery also included a soot blower to handle the sweeping that had previously been done manually. Thanks to the new soot blower, unnecessary shutdowns of the plant during the heating season will also be avoided,” says Esa Kukkonen from KPA Unicon.

The building itself was original – cramped and low – and required an upgrade, as the new convection part is slightly larger than the old one. At the same time, an increase of one meter in height resulted in more spacious maintenance spaces and service platforms.

“The old roof had to be dismantled anyway to get the old equipment lifted out and the new equipment in. At the same time, it made sense to raise the ceiling so that we could get more functional facilities,” Nivakoski explains.

Owing to the modernization, the plant’s capacity increased from 2.5 megawatts to three megawatts. Besides the renovation, the boiler was also equipped with circulation gas ducts, which enables the use of a drier fuel if necessary.

The dimensioning of the nominal load increase took into account the municipality’s goal of increasing business, employment and production related to wood raw material.

“Since there was not detailed information at the time about, let’s say, the future load needs for the next decade, this was a good time to do the renovation. Its repayment period is estimated to be 10 years. In that time, we’ll be able to see the results.”

Nivakoski knows that when upgrading an old plant, compromises will have to be made. For example, part of the old duct system was left in use even though it is almost at the end of its lifecycle.

“We can correct the small deficiencies in them in the coming summers. Overall, the usability and conditions of the plant have improved significantly,” he asserts.

Alongside the increase in capacity, the use of reserve boilers has decreased. Likewise, maintenance and operating costs have also been reduced since the sweeping costs are lower. Operating services Honkainfra procures from the Municipality of Puolanka.

“In practice, the boiler plant employs 0.5 man-years: one person is responsible for operation and maintenance, and the municipality’s property maintenance is responsible for operation after normal working hours.”

The parties are satisfied with the outcome

The project started in May 2020 with competitive bidding. The procurement contract was signed at the end of June/beginning of July, and the actual demolition work at the plant began at the end of August. In August, the old boiler was also shut down for demolition work, with a total downtime of 3-3.5 months. The heat demand during that time was met with a reserve boiler plant that used oil as fuel.

“Last autumn there was good weather, and the heat consumption was very moderate, which was also reflected in the oil consumption. The price of oil was also really low last year,” states Kukkonen.

The first fires in the refurbished boiler were lit after mid-November. At the same time, the necessary practical tests were carried out and the plant started up. The handover of the project to the client took place just before Christmas, on December 18, right on schedule. According to Kukkonen, both parties are satisfied with the outcome.

“This project was done with very good cooperation. From our point of view, the timing of the project was also very good. It would be ideal to continue the summer maintenance and modernization project season a little further into the fall so that everything would not be scheduled for July. This would make it easier to resource projects, as KPA Unicon has over a hundred people working on maintenance and modernization projects during the summer.”

In total, in 2020, KPA Unicon carried out dozens of modernization and several new plant delivery projects. It would be possible to complete more Puolanka-sized projects per year.

“In the coming years, Finland will move from energy peat to domestic biomass use, which will bring new challenges and possibly a shortage of production capacity for several heating companies,” says Kukkonen.

He believes that boiler plant modernization projects will be increasingly implemented in the coming years.

“We can help energy and heat companies with those challenges.”

For more information, please contact:

KPA Unicon Oy, Esa Kukkonen,, tel:+358500949678

Honkainfra Oy, Markku Nivakoski, markku.nivakoski@, tel:+358400333993