In the joint project between Seinäjoen Voima and Seinäjoen Energia, earthworks have been carried out during the past spring and early summer. The foundation work at Seinäjoen Voima’s district heating plant area on Puhdistamonkatu has been completed for the heat pump plant, through which district heating and district cooling will be produced from the wastewater of the adjacent wastewater treatment plant.
Seinäjoen Voima’s Managing Director Pasi Salo states that the project has progressed as planned. The foundation work has been completed, and the construction site will be handed over to the contractor responsible for the building work at the beginning of July.
“From July onwards, the construction work for the heat pump plant will begin. As the construction work progresses, heat pumps and other necessary equipment will be installed. The installation work will take place between July and October, and the plant will be commissioned in November-December,” explains Salo about the upcoming phases of the project.
What is the heat pump project about?
Salo explains that the project utilizes the thermal energy contained in wastewater. The temperature of the purified wastewater, i.e., technical water, varies between 11 and 20 degrees, which enables the use of purified wastewater for production purposes with heat pumps.
“On the side of the wastewater treatment plant, an equalization basin will be built, where the warm purified wastewater will initially be discharged. From the equalization basin, the wastewater will be transferred through pipelines to the heat pump plant. After this, the heat from the wastewater will be collected with a heat pump, and the heat will finally be transferred to the district heating network with the help of heat pumps. The purified wastewater becomes technical water and is returned to the wastewater treatment plant at approximately 4 degrees, from where the purified water is discharged into the river,” explains Salo about the process.
In addition to district heating, the project will also produce district cooling. The district cooling produced at the heat pump plant will be collected from the intermediate circuit of the heat pump and used for cooling buildings.
The project progresses step by step as follows:
- Construction work will take place on Puhdistamonkatu at Seinäjoen Voima’s district heating plant and the adjacent Seinäjoen Energia wastewater treatment plant areas.
- At the wastewater treatment plant, a 1,000 cubic meter equalization basin will be built for the purified water. From the equalization basin, a 300-meter-long pipeline for technical water will be built to the heat pump plant.
- Foundations will be built for the heat pump plant on the heating plant’s site, upon which the heat pump plant will be delivered. The plant’s area is approximately 250 square meters.
- For the production of district cooling, a main line of approximately 1.5 kilometers will be built, starting from Puhdistamonkatu and continuing to the Joupin area.
- Seinäjoen Energia will be responsible for the planning and management of the construction of district heating and district cooling pipelines.
- Seinäjoen Energia will purchase the heat produced in the process from Seinäjoen Voima.
The three heat pumps included in the project are the first in the history of Seinäjoen Voima. They are also the first ammonia heat pumps in the entire EPV Group.
When completed, the project will produce approximately 45 GWh of heat per year, which corresponds to 8–9 percent of Seinäjoki’s district heating needs. The nominal capacity of the heat pump plant is approximately 5 MW.
More sector coupling with emission-free production solution
Thanks to the project, the share of emission-free energy production at Seinäjoen Voima will increase further, which also supports the parent company EPV Energy’s New Electricity Revolution strategy.
According to Salo, the project will reduce Seinäjoen Voima’s CO2 emissions by approximately 15,000 tons per year. For the company, the project also means the introduction of a new production solution that increases sector coupling.
“The project is a continuation of the production solutions introduced in recent years, with which we have reduced the share of energy produced by combustion. At the same time, we are also promoting increased sector coupling in our energy production, which is thus a continuation of Seinäjoen Voima’s electric boiler investment. These solutions increase production flexibility, which allows us to guarantee energy delivery to customers regardless of conditions.”
The project has received funding from the European Union’s NextGenerationEU through the Ministry of Employment and the Economy, which covers 25 percent of the costs incurred. The total investment cost is approximately 7.7 million euros.
For more information: Pasi Salo, Managing Director of Seinäjoen Voima, tel. 010 505 5325
