Excess heat from Kilpilahti plants could cover 25% of Helsinki's district heating
In Finland, the production plants of Neste and Borealis Polymers located in Kilpilahti, Porvoo, produce a significant amount of low-temperature excess heat, but no solution exists to utilize this energy. On the basis of a recently completed preliminary study by Neste, Borealis and energy companies in the Helsinki Metropolitan area, the use of excess heat in the production of district heating is technically feasible.
The study, which was funded by Neste Corporation, Borealis Polymers Oy, Fortum Power and Heat Oy, Helen Oy, Vantaan Energia Oy, Porvoon Energia Oy – Borgå Energi Ab and Keravan Energia Oy and conducted by Neste Engineering Solutions Oy in cooperation with Gaia Consulting Oy, finds that excess heat from the Kilpilahti plants could cover approximately one-quarter of the district heating volume required in the Helsinki region.
Even more excess heat would be available, but its use is limited by the decreased need for heat in the summer season. In addition to the Helsinki region, some of the studied options allow excess heat also to be used, for example, in Porvoo and Sipoo.
Three options were examined in the preliminary study.
- In the first option, district heating would be produced from excess heat in Kilpilahti using heat pumps and then transferred to the Helsinki region via a district heating pipeline.
- In the second option, low-temperature excess heat would be transferred from Kilpilahti to the Helsinki region via a subterranean tunnel and district heating would then be produced in the Helsinki region using heat pumps.
- In the third option, district heating would be produced from excess heat in Kilpilahti using heat pumps and then transferred to the Helsinki region via a district heating pipeline located inside a subterranean tunnel. The third option would enable the use of the tunnel for other purposes as well.
The preliminary study showed that the investments required, the price of the electricity consumed by the heat pumps and the level of electricity tax will all have a significant impact on the costs of heat production and the profitability of the project. Currently, heat pumps that use excess heat and are connected to the district heating system are in the highest electricity tax category, which significantly increases the price of district heating generated using excess heat.
If implemented, the project would require a significant amount of construction work and, according to the preliminary study, the delivery of heat could be started no earlier than in 2025. Next, the parties will assess their ability to continue the project to the next phase. Decisions on the next steps will be taken by the end of this year.