In Finland, municipal energy utility Helen Oy has disclosed details surrounding the revamp of its Salmisaari energy plant in Helsinki, the construction of which is to begin in late 2023. Amongst other things, wood pellets will replace coal at the Salmisaari A heating plant, where coal-based production was discontinued in spring 2023, while coal-based production of heat and power at the Salmisaari B power plant will be discontinued, and the plant will be decommissioned on April 1, 2025.
In December 2021, Helen decided to fast-track the original coal phase-out schedule of its Salmisaari energy plant and has released more details of the revamp plans.
除了将Salmisaari A to operate on pellets, new plant facilities will be built at the production site alongside Salmisaari A and Salmisaari B.
Consisting of two 50 MW electric boilers and an industrial-scale air-to-water heat pump plant, these will be deployed in heat production in the 2024–2025 heating season.
These investments in a “diverse production structure increase Helen’s energy self-sufficiency” as it continues the green transition towards carbon-neutral district heat and cooling for the Finnish capital city.
First-of-its-scale air-to-water heat pump
The air-to-water heat pumps, in turn, will produce approximately 61 GWh of district heating and 10 GWh of district cooling per year. Their district heating power will be 14 MW and their district cooling power 8 MW.
The air-to-water heat pumps will be the first of their scale to be built in Finland. Air-to-water heat pumps use outdoor air as their energy source and can produce district heat from outdoor air as cold as -8°C.
During the summer season, the heat pumps are also used to produce district cooling. The heat produced by air-to-water heat pumps and electric boilers replaces heat production based on fossil fuels.
The new electric boilers will reduce Helen’s carbon dioxide (CO2) emissions by more than 240 000 tonnes over their first five years of operation, and their combined power can be as high as the peak consumption of the Lauttasaari district. Our goal is an 80 percent reduction in emissions by 2025 compared to the emissions in 1990, and we are also aiming for carbon-neutral energy production by 2030, said Timo Aaltonen, SVP, Energy Platform and Production Solutions at Helen.
Construction start in late 2023
The new units will be built at the Salmisaari site, near the front of the current plant, on the Porkkalankatu side.
The red-brick facade of the plants will respect the historical architecture of the production site, enclosing the exterior of the current technical building at the site and thereby creating a more coherent cityscape.
The actual construction work will begin in late 2023 and will lead to new arrangements for pedestrian and bicycle traffic.
Increase the use of bioenergy
In line with Helen’s plans, production from bioenergy will be increased by converting the coal-powered boiler plant at the Salmisaari production site into a wood pellet-powered plant.
The pellet boiler will replace coal at the Salmisaari A heating plant. The boiler will see its heaviest use during winter when the demand for heat is at its highest. The plan is for the pellet boiler to start producing heat for the district heating network in the 2024–2025 heating season.
The Salmisaari site is also supplemented by the existing heat storage infrastructure that will undergo alterations this year.
