A Finnish district heating company Elenia Lämpö Oy invested in Savosolar solar thermal system to produce CO2-free energy for their customer, which in this case is a nursing home located in Hämeenlinna. The heat is used for domestic hot water and pool heating.
The installation is the biggest operational solar thermal system in Finland.
Swimming halls are very well suited for solar thermal production. Typically, their heat consumption is big and the required temperature level tends to be relatively low. In such cases solar thermal collectors are operating with a very high efficiency.
However, quite often swimming halls are closed some time of the year and summertime closure may mean extra challenges for solar heat supply.
For Hämeenlinna swimming hall Savosolar solved this issue by feeding surplus solar energy in summer to the nearby district heating network. Thus, the solar system is producing heat all days and depending on the swimming hall’s actual heat demand, the facility is either a district heating provider or a consumer.
Lolland forsyning’s district heating plant in Søllested is located on the island of Lolland and was the first installation, where Savosolar’s double glazed collectors were used. The double glazing reduces heat losses through the glass side of collector and offers a higher efficiency, especially at higher operation temperature levels and during the darker months of the year. Søllested district heating plant has ca. 500 customers and also uses a 5 MW straw boiler and an oil burner to produce its heat.
The collector field in Søllested has a so-called hybrid field, with both single and double glazed collectors. The single glazed collectors are in the cold end of the collector rows and increase the low temperature as rapidly as possible, while the double glazed collectors are located in the warm side of the collector rows where it is more important to reduce the heat losses.
In Søllested, Savosolar was faced with a special challenge since the customer’s land has a sewerage pipe running through it. Since the owner of the sewer pipe needs to be able to access it in case of maintenance, Savosolar supplied a collector field which both optimised the use of the available land, while still providing access to the sewer pipe
This solar thermal plant, the largest in Europe for industrial process, will deliver on average 4,000 MWh/year of heat. It will cover nearly 32% of the heated water need for the steam generation in the local paper mill. With the very high solar yield – more than 1,000 kWh/m2 – this solar thermal field is the first of its kind in the world due to Savosolar high efficiency solar collectors installed on a single-axis tracking system, manufactured and installed for Savosolar by Arcelormittal, Project Exosun. 66 tilting structures, each carrying four 16 m2 collectors, follow the sun from morning to evening and maximize the heat production.
The project was developed and financed by NewHeat and Savosolar acted as the EPC contractor. Meaning, Savosolar designed the whole system, delivered the solar collectors, and realized the installation with local French companies. This installation will be a reference for the huge growing market of heat-as-a-service for industrial clients in France and world-wide.
