Heating and sanitation technician – VVS, 1/2021 Text: Robert Wilkund
A unique pilot project is currently underway at the Cronehov ice rink in Kronoby, where KS-Geoenergi, in collaboration with Heliostorage, has drilled 36 boreholes in the bedrock to store winter cold in the bedrock. The idea is to create a cooled block of artificial frost deep down in the ground so that it can be used as a source of cold when the ice rink starts to cool down in September before the ice hockey season begins. The aim of the pilot project is to reduce the high energy costs incurred each year in cooling down the ice rink after the summer. It requires turning on the refrigeration system to start the cooling process in order to create the conditions to put ice in the hall. In addition, solar collectors are included in the project and these create heat to dry up the hall in May after the season ends.
When the conserve is melted in the spring, it takes a lot of energy to dry up and prevent moisture damage, and to heat and ventilate the moisture. Vice versa, a lot of cooling energy is required when the ice rink is cooled down again in the fall. The project is a joint venture with KS Geoenergi and the start-up company Heliostorage in Kokkola.
– “We have now installed a standard cooling element and a control logic where the circulation pumps for the cooling medium start when it is below zero outside and pump the winter’s cold into the storage. By the end of February, we expect 100 m² of Heliostorage’s solar collectors to be installed on the roof,” says Timo Sivula, Development Director at Heliostorage.
Heliostorage’s solar collector modules can capture both cold in winter and heat when the sun shines. The project also includes two different thermal storage facilities that will be built. A cold store will be built where the modules are expected to create a massive cube of artificial frost during the winter, and a hot store will be built in another location, which will be charged with excess heat from the solar collectors during the summer. The cold store is used to cool the hall in the fall and the warm store is used to heat the changing rooms and stands in the winter. At the time of going to press, the Kronoby ice rink has stored 5 MWh of cooling energy in the ground. The return line has a liquid temperature of zero degrees.
