ShareReclaiming waste heat from ice rinks’ refrigeration systems to save energy
Several studies and recent cases studies show that heat recovery from the refrigeration system is the biggest energy-saving measure in ice rinks.
Ice rink operation is mainly focused on the following energy systems: refrigeration, heating, dehumidification, lighting and ventilation. The refrigeration system is the largest energy consumer in ice rinks (40 to 65%) and therefore represents the most significant potential for savings. In most conventional ice rinks, refrigeration accounts for 43% of energy use and heating for around 26%. [1, 2] Studies have demonstrated that optimising the heat recovery process, where the rejected heat is instead used to contribute to meeting the facility’s heating needs, is by far the biggest energy-saving measure. It has been shown that when an ice rink has a well-designed heat recovery system, it may even be self-sufficient on its own heat. [2]
In a recent guide, the International Ice Hockey Federation (IIHF) recommends recovering heat from the refrigeration system to minimise the need for an additional heat source. [1]
The authors of the guide also suggest optimising the heat recovery system by connecting the refrigeration system to a geothermal storage, which provides further possibilities both during warm and cold weather conditions. [1] In warm weather conditions, the storage may be used to improve the (sub-)cooling of the refrigeration process, increasing the energy efficiency of the system, while storing excess heat in the boreholes. This same heat can then be used during colder periods, when the demand for heat in the facility increases. [1]
Recent CO2 ice rink systems have demonstrated self-sufficiency with heat and the operational energy use can be reduced by as much as 55% compared with conventional refrigeration systems (HFC and ammonia). [2] For instance, the Pirkkala ice rink in Finland was renovated in 2020. The old R404A refrigeration system was replaced with an indirect CO2 refrigeration system, resulting in a 30% decrease in energy consumption. [1, 3] A new sorption dehumidifier utilises part of the recovered heat for reactivation, lowering energy consumption. [1] Operating on less than 1.4MWh of electricity per day, it has been reported that the Pirkkala ice rink is currently one of the most energy efficient ice rinks in the world. [3]
More recently, the new “Lee Valley Ice Centre”, which opened in June 2023 in North East London, uses an advanced heat recovery system to provide supplementary heating for the building, as well as domestic hot water for the centre’s visitor facilities and on-site café. [4] The rinks are cooled by four chillers based on high efficiency inverter-driven screw compressors, with a combined cooling capacity of 800kW. The chillers deliver cold to the twin ice pads via a secondary glycol circuit, and are compatible with R1234yf. [4]
Sources
[1] International Ice Hockey Federation (IIHF). Guide to Sustainable Ice Arena. (2023) https://blob.iihf.com/iihf-media/iihfmvc/media/downloads/projects/ice%20rink%20guide/230519_iihf_sustainable-ice-rink_guide.pdf
[2] Bolteau S., Grönqvist C., Rogstam J. 25th IIR International Congress of Refrigeration, 2019. Field measurements of CO2 refrigeration systems with heat recovery in retrofitted ice rinks. https://iifiir.org/en/fridoc/field-measurements-of-co2-refrigeration-systems-with-heat-recovery-in-35102
[3] CO2 Refrigeration Helps Cut Electricity Use at Finnish Ice Rink by 34%. https://r744.com/co2-refrigeration-helps-cut-electricity-use-at-finnish-ice-rink-by-34/