R744 comes out on top in Comparative Study of Refrigeration Systems for Ice Rinks

CO₂ technologies emerge as the ‘most effective’ option in a study of the choices available when renovating or replacing an ice rink refrigeration system. The CanmetENERGY study, which aims to inform the owners and managers of the 475 ice rinks in Québec about refrigeration options, compares first costs and operating costs of an R22 refrigeration system with to 11 others currently offered on the market.

With 71% of the Québec’s ice rinks over 30 years old, and 62% reliant on ozone depleting substance (ODS) R22, the CanmetENERGY study intends to respond to questions and concerns regarding the deterioration and obsolete technology used in the majority of refrigeration systems currently operated in Québec ice rinks.

Main findings of CanmetENERGY refrigeration rate CO₂ as ‘most effective’

Out of the twelve options identified, and under the criteria assessed, the two split-packed CO₂ systems, one with direct evaporation in the rink slab and one with CO₂ space heating, emerge as being the most effective, and the least expensive, refrigeration systems for ice rinks. However, the study notes that CO₂ systems are still a novelty in Québec and therefore relatively unknown. Moreover, they argue that since these systems have been in operation for less than 10 years it is difficult to evaluate the life expectancy of the CO₂ equipment.

Ice rink refrigeration systems with CO₂ offer best-combined COP 3.9

The study concludes that in addition to having the smallest greenhouse gas (GHG) emissions, systems with CO₂ offer the best combined COP (3.9), followed by the ammonia systems (3.0 on average), systems with HFC (2.6 on average) and finally the system with R22 (1.6).

CO₂ systems are also calculated to have the lowest total energy consumption, with 393 MWh/year on average versus 525 MWh/year (+34%) on average for ammonia systems and 611 MWh/year (+55%) for HFC systems. The system with R22 consumes the most with 1,020 MWh/year (+160%).

However, the study also notes that CO₂ systems carry risks and recommends a formal risk analysis when CO₂ is selected.

Study assessments

The CanmetENERGY study encompassed the following:

Refrigeration system comparison: of twelve typical refrigeration systems currently offered on the market.
Performance evaluation: of each system assuming it meets the performance requirements of a selected reference ice rink the reference ice rink is the Camillien-Houde Arena located in Montreal. This methodology permitted a precise comparison of energy costs and consumptions for a 9-month ice rink operation period.
Financial analyses: were performed over a period of twenty years and considering the following cost elements: system acquisition, taking into account the grants and incentives currently available; and work costs related to the dismantling, upgrading of the mechanical room, if required, as well as, in certain cases, the safety equipment required by the laws and regulations in this regard.
Energy costs: taking into account power demand, consumptions and current electricity rates.
Preventive and regular maintenance costs: including periodic supervision by stationary enginemen, when required.
Costs for equipment replacement: repairs or upgrades occurring over the 20-year period.
Training: specific initial and continuous refrigeration training for ice rink staff (i.e., manager, maintenance worker and refrigeration technician or stationary engineman).

Background

During the past four or five years local equipment manufacturers have installed a few dozen CO₂-based systems in Québec, in supermarkets, ice rinks and refrigerated warehouses. At this time, Québec remains the North American leader in transcritical CO₂ refrigeration systems.