Requalification work on two refrigeration plants: reduction and replacement of R-22 gas
Spike Renewables carried out two requalification projects on as many refrigeration plants with different characteristics and functions, yet both sharing the need to significantly reduce the use of R-22 refrigerant, now subject to strict environmental restrictions.
The first system was based on an ice-storage solution, designed to handle peak loads and provide cooling reserve. The second plant was dedicated to industrial refrigeration of cold rooms for food storage. In both cases, the objective was to ensure operational continuity, improve efficiency, and achieve a substantial reduction in environmental impact.
Objectives and Design Approach
In the ice-storage system, the intervention involved a complete replacement of the coil supply, switching from a direct-expansion R-22 circuit to an indirect glycol-water circuit. This transformation made it possible to eliminate the refrigerant from the storage tanks while maintaining the same thermal capacity and improving overall system reliability thanks to the concentration of the refrigeration circuit within a fully inspectable section.
Technical checks and feasibility analyses confirmed full compatibility of the coils with the new heat-transfer fluid and the preservation of the original performance. The intervention involved a large-scale infrastructure: each tank had a storage capacity of approximately 36,000 kWh, supported by more than 50 submerged coils. The new circuit required the installation of flooded evaporators rated at 3,600 kW each, and the management of glycol-water flow rates in the range of 150–160 l/s per tank—values that highlight the scale of the engineering and system upgrades.
For the refrigeration plant dedicated to cold rooms, the strategy followed a different path but with the same goal: reducing the presence of R-22 through a retrofit of the low-temperature circuit. Several replacement refrigerant blends were evaluated, with particular attention to low-environmental-impact options, and the system’s operating conditions were analyzed to define the most suitable solution. The work restored operation of a line that had been out of service, ensuring technical compatibility and regulatory compliance.
In the low-temperature circuit, the requalification involved the recovery and replacement of approximately 200 kg of R-22. This figure highlights the environmental relevance of the intervention and the importance of transitioning to alternative refrigerants with lower climate impact.
Key Results
Both projects achieved a significant reduction in R-22 use: complete elimination in the ice-storage plant—where the refrigerant was fully removed from the storage circuit—and substantial reduction in the cold-room system, where replacement with alternative gases allowed the plant to be restored and environmental impact minimized.Requalification also improved overall system reliability thanks to more modern, maintainable configurations, and extended the plants’ operational life without requiring full equipment replacement.
These two interventions demonstrate how a targeted engineering approach can make existing plants more sustainable, regardless of their intended use. By reducing or eliminating R-22, Spike Renewables contributed to modernizing complex infrastructures while enhancing performance, safety, and environmental impact of the refrigeration plants.