F-gases used in novel data centre free cooling systems
Data centres and telecoms are responsible for a significant environmental footprint but are becoming more energy-efficient, reusing waste energy, and using more renewable energy sources. This is driving innovation for cooling systems including increased use of free cooling. HFCs, HFOs and HCFOs are playing an important role, particularly for large systems. Three recent innovations by European companies are summarised.
A new cooling range specifically designed for data centres is capable of optimised performance, including energy saving. Special cylindrical condensers increase the heat exchange surface by 45%, but in this innovative configuration, they can be extended, effectively doubling the heat exchange surface while maintaining the same physical footprint. The range is designed to use R-134a, R-513A and HFO-1234ze and is equipped with 8 oil-free centrifugal compressors and 4 refrigerant circuits for a cooling capacity that reaches 4200/4400 kW. All the condensing sections operate in parallel on several refrigeration circuits maximising the surface area of the condensers at partial significantly increasing performance in terms of energy efficiency, achieving efficiency ratings of EER 4.59 (W/W) at 40°C ambient and EER 5.34 (W/W) at 35°C ambient temperature.
Source Refrigeration Industry and manufacture’s information
A European company is supplying its innovative energy efficient, thermosiphon-based dry cooling solutions for data centres in the USA. The solution has been developed to minimize the environmental impact of data centres by providing free cooling without the use of water. A waterless cooling system providing an efficient cooling solution for new and retrofit installations is particularly important where access to a suitable water supply may be limited, expensive or unreliable. The thermosiphon technology captures maximizes free cooling and with low fan energy, results reduced annual cooling energy compared to other waterless technology. In 2021 the thermosyphon system received a prestigious award, Mission Critical's 2021 Top Tier Product Award for Thermal Management Solutions. According to product literature the thermosiphon-system uses R-134a.
Note: The thermosyphon system is a closed loop that circulates refrigerant by gravity. Thermosyphon heat exchangers move heat from the data centre to ambient through the evaporation of liquid refrigerant in the evaporator and condensing in the condenser. Transition to using an active cooling system occurs as ambient increases.
Source Refrigeration industry and manufacture’s information
A new range of chillers with inverter screw compressors for large data centres is designed to provide greater efficiency, precision, and configurability to help maintain data centre sustainability and better adapt to current and future cooling challenges. The air-cooled extra-large chillers (300 -2200kW) have an integrated free-cooling system and provide increased cooling capacity and lower power consumption for higher energy efficiency in a wide range of environmental conditions. The chillers are flexible for refrigerant choice and are suitable for R-513A, HFO-1234ze and HFO-1224yf as well as R-134a.
Source Digital Infra and manufacture’s information