In August 2018, a fruit grower in the Dutch province of Zeeland opened a new cold storage facility based on a propane (R290)-CO2 system.
The facility stores 500 tonnes of hard fruits, mostly pears. The system works from August, the harvest time for pears, until May/June. Thus it stands still during the summer months.
Dutch company Cool Green Solutions provided the cooling system, which was installed by Houg Koeling Terneuzen. The propane cools the CO2, which is pumped and acts as a brine. Bitzer provided the compressors, the heat exchanger is from SWEP, and ThermoKey made the condenser.
The system has two hermetically sealed R290 circuits. Each has a charge of 14 kg. The total cooling power is 120 kW. According to Wim de Leeuw, director at Cool Green Solutions, installations with over 100 kW of cooling capacity are generally cooled by natural refrigerants in the Netherlands.
The customer chose the R290-CO2 combination due to the great efficiency of R744 as brine. CO2 is particularly effective for hard fruits, as it has low temperature fluctuations. This prevents the fruit from drying out. No oil is used in the CO2, further increasing its heat transfer capabilities.
Cool Green Solutions was founded in 2010 to make the use of natural refrigerants easier. The company works with all the natural refrigerants: CO2, hydrocarbons and ammonia.