Breaking new ground for transcritical CO2 systems
BITZER Australia approached SWEP to create a new transcritical CO2 system for a Woolworths grocery store in Sydney, Australia. SWEP has led the global development of ultrapressure brazed plate heat exchangers for transcritical supermarket refrigeration for the last decade and was prepared to solve the challenges that the hot Australian climate poses for transcritical systems.
Designing a new transcritical solution
BITZER was asked to design a transcritical CO2 system at a Woolworths store in Sydney, Australia.
BITZER has been making a contribution with innovative products and services for 80 years. Their products maintain the optimal temperatures on buses, trains and in buildings to ensure food stays fresh on its way to customers around the world.
SWEP was able to provide a technical solution for this project, which allowed BITZER to design a system to meet the requirements of the customer. The design of the chilled water thermosyphon unit with low refrigerant side pressure drop was essential to the operational principle of the system.
SWEP B12, B200T and B18 were used in this project. Chilled water production (+8/+12) via CO2 thermosyphon. Suction superheat control for Low Temp compressors via liquid. Condensate subcooling via flash gas. Vapour condensing via R134a mechanical resilience unit. Heat reclaim to water via discharge gas for store heating.
A powerful system and an award-winning solution
SWEP B12, B200T and B18 brazed plate heat exchangers were used in this project. The project also features: Chilled Water production (+8/+12) via CO2 thermosyphon for store air conditioning. Suction superheat control for low temperature compressors via liquid. Condensate subcooling via flash gas. Vapour condensing via R134a mechanical resilience unit. Heat reclaim to water via discharge gas for store heating.
The SWEP and BITZER designed system was commissioned in December 2018 and handled the January 2019 heatwave in Sydney with flying colours.
In early February 2019, an ambient peak temperature of 48 °C ambient was recorded on the gas-cooler deck, yet the system – which serves 34 kW of frozen produce load, 205 kW of chilled produce load, 325kW of space cooling and 12 kW of heating – delivered compliant temperature performance to all connected loads.
When asked why BITZER chose to team up with SWEP on this project, Ian Suffield, National Engineering Manager, BITZER Australia, said “We work with SWEP on a lot of different projects every year. The product knowledge and support available from SWEP by Australian based engineers means we get great service and technical advice within a short time. The SWEP product has also shown the versatility of their range with the number of different solutions we needed for this project.”
In 2019, Woolworths won the Refrigeration Excellence category at the AIRAH awards and continues to break new ground for transcritical CO2 systems in Australia’s hottest climates.