The majority of the racks are transcritical, while a small percentage are HFC/CO2 cascade systems. The global manufacturer has seen the technology evolve since it first delivered a CO2 transcritical system in 2004.
“The technology is there to go to all climates with a high efficiency solution [that] can be rolled out worldwide,” said Sascha Hellmann, project leader of systems development at Carrier Commercial Refrigeration Europe, during the innovation session.
“The technology is there to go to all climates with a high efficiency solution [that] can be rolled out worldwide.”Sascha Hellmann, Carrier Commercial Refrigeration Europe
Hellmann explained how Carrier had come up with several innovative solutions for CO2 transcritical, depending on end users’ needs and preferences. “There is no ‘one size fits all’ approach,” he said. “We have a tailored solution to improve efficiency all year round.”
Carrier’s CO2 transcritical solution with a modulating ejector and an economiser cycle (with an additional compressor on the rack to compress flash gas at a higher pressure) can improve efficiency by 20% compared to the company’s first generation transcritical system.
They also have the option to fit a CO2 pump – which reduces energy consumption via a full-year medium temperature flooded operation – a mechanical sub-cooler, high-efficiency compressor motors and an adiabatic gas cooler for rack systems that can be combined or used together in different systems.
Heat recovery, air conditioning and heat pumps can be added as well.
The ability to tailor the rack with different add-ons means it can be used in bigger applications. This quarter, Carrier finished a large capacity, semi-industrial installation with a cooling capacity of 1 MW in Bremen, Germany at a Transgourmet distribution centre.
It used a modulating ejector, CO2 pump and heat reclaim, among other innovations, and replaced a previous ammonia-R404A cascade system.
This development in technology has led to increased efficiency. The company’s rack system – the CO2OLtec®Evo – can achieve a 52% Annual Energy Consumption (AEC) vs. an average 2009 store and 38% AEC vs. an average 2012-2013 store.