Italy-based multinational CAREL is showing how new ‘EmJ’ ejector technology jointly developed with Carrier can bring high-efficiency CO2 refrigeration systems to higher ambient temperature regions than often considered feasible – potentially opening the door to wider uptake of natural refrigerant solutions in warmer climates.
“We feel that the concept of the ‘CO2 equator’ has been superseded. All limits – even trekking on Everest or in the Sahara – can be overcome if you have the right ‘gear’ or equipment,” Alessandro Greggio, Group Head of Marketing – Retail & Refrigeration at CAREL Industries S.p.A, told Accelerate Europe.
Overcoming the so-called ‘CO2 equator’ – the previously accepted geographical limit for cost-effective and efficient performance of CO2 systems in all food retail store formats – would dramatically extend the scope to use CO2 as a natural refrigerant across the spectrum, from smaller convenience stores to large hypermarkets.
“We feel that the gear that’s now available to those who wish to overcome the current limits, however challenging these may be, is adequate – as long as you have the desire and the right training,” Greggio said.
Boosting system efficiency
HVAC&R firms CAREL and Carrier Commercial Refrigeration Europe have jointly developed a new electronic modulating ejector (EmJ), which is designed to increase the energy efficiency of transcritical CO2 systems in warmer climates.
“This represents a significant leap forward in the technology available to the industry for more efficient implementation of future CO2 systems,” said CAREL’s Greggio.
The ejector helps bring CO2 systems to warmer climates without critical loss of energy efficiency, and extends their use to systems of different sizes or to systems with major variations in capacity.
“This is made possible by the truly continuous electronic modulation on the EmJ ejector, meaning that it is capable of increasing system efficiency by up to 25% – with annual averages of 10% in the typical climates of southern Europe,” Greggio said.
It also helps system designers to reduce costs by simplifying the refrigeration circuit. “The EmJ electronic modulating ejector brings positive benefits not only in terms of energy consumption, thus removing the CO2 equator, but also regarding total cost of ownership – modulating operation means that other system components aren’t needed,” he argued.
Other innovations are helping to improve the performance of CO2 refrigeration systems too. “Evaporative cooling may be a viable option for sudden peaks in annual temperature. Parallel compression and sub-coolers are already industrially available,” Greggio said.
'The CO2 equator has been overcome'
“As a result of the numerous [offerings] now available industrially and commercially, recent technological innovations, and the availability of expertise and know-how, we feel it is realistic to now consider the ‘CO2 equator’ has been overcome both in Europe and by extension in similar climates in the rest of the world,” he argued.
The company has been operating for longer in the HVAC market than in refrigeration, with market strategies for each sector designed to complement one another. There too, the potential is strong. “We have seen growing interest in natural refrigerants in several different HVAC applications,” Greggio said.
He cites process chillers, light commercial chillers and residential heat pumps as the most promising growth areas. “In these cases, the EU Eco-Design Regulation plays a similarly important role to F-Gas – indeed, perhaps an even more important one,” he said.
To read the full version of this interview in the summer edition of Accelerate Europe magazine, please click here.