The brochure – published by the United Nations Environment Programme (UNEP) and the Climate & Clean Air Coalition (CCAC) – demonstrates how propane, CO2 and ammonia HVAC&R technologies are offering efficient, climate-friendly and market-ready alternatives to HFCs.
Its publication comes as Parties to the Montreal Protocol gather in Vienna (15-23 July) for talks that could deliver a clear pathway towards a global phase-down of HFCs.
Natref systems delivering supermarket efficiency gains
The report shows how leading South African food retailer Pick’n’Pay, for example, is harnessing natural refrigerants to substantially reduce the environmental footprint of its stores. It transitioned from R22 (GWP = 1,780) to ammonia-CO2 cascade systems (GWPs = 0 and 1 respectively) in two stores – in Strand (Western Cape, near Cape Town) and Rand Park Ridge (Gauteng, near Johannesburg).
The natural refrigerants are also delivering efficiency savings of 21% at Rand Park Ridge and 13% at Strand, compared to the previous R22 systems. “The monitoring results for two years showed clearly that energy efficiency is higher for the natural refrigerant systems,” the report states.
Moreover, thanks to ongoing improvements to natural refrigerant components and control systems, “the specific energy consumption of an average store decreases constantly,” researchers found.
In the United States, the Defense Commissary Agency opted to switch from HFC blend R404a (GWP = 3,922) to a CO2-ammonia cascade system at Lackland Air Force Base, San Antonio, Texas. To increase energy efficiency, the store features LED lighting in all refrigerated cases and cold storage rooms.
Adopting the cascade system is expected to reduce Lackland’s refrigerant costs by 90% and its maintenance costs by 40%. Operational savings from energy use, refrigerant use and maintenance costs are expected to offset initial capital costs.
“Once the technology reaches large-scale commercialisation, it is expected that the lifecycle cost of future systems will be equal to or less than a typical R404a rack system,” the report concludes.
In Indonesia, the PT MIDI UTAMA group has been replacing R22 with CO2 transcritical systems in numerous Alfamidi convenience stores in Jakarta – delivering energy savings of 20% despite the high outdoor temperature climate.
The report also highlights how retailers Carrefour and Sobeys are putting the adopting of CO2 transcritical systems at the heart of their sustainability strategies, as well as showcasing the adoption of R290 solutions by German retailer Lidl and Texas retailer H-E-B.
Greening the transport sector
Norwegian retailer ASKO teamed up with Thermo King to introduce a refrigerated truck that operates without using HFCs and also requires no diesel engine, reducing emissions still further. Instead, the truck is electric and uses liquid CO2 as the refrigerant.
The report also showcases the Carrier Transicold ‘NaturaLINE’ CO2-based container refrigeration units, which help to reduce the global warming impact of transport refrigeration while offering comparable efficiency and capacity to HFC units.