All new Sainsbury’s supermarkets have used CO2 transcritical systems since 2010. Accelerate Europe reports.
As a committed adopter of natural refrigerants, UK retail giant Sainsbury’s has a nationwide policy of installing CO2 transcritical systems in all new supermarkets, as well as in major retrofits.
“Natural refrigerants are part of our DNA,” says Paul Arrowsmith, refrigeration design manager in the property department of Sainsbury’s Supermarkets Ltd.
Early CO2 trials began in 2008 and all new supermarkets have been delivered with CO2 since 2010.
“If we deliver a new supermarket, it will be CO2,” Arrowsmith says. “This year we also made a step-change in convenience stores – every new convenience store will be rolled out using a natural refrigerant – primarily CO2.”
“The first stop is that we always use a natural refrigerant,” he explains. “The commitment is to natural refrigerants wherever possible.”
Sainsbury’s is putting the HFC phase-down at the heart of its strategy for reducing operational carbon emissions by 30% absolute and by 65% relative (versus 2005) by 2020. The 2020 goal is part of a broader target of an absolute carbon reduction of 50% by 2050.
The supermarket giant operates 1,415 stores across the United Kingdom (May 2017 figure). It currently boasts 216 CO2 transcritical supermarkets among its portfolio. It also has eight convenience stores with natural refrigerants – seven with CO2 booster systems, and one with a hydrocarbons-glycol configuration.
Older stores installed between 10 and 20 years ago continue to operate on HFCs, so the company cannot yet say that it is HFC-free.
“When systems come to the end of their useful life, we’ll replace them with a CO2 system,” Arrowsmith says. “If we’re doing a substantial amount of work and changing nearly all the fixtures, then we’d change it out to CO2.”
“The commitment is to natural refrigerants wherever possible.”
– Paul Arrowsmith, Sainsbury’s
Cost-neutral with HFC systems
One oft-cited barrier to wider market penetration of natural refrigerant-based HVAC&R systems is a reported shortage of components, particularly for more complex CO2 systems. Major end users like Sainsbury’s therefore have the power to change the market by placing large orders. Procurement on this scale also helps to reduce the cost of natural refrigerant-based solutions by virtue of economies of scale.
“Initially we saw a cost premium for CO2, but after working with our suppliers and as the technology has become more mainstream, the cost difference has eroded away,” Arrowsmith argues.
“We’re cost-neutral with HFC installations.”
Some customers cite the perceived complexity of natural refrigerant-based HVAC&R systems vis-à-vis their HFC counterparts as another obstacle to overcome. But Arrowsmith argues that the situation is changing fast.
“Componentry now, for Sainsbury’s and for our supplier base, is business-as-usual,” he says. “There is no problem finding suppliers. Yes, there are new components and emerging technologies like ejectors and parallel compressors, which we evaluate. But availability of system components is not an issue.”
CO2 refrigerated trucks
Sainsbury’s is also trialling natural refrigerant trailer units for its delivery trucks. In April 2016, it became the first customer in the world to receive Carrier Transicold’s prototype transport refrigeration system based on CO2 refrigerant.
The April delivery was the first of three units to join Sainsbury’s fleet in 2016 as part of a three-year technology field trial.
The current trial builds on the success of a 2013 pilot, which saw the supermarket operate a modified road-ready version of Carrier Transicold’s NaturalLINE refrigeration system for ocean containers.
The 2013 pilot was the first natural refrigerant-based truck operating anywhere in the world.
Click here to read the full version of this story in the autumn edition of Accelerate Europe.