While many food retailers around the world have installed transcritical CO2 refrigeration in new stores, fewer have undertaken a major effort to retrofit existing stores with the technology, preferring to get more use out of legacy systems.
But giant Polish discount retailer Biedronka, part of the Portugal-based Jerónimo Martins Group – and winner of the Accelerate Magazine/Europe 2019 Best in Sector/Food Retail award – has taken a different approach. Out of its more than 2,900 stores, around 600 were retrofitted with transcritical CO2 between 2017 and October of last year, with another 300 existing stores slated to be equipped with the technology this year. The company is also converting its 16 distribution centers to CO2.
Biedronka, a 25-year-old chain based in Kostrzyn, Poland, has also installed transcritical systems in new stores, including 350 as of last October, and another 150 planned for 2020. In December 2019 alone, the company opened 80 new stores with CO2 equipment, according to Wojciech Polak, Technical Director for Biedronka, who recently spoke to Accelerate Magazine.
CO2 is not Biedronka’s only natural refrigerant. About 20% of its display cases use propane (R290) plug-in units. In a natural refrigerant store, a common configuration includes 10-12 medium-temperature cabinets using CO2 (along with medium-temperature and low-temperature cold rooms), 10-11 medium-temperature R290 coolers, and 10 R290 freezers.
Biedronka’s goal is to become 100% HFC-free in its supermarket refrigeration by 2025.
“It is still the majority of our stores [that uses HFCs], but I would say that we will soon come to a level at which we will have a 50-50 split,” Polak said.
Refrigeration is not the only element of the chain’s environmental program. “We understand our contribution to society in terms of environmental protection and in carbon footprint, so we are trying to do our best in every possible sector, not only in refrigerants, but also in food collec- tion, waste reduction, and shifting from plastics to other packaging,” Polak said.
One economic benefit of Biedronka’s retrofit program is the recovery and recycling of HFCs from the refurbished stores, which are then re-used in the stores that have yet to be converted. “The amount of the refrigerant which we recover during refurbishment gives us a base for servicing the stores that are still remaining,” Polak said.
This serves as a hedge against HFC price increases. “ We are really happy that a large part of our stores was based on natural refrigerants [when HFC prices began to go up] because they are the future,” Polak noted. “Nobody is resistant to an increase of a refrigerant price 10 times within a year, and that was the reality.”
Polak acknowledged that changing from HFCs to natural refrigerants has been a “significant investment.” In 2018, the chain spent 65 million euros (US$72 million) on refrigeration. But the additional expense has also been “partially justified by the higher energy efficiency,” he said, adding that the chain also benefits from the scale of its business. “So we’ve been able to drive the cost down to a reasonable level.”
Another challenge is Biedronka’s position as an early adopter of natural refrigerants in Poland. “I think that we underestimated, mainly in terms of CO2, that the technology is relatively young in the market, which has an impact on mainte- nance, especially in relation to brushless DC (BLDC) compressors, where the breakdown rate is slightly bigger than we expected,” Polak explained.
“We need to put a lot more focus on controlling, managing and maintaining it,” he said. “If you have one compressor, one breakdown, you can live with it, but if you have many thousands of stores, then it becomes visible.”
Polak was asked whether Cooling as a Service (CaaS) – a model by which end users essentially lease equipment rather than buy it upfront – would be helpful to a major user of transcritical CO2 like Biedronka. He said CaaS is not something Biedronka is planning to adopt. “CaaS is a very effective solution for entities where they need to balance properly their capital expenditure,” Polak acknowledged. But he added that adding “another stakeholder into the equation” makes it less effective since “everybody needs to make money.”
In addition, by using CaaS, “you impact your profit and loss more than you would just by depreciation,” Polak said.
Once Biedronka finds itself in a situation in which it will no longer be able to manage capital expenditures, “then we will look at it,” he said. “But as far as I know, we’re not at that moment yet.”
To Integrate, or Not To Integrate
A number of European retailers have been integrating refrigeration and air conditioning in the same transcritical CO2 system. But Polish retailer Biedronka prefers to keep things separate.
“It is fairly easy to adapt air conditioning and connect it to the refrigera- tion system, but then it is vulnerable to breakdowns and exposing your [store], and [making you] vulnerable to loss of goods,” said Wojciech Polak, Technical Director for Biedronka. “If you consider the breakdown rate in refrigeration and air conditioning separately, you have X amount of breakdowns on average, if you combine it together, you have twice as many.”
The risk of breakdowns is not the only issue keeping Biedronka from adopting integrated systems. Different optimal strategies for the two areas also play a part.
“From a thermodynamic perspective, there are different set points and require- ments for the refrigeration perspective and for the air conditioning perspective, which means that either you set it up for the reasons of refrigeration or for those of air conditioning,” Polak said. “Normally you do it for refrigeration, and air condi- tioning is not perfectly optimized consid- ering energy efficiency, so we’d rather keep it separate.”
This choice means that Biedronka does not expect to be HFC-free on the HVAC side by the time the refrigeration side uses only natural refrigerants. “We are actively looking for [natural refrigerant] solutions in terms of air conditioning,” Polak said. “I don’t think we will become HVAC natural in terms of the whole portfolio of stores that we have because there are no AC solutions available,” he said, though Biedronka is on the lookout for such solutions.