Supermarkets are tackling emissions from their freezer aisles

Snaking through every American supermarket are miles of refrigerator piping, keeping unsold food cold in the fridges of the dairy, meat and frozen food aisles. Those pipes contain some of the most potent global warming chemicals produced by any industry on earth. The hydrofluorocarbons (HFCs) within them are typically between 1,400 and 4,000 times more powerful as greenhouse gases than carbon dioxide.

The pipes are supposed to be vacuum-sealed. But they are often imperfect: The average U.S. supermarket leaks up to 25 percent of its refrigerant gases into the atmosphere, according to the Environmental Protection Agency. A single supermarket can emit as much as 875 pounds of HFCs a year — that’s the CO2 equivalent of 300 cars, according to Avispa Mahapatra, climate campaign director at the Environmental Investigation Agency.

“In a world [where] we’re trying to do everything we can to not use greenhouse gasses, these [HFCs] are so entrenched in our economy,” said Mahapatra. “And we’re using other fluorochemicals to produce [HFCs]. It’s a chemical nightmare of emissions.”

The good news is that a solution to the HFC problem has slowly begun making headway at Aldi, Walmart, Albertsons and other big-name retailers. Increasingly they are using natural refrigerants — ammonia, CO2 and propane — which are magnitudes less damaging to the atmosphere than HFCs. 

A solution to the HFC problem has slowly begun making headway at Aldi, Walmart, Albertsons and other big-name retailers.

Each chemical refrigerant carries a “global warming potential” (GWP) rating. GWP is an index in which a chemical’s greenhouse potency is scored as a multiple of CO2, which is ranked at one. The GWPs of ammonia, CO2 and propane are zero, one and three, respectively. For comparison, fluoroform has a GWP of 14,800.

Aldi, the leader in this space, has 590 stores that use refrigerants with a GWP near zero. It has committed to transitioning all of its U.S. stores to natural refrigerants by 2035. Aldi “is showing the market that this is no longer a bunny-hugger wishlist item out there,” said EIA’s Mahapatra. “It’s technologically possible and [they’re] doing it without cutting into their profits.”

“[Aldi is] growing at an unprecedented rate,” said Amber Hardy, director of systems and sustainability at Aldi US. “The goal was to find a way to minimize our carbon emissions and minimize our impacts with our growth and expansion. And one of the most important steps to that was refrigeration systems for those new stores.” Aldi is also going to be remodeling older stores to get those on lower climate impact refrigerants.

Walmart has also pushed to clean up its act after a report from the EIA found that 60 percent of the Walmarts visited showed leaks. Its goal is to transition to low-impact cooling in all stores, distribution centers and data centers by 2040. In 2022 the company opened its first U.S. store using CO2 in New York.

Publix planned to install CO2 systems in five new stores in 2022 and replace an HFC system with a CO2 one in an Atlanta location.

Albertsons is also moving to natural refrigerants. After a compliance settlement in 2021 with the California Air Resources Board for $5.1 million, the company started its Recipe for Change sustainability initiative in 2022. That same year the company transitioned 85 stores to lower-GWP refrigerants (notably not always natural ones). It has three stores using CO2 systems. While the grocer has not committed to use all-natural refrigerants by a certain date, it is aiming for a 47 percent carbon reduction in its operations by 2030 and net zero emissions by 2040.

Most U.S. companies are still in the early stages of moving to natural refrigerants. Here are four things grocers should start doing to hasten the transition:

1. Start collecting metrics

One of the biggest challenges with refrigerant emissions is that for years it has been cheaper to simply buy more chemicals than to fix leaks. Albertsons’ strategy for dealing with that is to connect the refrigerant emissions problem to the day-to-day operations of the store, such as the loss of sellable products.

“From a financial standpoint, it’s not just we had to pay a technician to come out [to fix the leak] and pay for additional pounds [of refrigerant], but there’s also loss of product and a negative impact on the customer experience,” said Charissa Rujanavech, Albertsons’ senior director for climate, circularity and innovation.

“We use a whole host of metrics to assess and prioritize which systems to replace first,” she said. By giving leaks the same level of cost-importance as shoplifting or spoiling, Rujanavech is hoping she can get managers and employees to understand the importance of tackling leaks early, and therefore get better at tracking them.

2. Make it the standard for any new store

Transitioning to natural chemicals is a huge expense. Natural refrigerants, unlike HFCs, have to be pressurized or are flammable. New systems must be made both safe and effective. It can cost $3 million to retrofit a store, give or take a few million. That comes with significant downtime as miles of piping are ripped out to be replaced by new equipment. For many, that’s just a complete no-go from a business perspective.

“They’re in a really difficult position,” said Morgan Smith, program and communications director at the North American Sustainable Refrigeration Council (NASRC), a trade group working to help grocers transition to natural refrigeration. “If [they] really want to be future-proofed with the most climate-friendly options, they have to rip out all their existing refrigeration systems and put in a whole new one.”

Many grocers have turned to gasses with lower GWPs even though they are still HFCs. Low-rated HFCs are a drop-in solution because they require only minimal work to make the switch. While replacing an HFC with a GWP of 4,000 for one ranked at 1,400 is progress, it’s still magnitudes worse than a non-HFC solution.

Starting with a natural refrigerant system when building a new store is a much easier sell to executives than shutting down an entire store to do a retrofit. Mahapatra says that if you don’t want to redo the store in 10 years because sourcing HFCs has become difficult because of regulation, it just makes sense to start with a natural system from the beginning.

And most refrigeration systems have lifespans of about 15 years. They have to be replaced eventually. “With money from the loss of energy and from the loss of refrigerant, we might as well replace it with something that is more energy efficient, that is less leaky, and that in the end saves us money,” Mahapatra said.

3. Invest in new training for technicians

Europe has a lesson for U.S. grocers on the transition to natural refrigerants: Train technicians on the new equipment as soon as possible in order to avoid bottlenecks later. By 2015, two-thirds of grocers in Europe were using natural refrigeration. The conversion was slowed, experts say, because the European market didn’t have enough professionals to install or maintain the new CO2 systems.

Even grocers switching to less impactful HFCs are going to have to move away from them soon.

In the U.S., only 2 percent of grocery stores are HFC-free, according to Smith. But that will change quickly, increasing demand for workers with natural refrigerant skills: NASRC expects CO2 systems in stores to grow by 313 percent between 2023 and 2027.

In the U.S., few community colleges offer courses on CO2 or propane, according to Bryan Beitler, a technician with 45 years of experience and the current president of NASRC. “The trainers who have to administer the curriculum, they don’t have CO2 experience,” he said. “So we have to elevate their knowledge to get them comfortable with training a class of students on the topic.”

The NASRC has obtained grant money to install two CO2 systems for training purposes in its Dallas and Southern California training centers. Some grocers are discussing a collaboration to fund a training program but Beitler declined to confirm their names.

4. Stop using the EPA as an excuse

In 1994, the United States banned chlorofluorocarbons (CFCs), the chemical used commonly in refrigerators at that time. The ban stopped and reversed the depletion of the ozone layer, which protects life on earth from the harmful effects of excessive ultraviolet sunlight. It forced companies to replace their CFC technology with alternatives within 13 years. The policy became a symbol of the Environmental Protection Agency’s power to positively affect the climate.

But there is no outright ban on HFCs. Since that landmark action against CFCs, the movement to remove harmful refrigerants from the frozen food aisle has instead become decades of cycling from one new, supposedly less impactful HFC to another. 

This period of procrastination is coming to an end, however. In 2020, the U.S. signed the American Innovation and Manufacturing (AIM) Act into law which gave the EPA the power to create new regulations that could reduce HFCs over a phased period through 2036, without banning them completely. 

The days are numbered for HFCs, anyway. California is making it harder to purchase high-GWP refrigerants and set a goal for California to be fully transitioned off HFCs by 2035. In New York, the Climate Leadership and Community Protection Act passed in 2019 requires New York to reduce HFCs and all other greenhouse gasses 40 percent by 2030, and 85 percent by 2050. It has prohibited the sale of equipment that uses high-impact HFCs starting this January. In 2025, Washington also plans to ban the sale and purchase of certain HFC refrigerants with high global-warming potential for non-essential consumer products. So even grocers switching to less impactful HFCs are going to have to move away from them soon.

“With these regulations, those refrigerants just aren’t really going to be viable in the long term,” Smith said. “Really what they are is an interim solution.”