You Can Now Calculate Your Grocery List's Carbon Footprint

March 13, 2023 11:20 AM EDT

What if we could pick up a bag of chips at the grocery store, and know, just by looking at the label, the climate impact as well as the calorie count? We aren’t there yet—at least not for most products in the United States—but a new web-based tool released by Swedish climate intelligence company CarbonCloud is bringing us closer to being able to calculate the greenhouse gas emissions of a grocery list as easily as we would the nutrition values. It’s not quite ready to launch the carbon-counting revolution, but it is a start.

To test it out, I volunteered to run my editor’s weekly shopping list through the database and, by selecting the products and brands with the lowest emissions, ended up saving her the equivalent of 83.8 kg of CO2, about the same as driving a gasoline-powered car for 208 miles. And she still gets to eat Ben & Jerry’s for dessert, as long as she chooses the non-dairy Half Baked ice cream (2 kg CO2 per kg of ice cream) over regular Chocolate Chip Cookie Dough (4 kg CO2/kg). (A pint of ice cream is about 0.25 kg)

When I was a kid, my parents based my weekly allowance on the money I saved them by clipping coupons. Too bad I can’t convert carbon emissions savings into a raise. At this point in the website’s development, it’s about the only way it would be worth going through the cumbersome process again, even if it helps with climate change.

Food and agriculture are responsible for nearly a quarter of global emissions. But unlike electricity generation (25%) and transportation (14%), little has been done to reduce the climate impact of what we eat. Yet doing so is vital: a recently published study in Nature Climate Change found that our current food system could add 1°C in global warming by the end of the century, propelling us well past the 1.5°C (2.7°F) limit that helps us avoid the worst effects of the climate crisis.

Consumers could play a significant role in pushing food companies to reduce emissions by choosing low- or net-zero carbon products, but not without data, says David Bryngelsson, CarbonCloud’s CEO and founder. The confusion stems from a food industry rendered inscrutable by multiple layers of suppliers—a microwavable frozen pad thai meal, for example, could have a dozen or more ingredients, each sourced from a different state, or even country, each producing varying amounts of emissions. Quantifying them all requires a climate scientist’s expertise; comparing one microwavable meal against another requires a standardized system of assessing impact. While most food companies publish emissions data in the fine print of their corporate sustainability reports, few consumers are going to take the time to parse the details and choose accordingly.

Now they don’t have to, according to Bryngelsson. CarbonCloud has just released its free searchable database online, listing the carbon footprint of 10,000 branded food and beverage products found on American grocery shelves, ranging from Campbell’s Soup to Lipton tea, Barilla pasta and Tyson packaged meat. Each item on their ClimateHub website has a total emissions by weight tag; consumers looking for more details can click through to find out what percent of emissions come from transport, packaging, processing and agricultural practices or, in some cases, dig even deeper to look at sourcing and emissions at the ingredient level. “We start with the consumer because they feed money into the food supply system,” says Bryngelsson. “They need to start making informed choices, and if those choices lean towards better climate performance, the incentive is there for the food producers to start differentiating themselves. That’s what we’re after.”

The idea is not exactly new—the world’s first carbon label, introduced by the Carbon Trust, debuted in a U.K. grocery store chain in 2007 with tags on everything from sugar to laundry detergent and toilet paper. But the program fizzled out a few years later due to poor uptake and low consumer interest. That is starting to change, says Bryngelsson. Consumers are much more climate aware than they were a decade ago—a 2020 survey commissioned by Carbon Trust and conducted by YouGov found that two thirds of consumers in the U.K., U.S., and multiple European countries support carbon labeling on products. Several companies, such as oat-milk innovators Oatly, are already affixing their own labels to get ahead of the trend.

CarbonCloud got its start helping companies like Oatly, Dole, and baby food maker Little Freddie assess their own carbon impacts. That expertise forms the basis of ClimateHub’s dataset, says Bryngelsson, who worked on carbon accounting methods as a researcher at Sweden’s Chalmers University of Technology before going on to found CarbonCloud. “We know the impacts of different agricultural products in different regions. We know what electricity systems look like, we know what transport routes are usually taken, and which vehicles are used.” By breaking supply chains into modules, and then plugging in publicly available data for each sector, he has been able to estimate the total emissions of tens of thousands of products in the U.S. and Europe.

In aggregate, it could be a powerful tool for greenhouse gas reductions—CarbonCloud claims to have the largest food emissions database in the world, which, if widely adopted by climate-conscious consumers, could force change in the industry. “Once you start labeling things, consumers are going to demand more accountability and lower carbon footprints,” says Bryngelsson. That may be the case. But a closer examination of the dataset shows that it’s not exactly ready for prime time.

I looked up every item on my editor’s list with an eye towards minimizing carbon emissions whenever possible. “Coffee creamer” had several options, from whole milk (2kg CO2/kg) to several brands of oat and nut milk alternatives (0.6 kg CO2/kg). So far, so obvious: it is well known that meat and dairy products have a much higher climate impact than plant-based items. But the entries for non-dairy flavored creamers, like butter pecan or hazelnut, took me by surprise, clocking in at 20 kg CO2/kg. When I clicked through for details, it was frustratingly scant, only listing that 99% of the emissions came from agriculture. It was only by researching the ingredient list on the creamer company’s own website that I began to grasp the reason for the disparity: the main ingredient is palm oil, a big climate offender due to deforestation.

And while Bryngelsson’s goal for ClimateHub is to get companies to compete on lowering impacts, most food items shared the same emissions across categories: pasta, no matter the brand, nets 2 kg of CO2/kg. So too do granola and salsa, regardless of whether or not they are organic, which would, presumably, have an impact in lowering the use of high-emissions fertilizer. If Chobani’s blueberry flavor Greek yogurt (2 kg CO2/kg) emits the same amount of carbon equivalents as rival Danone’s, it’s hard to see the incentive for either company to change the status quo. Bryngelsson disagrees, citing surveys showing that consumers are more likely to think positively about a brand that could demonstrate it had lowered the carbon footprint of its products, and that they are also willing to pay a small premium to buy it.

The category-wide standard emissions are a starting point, says Bryngelsson. The next step is for individual companies and suppliers to weigh in with their own reduction efforts, whether it be electrified transport, a renewable energy source or recycled packaging. “We can produce zero carbon food. But we need 1,000 little business decisions and innovations to get there,” he says. “By making this information available, we will get that movement going.” Those actions can be made visible to consumers by plugging them into the supply chain module on a per-product basis, reducing the overall emissions total. To do so, companies must subscribe to ClimateHub, starting in the low hundreds of dollars a month per listing. So far, only a few have done so, but Bryngelsson is expecting more uptake now that the dataset is public.

It took me more than an hour to go through the 20-odd items on my editor’s grocery list in order to find the lowest possible emissions via ClimateHub’s dataset, and the process was both frustrating—the search function is basic at best—and enlightening. Frozen, farm-raised skinless salmon filets, at 10 kg CO2/kg, are a much better climate buy than their wild caught pacific salmon cousins at 60 kg CO2/kg. It’s better to buy a Starbucks cold-brew (2 kg CO2/kg) than a pumpkin-spice latte (10 kg CO2/kg). I can recommend Frito-Lay Spicy Nacho tortilla chips (4 kgs of CO2/kg) over Doritos at 7 kg CO2/kg, but I still can’t tell what sets them apart. I want the system to work, but I can’t imagine the average grocery-store customer doing this much homework just to reduce the impact of dinner.

There are scores of organizations like CarbonCloud promising to help companies calculate their carbon footprint, and just as many apps and websites offering consumers a way to shop better. But the data sets and calculations vary widely. CarbonCloud may come closest to a standardized method of assessing carbon emissions of our food products, but ultimately the only thing that is really going to make a difference in the average 13 seconds a customer spends choosing a grocery store item is by posting a clear climate label on the products.

Correction May 15, 2023

The original version of this story misspelled the name of an oat milk brand. It is Oatly, not Oatley.

You Can Now Calculate Your Grocery List’s Carbon Footprint

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