If you drink one of the 2bn cups of coffee consumed each day worldwide, you may have seen headlines last month celebrating the coffee pod, a single-serving container – typically made of plastic or aluminum – that can be inserted into a machine to brew a cup of coffee.
New analysis found that coffee pods may be more environmentally friendly than filter coffee, making headlines in the Washington Post and the BBC. But could it really be true? Some experts and coffee enthusiasts questioned how good for the planet pods actually are, especially given the waste that coffee capsules notoriously produce. But some scholars maintain that – even though it’s important to consider how capsules are disposed of – most greenhouse gas emissions happen while coffee is being grown. So reducing how much coffee you use, even if that takes using a coffee pod, can decrease the emissions of your coffee habit.
“It hurts to know that we create so much waste,” Luciano Rodrigues , one of the researchers behind the new study and a doctoral student in environmental sciences at the University of Quebec at Chicoutimi, said in an email. But even if there were no coffee capsules in the world tomorrow, abandoning them “would make no contribution to reducing greenhouse gas emissions”.
The original analysis
Last month, a team of researchers at the University of Quebec at Chicoutimi published an analysis looking at the greenhouse gas emissions associated with making a cup of coffee four different ways: with a French press, instant coffee, filter or single-serving capsule. What they found surprised many readers. In certain cases, a traditional filter coffee machine can produce 1.5 times as many emissions as a coffee pod, despite the aluminum or plastic waste users are left to toss in the trash.
That’s because “coffee capsules avoid the overuse of coffee and water”, the article’s authors write, by precisely measuring the correct amount of ingredients. Left to measure on their own, many coffee drinkers use 20% more coffee and twice as much water as is actually needed to brew a cup of filtered coffee. And growing that extra coffee emits more greenhouse gases than manufacturing and throwing away coffee capsules, the analysis found.
Producing 11g of Arabica coffee in Brazil – the amount that can be saved by using a coffee pod – emits about 59g of CO2 equivalent, about twice as much as the 27g of CO2 equivalent emitted by creating and disposing of those same pods.
It makes sense that we intuitively think “pods are obviously worse for the environment because we use them and throw them in the waste”, but that “using double the amount of coffee to make a filter coffee is not a problem”, said Viana. But the work that goes into producing coffee beans is actually “much more polluting”. The difference is that consumers don’t see it.
However you prepare your coffee, the production of the coffee beans is the most greenhouse gas-emitting phase in the coffee lifecycle, contributing between 40% and 80% of coffee’s total emissions. That’s a result of how the agricultural sector uses intensive irrigation, fertilizers and pesticides to increase the yield of coffee plants – and contributes to vast deforestation in the countries where coffee is grown.
What do other scientists say?
Viana said he wasn’t surprised by his team’s findings, but was surprised by the media attention they received, because “we are not the first to report similar findings”.
The Conversation – where the article was originally published – is a nonprofit newsroom focused on sharing academic stories with the general public, but is not an academic or scientific journal. Viana expects that he and his colleagues will publish a peer-reviewed paper on the same subject later this year. But the results are hardly new: an engineering professor at the University of Wisconsin-Madison conducted a similar analysis in 2017, and a team of Swiss researchers published similar results in 2007.
Although most researchers agree that coffee pods produce fewer emissions than filter coffee, that’s not to say there aren’t other, more environmentally friendly ways of making a cup of coffee – or that the impacts of coffee pods are equal in every city or country.
In 2021, a team of Italian researchers found that using a Moka pot, a stovetop coffee maker popular in Europe and Latin America, can produce significantly fewer greenhouse gasses than a capsule. (The study said that because of the extra packaging and post-consumer waste disposal, “the preparation of a cup of coffee with a coffee with a coffee pod or capsule machine would result in extra emissions of 27.6 or 12.6g CO2e with respect to those emitted with an induction Moka pot, respectively”.) Even the Canadian team’s analysis found that instant coffee had fewer emissions.
Mauro Moresi, an engineering professor at the Accademia dei Georgofili and one of the researchers on the 2021 Italian study, agreed that in all cases he and his team examined, “the coffee bean cultivation and green coffee production phase represented the primary hotspot.” He notes that production-related emissions can vary from country to country, depending on how vast the scale of deforestation for example, so it’s important to consider where your coffee comes from.
But the waste!
Just because capsules produce fewer greenhouse gases than filtered coffee doesn’t mean the waste they produce isn’t a problem, says Viana. Globally, coffee capsules make up about 576,000 metric tons of waste. The number of Keurig cups alone thrown away in 2014 could circle the earth 12 times.
Studies like the one Viana and his team are conducting are important, says Andrew Gray, an assistant professor of watershed hydrology at the University of California-Riverside. “It’s just that, oftentimes, researchers seem to tend to focus in on using one of these kinds of indices for environmental or climate impact – like CO2 emission to the atmosphere – and then potentially overlook other kinds of potential impacts on the environment – like the production of pollution, in this case, plastic pollution.”
“A hallmark of the era that we’re living in now, and have been living in for the past couple of decades, is the increasing use of plastic for lots of single-use applications,” said Gray. “Plastics, for a long time, have been thought of as inert substances,” but scientists are starting to increasingly understand their potential impacts on human and animal health, as carcinogens and endocrine disruptors. “There’s lots of potential cause for concern, especially since we’re finding microplastics everywhere.”
The impact of packaging waste “is quite complex and varies according to the disposal scenario used on a local or national basis”, said Moresi. While Keurig Dr Pepper uses plastic derived from fossil fuels to manufacture its pods, Nespresso produces capsules made out of aluminum, which can be recycled in some, but not all, cities. And just because coffee pods can be recycled doesn’t mean they always are – one study found that only 11% of capsules were recycled in Brazil in 2017. That’s why some cities, like Hamburg, Germany, have banned coffee pods.
In an attempt to combat that, the Swiss company Migros launched a new “coffee balls” machine late last year. Instead of using plastic or aluminum, Migros’ coffee balls are coated in a seaweed-based covering, which it says makes the balls fully compostable.
Viana explains that coffee could become one of the “main victims” of the climate crisis, as the amount of the world’s land area suitable for coffee production diminishes. It’s key, he and his coauthors write, that coffee producers and suppliers “take action to reduce the environmental and social impacts of coffee production”.
