What Is the Most Sustainable Way to Make Coffee? The Answer Might Surprise You

What is the least sustainable way to drink your morning coffee?

Conventional wisdom might point to the disposable coffee capsules popularized by Keurig and Nespresso. Indeed, the city of Hamburg, Germany, went so far as to ban them from government buildings in 2016, as BBC News pointed out. However, it turns out that the carbon footprint of drip coffee is much higher, according to a new analysis published by the University of Quebec at Chicoutimi researchers in The Conversation. 

“Our research reveals that assessments based on a life cycle analysis, or the holistic vision, of products like coffee make it possible to challenge our intuitive reasoning, which is sometimes misleading,” the scientists wrote.

The researchers – Luciano Rodrigues Viana, Charles Marty, Jean-François Boucher and Pierre-Luc Dessureault – set out to calculate how four common coffee preparation methods contribute to the climate crisis. They looked at the entire lifecycle of each method, from the growing of the beans to the disposal of the coffee capsules and the washing of mugs. They then calculated the emissions associated with preparing 280 milliliters of coffee using one of four methods:

1. Filter coffee
2. Coffee capsules
3. French press
4. Instant coffee

What they found was that, when consumers followed instructions, instant coffee was the most sustainable method of coffee preparation and traditional drip coffee was the least. However, if coffee drinkers use 20 percent more coffee and heat twice as much water, capsule coffee rides into first place.

Why? Because actually growing coffee beans is the most carbon intensive part of the coffee-making process, accounting for 40 to 80 percent of a final cup’s emissions. This is because coffee growing has become a type of intensive agriculture that requires irrigation, nitrous oxide containing fertilizers and pesticides. Therefore, conserving coffee itself overrides almost all other sustainability concerns.

“At the consumer level, avoiding wasting coffee and water is the most effective way to reduce the carbon footprint of coffee consumption,” Rodrigues Viana, who is a doctoral student in environmental sciences, told The Washington Post. 

Capsules have an advantage over filter coffee in this regard because they inherently limit the amount of coffee that can be brewed. This saves 11 to 13 grams of coffee. 

“Producing 11 grams of Arabica coffee in Brazil emits about 59 grams of CO2e (CO2 equivalent). This value is much higher than the 27 grams of CO2e emitted for manufacturing of coffee capsules and sending the generated waste to a landfill,’ the study authors wrote. “These figures give an idea of the importance of avoiding overusing and wasting coffee.”

When it comes to brewing the most sustainable coffee possible, there are several nuances. For one thing, the source of your electricity makes a difference. In Alberta, which gets a lot of its electricity from fossil fuels, washing a coffee cup in the dishwasher is two grams more carbon intensive than making and landfilling a coffee capsule. In Quebec, because of its high percentage of hydroelectric power, washing the cup barely matters. If you have a high-carbon grid, keeping your coffee maker’s hot plate turned off and washing your cup in cold water can help.

The amount of coffee you drink matters too. One downside of coffee capsules is that their convenience might encourage people to drink twice as many cups, canceling out their advantage. 

One thing the study doesn’t mention is where your coffee comes from. Coffee is so carbon-intensive to grow in part because the traditional shade-grown method has been replaced by growing more plants under the sun. However, it is still possible to purchase shade-grown coffee, which can sequester carbon dioxide in the soil, provide habitat for birds and other animals and make coffee growing itself more resilient to rising temperatures, among other environmental benefits, as the Smithsonian’s National Zoo & Conservation Biology Institute pointed out. One way to improve your coffee sustainability is therefore to look for Bird Friendly coffee, which is both shade grown and organic.

Overall, the study is a good reminder that a product’s most visible environmental impacts to consumers are not necessarily the most significant. 

“As a consumer, what we’re left with is the visible waste in front of us, and that often tends to be packages and plastics,” University of Michigan School for Environment and Sustainability professor of sustainable systems Shelie Miller, who was not involved with the study, told The Washington Post. “But the impact of packaging, in general, is much, much smaller than the product itself.”

If you still want to reduce your coffee capsule waste, there are options.

“Reusable pods, if used for a long time, are a solution to reduce the amount of waste,” Viana told BBC News.