“At the consumer level, avoiding wasting coffee and water is the most effective way to reduce the carbon footprint of coffee consumption,” said Luciano Rodrigues Viana, a doctoral student in environmental sciences at Chicoutimi and one of the researchers who conducted the analysis.

How you make coffee matters

The environmental impact of coffee is heavily influenced by how people prepare their drinks, Rodrigues Viana said.

For example, in the case of instant coffee, if you use 20 percent more coffee and heat twice the amount of water, which often happens, then the data suggests coffee pods might be the better choice.

Meanwhile, coffee-pod machines are typically designed to use the ideal amount of coffee and water, leading to less of both being wasted. Compared to traditional filter coffee, drinking about a cup of the beverage brewed from a pod saves between 11 and 13 grams of coffee, the data shows.

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“Sometimes it’s really counterintuitive,” said Andrea Hicks, an environmental engineering expert at the University of Wisconsin at Madison. She conducted a similar analysis comparing different brewing methods, and also found pods had less environmental impact than the conventional drip filter method, and in some cases were better than using a French press.

“Often people assume that something reusable is always better, and sometimes it is,” Hicks said. “But often people really don’t think about the human behaviour.”

For instance, the latest analysis found the benefits of pods can be lost if their convenience encourages people to drink two cups instead of one.

There are other factors to consider: How your electricity is generated plays an important role, Rodrigues Viana added. A cup of coffee prepared using electricity mostly generated by fossil fuels produces about 48 grams of CO2 equivalent, the analysis found. In comparison, a cup made using primarily renewable energy emits roughly 2 grams of CO2 equivalent.

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And other research has shown that adding milk can “drastically increase” the overall carbon footprint per serving.

Don’t fixate on packaging

To be sure, producing and discarding pods can have an impact on the planet. But studies show that the lion’s share of the environmental effects of drinking coffee come from producing the beans and the energy needed for brewing.

“Regardless of the type of coffee preparation, coffee production is the most GHG-emitting phase,” Rodrigues Viana and his fellow researchers wrote. “It contributed to around 40 percent to 80 percent of the total emissions.”

Packaging accounts for a much smaller share, the data shows. Here’s the math for pods: Manufacturing them and sending the used ones to a landfill generates about 33 grams of CO2 equivalent. Producing 11 grams of Arabica coffee in Brazil - the amount that can be saved by using a pod rather than brewing filtered coffee - emits close to double that amount: about 59 grams of CO2 equivalent.

But if you want to help reduce the impact of packaging, you can recycle used pods or switch to reusable ones.

Bottom line: Be mindful

All that said, the first thing to do might be to ask yourself if you actually want that cup of coffee and whether you’re going to drink all of it, Miller said.

“There’s not necessarily a really easy rule of thumb to tell consumers, ‘Here’s the best environmental option,’” Miller said. Instead, she recommends focusing on reducing waste and consumption overall and trying to be as efficient as possible with the resources you have.

“It really comes down to being mindful about the products that you consume and trying not to waste our products,” she added.

The Washington Post

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