The environmental case for single-use plastic coffee pods
I often hear that single shot coffee capsules are not good for the environment, because of the energy to grow the beans, make the capsules, brew the coffee, and dispose of the waste. There is an upside however, as plastic capsules turn out to be a more sustainable way of drinking espresso than nearly any other method of making coffee. According to research, recyclable aluminium pods are more environmentally friendly however the lack of recycling facilities in the UK and the greater energy need to produce the aluminium pods means plastic capsules are better after all.
In the UK, nearly one third of households own an espresso pod machine. Green campaigners, have been critical of the rapid adoption of the coffee capsule, criticising the deluge of waste streaming from the pod-powered coffee makers.
It looks bad for the environment, but that’s not the whole story. To understand the environmental impact of feeding our coffee habit, it’s important to life-cycle assessment studies for the full range of coffee-making methods. Alf Hill, professor of chemical engineering at the University of Bath, looked at all the stages of coffee production, from growing the beans to disposal of waste, assessing the impact on ecosystems, climate change, and water.
His team found that instant coffee comes out best, but that capsules are the runner up in the environmental impact stakes. Filter or drip coffee comes third, while traditional espresso has the worst environmental impact. “The impact, such as greenhouse gas emissions, water and fertiliser use, mostly occurs where the coffee is grown,” says Hill. “Capsules tend to need less coffee input to make a single drink and so their overall impact can be lower even though we see more waste when we throw them away.”
Hill's research backs up other studies conducted during the past few years, which suggest that capsules are environmentally less harmful than alternative coffee-brewing methods. Aside from the environmental impact of growing beans in the first place, the second biggest hit is the energy it takes to brew coffee. That’s why barista-made espresso fares so badly in terms of its environmental footprint: a lot of energy is needed to brew just a tiny single espresso cup. Capsules, on the other hand, are more efficient. The coffee machines only flash-heat the amount of water needed for one portion, unlike, for example, boiling a kettle.
Typical users of a drip filter machine use it very inefficient often leaving it turned on, if more coffee is made than necessary. In that instance drip-filter coffee significantly worse than capsules!
Research by KTH in Stockholm, meanwhile, found that filter coffee has the worst environmental impact, because cup for cup, filter coffee uses more beans to prepare a single cup — about seven grams, compared to 5.7 grams for capsule coffee. Add that up to billions of cups of coffee drunk around the world each year and it quickly creates huge increase of the amount of coffee beans that have to be grown, harvested, processed and transported, plus all the energy needed to heat the water when making the cup.
Despite the many studies showing that drip coffee and espressos are actually worse for the environment than capsules, it is the lowly plastic coffee pod that gets the bad rap. People are just focussing on how capsules are killing the planet, hence the reason for a lot of work is going into making capsules more sustainable — because there is a sales opportunity in making them more sustainable, as people think they are bad — and not because it is actually an unsustainable way of drinking coffee.
A study by Quantis compared the electricity consumption during brewing, heating and wasting coffee for single-serve and drip coffee preparation. It found that single-serve coffee uses an exact serving of fresh coffee, which cuts coffee waste, while people making drip coffee often have leftover that they throw away. And espresso makers that sit on a gas hob or a hot plate use significantly more energy than a capsule machine does.
It is agreed that if aluminium capsules are fully and widely recyclable, they would indeed be better for the environment than plastic ones (even if plastic ones are also widely recycled). Having said that, the most recent Quantis research suggests that producing plastic pods uses less energy than making aluminium ones, so unless the latter are more widely recycled, then plastic capsules might come out better after all.
So what about the so called compostable capsules? The challenge here is they are rarely disposed of correctly. If you throw a compostable capsule into your green bin it will end up at the municipal incineration plant, there is no benefit to it being compostable. Producing the compostable capsule pollutes as much or even more than producing a plastic one. If it does end up in a landfill, it will degrade — producing methane that will end up in the atmosphere, creating more greenhouse gas.
However, if compostable capsules are not thrown away in the regular bin collection cycle but put into special bins that are taken to compost or, even better, to biomethanisation facilities, then they are better than aluminium or plastic ones (even if both of these are widely recycled), the problem is, currently it's rarely the case.
Of course, capsules being better than most other coffee-making methods doesn’t take away the fundamental fact that any product that generates waste poses an environmental problem.
Hopefully you have seen that it is more complicated and frightening than you thought. Every action and choice you make has consequences, both environmental and otherwise. It’s just a question of which lesser caffeinated evil you choose.