James Hamblin writes a long and fascinating article about the K-Cup in the Atlantic, which I have called design for unsustainability. We have been going on about them for years, fighting a losing battle pitting price and the environment against convenience. Even the K-cup's inventor complains about them, but notes that “It's like a cigarette for coffee, a single-serve delivery mechanism for an addictive substance.”
It's weird that people would pay the equivalent of $40 per pound for coffee that isn't even that good, yet "In 2014, enough K-Cups were sold that if placed end-to-end, they would circle the globe 10.5 times. Almost all of them ended up in landfills. They are not recyclable."
That's because they are composites of coffee, plastic and foil, and have to be separated by hand; it is just too expensive to do. It is done by Illy and Nespresso to make people feel better, but shipping pods across the country to make the world's most expensive compost out of the coffee and lawn chairs out of the plastic doesn't make a lot of sense. As for the people who try to separate the components themselves, there are not that many of them; if they are willing to do that they probably have the time and energy to make a real pot of coffee.
At TreeHugger we have never had anything good to say about coffee pods, ever. However Hamblin does point out that there are some benefits:
For one, pod machines save electricity in that they are not constantly working to keep a pot warm. And proponents of K-Cups argue that people are extracting coffee from the grounds more efficiently. “The 11 grams of grounds in a K-Cup are utilized more efficiently than when I throw a handful of ground coffee into my Melitta filter in the morning,” [Caffeinated author] Carpenter noted.
They are also more efficient in their use of water; " People who use single-cup pods are much less likely to brew more coffee than they actually drink."
I am not certain that either claim holds water; there are lots of one-cup coffee systems from french presses to my beloved Gaggia espresso machine where there is almost no waste of coffee or water. Not everyone is pitching out carafes of Mr. Coffee. But it is still worth a read at the Atlantic.