The Search for a Sustainable Coffee Mug

Have you ever noticed the person standing in front of you at your regular cup of joe establishment pull out a stainless steel mug to be used instead of being given a disposable paper cup? If so, and if you’re anything like me, the thought may have crossed your mind as to how environmentally friendly is it really is to save the 10 cents off your coffee.

Travel mugs, cups, tumblers...ect come in various shapes and sizes, but more importantly in various materials. The usual options available to us and the energy used to make them are shown in the table below:

A striking difference in energy can be seen, with a stainless steel mug requiring 82 times more energy to make than your average disposable paper cup. If we look at carbon emissions from manufacturing the cups for different materials in the table below, we see the same relationship, with stainless steel having the largest carbon footprint and a disposable paper cup having the lowest.

By adding the energy used in manufacturing reusable cups and the energy used in washing them after each use, we can determine that you would have to use a stainless steel cup 197 times to make its carbon footprint equal to using one paper cup.

So, you would need to use the stainless steel mug once a day for at least seven months before it had a smaller footprint than the paper cup. Reusable plastic cups are found to be the lowest-carbon option, requiring only 40 uses to equal the emissions from one disposable paper cup. Selecting a cups that is made from 100% recycled plastic would further improve its environmental benefits.

Whichever you choose, the conventional wisdom that multiple uses of the same cups will produce a lower overall environmental impact still rings true. Then again, in our own lives how many of us have multiple stainless steel mugs that are unused at home, and how many of us have on the odd occasion used a paper cup, while owning a reusable mug? As with any analysis issues arise with what factors you choose, the benefits of using a reusable cup vary quite a lot. In this case they depend on factors like durability of the cup, weight and the energy used in washing it.

You can help minimize your impact from all those Starbucks and Timmy’s visits by not just choosing a reusable mug with a small carbon footprint (reusable plastic mug in this example), but using that mug as much as possible, and making sure you wash it as efficiently as possible. The choices we make in our daily lives can collectively make a substantial difference to our carbon footprint. Deciding what to choose isn’t always as simple as we first assume.