Reading Time: 6 minutes – Cover photo: osde8info on Flickr[br]
Cutting carbon emissions is important to many people, and ditching paper seems like an easy way to do your bit – but do short lifespan consumer electronics really have a smaller carbon footprint than paper?
It’s 2020. The world is warmer than ever, Australia has seen its worst ever wildfires, and we are just years away from a critical turning point after which the effects of climate change will be hardest to combat. Climate change sucks.
Saving every last gram of carbon is at the front of people’s minds. But while working electronically might seem like it’s more eco-friendly due to the paper savings, electronics require the mining of rare minerals and greenhouse gas-intensive manufacturing, all while having an intended lifespan of only two to three years.
It certainly isn’t a guarantee that paperless working is more eco-friendly than paper. Keep reading to see a breakdown of some common statistics and ways you can calculate whether or not using a tablet would be more eco-friendly for you!
Carbon Footprint Statistics
First off, we’re going to need some stats. Skip this section if you aren’t interested in my methodology!
Finding the carbon footprint of various modern tablets isn’t too hard, and we can get some pretty good estimates. For instance, the 2018 iPad has a carbon footprint of 98kg, while a Microsoft Surface Pro 5 has a carbon footprint of 121kg. Sadly, Samsung doesn’t publish any statistics on the carbon footprint of their devices and they could be higher than both of the above, but that at least covers two out of the three largest tablet manufacturers.
We can also consider the carbon footprint of charging the tablet’s battery. In the UK, 1kWh of energy produces 282g of carbon emission, meaning that a full charge of a 2018 iPad (33Wh) and a Surface Pro 5 (45Wh) produces 9.31g and 12.7g of CO2 respectively. In the US, 1kWh of energy produces 448g of carbon emission, bumping it up to 14.8g and 20.2g of CO2 emission respectively. Most (western) countries’ CO2 per kWh emissions fall within the range of the UK and the US. Going forwards, assuming you charge your tablet fully 100 times a year, this adds 931-1480g or 1270g-2020g to the carbon footprints of 2018 iPad and Surface Pro 5 users respectively per year.
Unfortunately, estimating the carbon footprint of paper is a more arduous task – has the paper been recycled? Will it be recycled? How thick is it? How sustainably was it sourced? I found a 2012 study by the American Forest & Paper Association that estimated paper’s carbon footprint at 8.5g per sheet, assuming 72% of it is recycled (which is typical for US offices). There were a number of other studies that came up with similar numbers but I think this one had the best methodology, so we’ll carry this number forwards but with a big 50% errorbar because this is a difficult thing to estimate.
I’m going to assume that the carbon footprint of the printer and the ink is negligible compared to that of the paper – or at the very least, it’s a lot smaller than the existing error bars. Printers have long lives and are used by many people. Also, there’s probably already a printer in your office – so I don’t think the paper figures should include the carbon footprint of manufacturing the printer, as it already exists for you to use (unlike a tablet, which would have to be bought new and would be just for your use.)
A Sliding Scale of Answers
How many sheets of paper do you use per year? It’s a hard question to answer! I’ll break down paper use into three sources: printing papers, textbooks and note taking. Anything else (like printing a plot occasionally to take to a meeting) is negligible in comparison.
We’ll consider three examples: a “typical” paper user, a “careful” paper user and a “heavy” paper user. These examples are based on the PhD students around me in astronomy. An average researcher in another field could fall well outside all three.
Our typical paper user prints out about one important paper to read per week (50 per year). Each paper has about 20 pages (and is printed double-sided, using one sheet per two pages.) They buy one 300 sheet textbook every two years, and make two pages of notes each day for 230 working days a year (46 weeks x 5).
Our careful paper user prints out one 20 page paper per week, but they print two pages per side and squint to save on paper. They do not buy textbooks and make one page of notes each day for 230 working days a year (46 weeks x 5). (Their Twitter handle is @Olippolar, and we talked about her careful paper use on the bus in January.)
However, our heavy paper user prints out two 20 page papers per week. They print only one page per sheet (single-sided) so that there’s more space for scribbling and notes. (Alternatively, this is equivalent to printing out four papers per week but double-sided.) They buy one 300 sheet textbook per year and make three pages of notes each day for 230 working days a year (46 weeks x 5).
Even within some very liberal error bars, only the heavy paper user comes close to the carbon footprint of electronic devices. Typical and careful paper users need not worry – despite the stigma of printing, they’re probably at least three times more eco-friendly than tablet users.
A Note on the Biggest Sources of Carbon
The above results suggest that paper gets a bad reputation as a source of carbon. It’s targeted as an easy thing to cut down on – and rightfully so if you compare the huge difference in carbon footprint of a heavy and a careful paper user – but it still doesn’t match the huge emissions of making electronic devices.
Going paperless is often mis-sold to consumers as a way to be more sustainable. In reality, you’d need to be chugging through paper (or not bothering to recycle any of it) for going paperless to be worth it for you.
However, I’d like to draw your attention to the fact that this is all a moot point. Consistently, the largest sources of your carbon footprint are transport, electricity, food, and air travel. An average American contributes 16.2 tons of carbon emissions per year, which is equivalent to the carbon footprint of a whopping 1.9 million sheets of paper.
If you’d like to significantly alter your carbon footprint, then you really ought to do one of the following:
- Have your heating set lower (18°C/64°F) in the winter and your air conditioning set higher in the summer. It shouldn’t be on when you aren’t in the house. Installing a programmable thermostat would help to make a big difference here. Heating can have a phenomenal carbon footprint when done inefficiently.
- Walk, bike, or use public transport whenever possible. Only use a car when it’s absolutely necessary.
- Cut down your consumption of meat (especially beef) and animal products. Going completely vegan would halve your food-related carbon footprint. One 170g/6 ounce beef burger emits 6.1kg of CO2 during its production, which is the same carbon footprint as 720 sheets of paper. (Source)
- Fly as little as possible. If you’re a senior researcher who is constantly going to far-away conferences and meetings, then this especially applies to you! Could your trip be replaced by some telecons?
If you want to be more eco-friendly, then going paperless has a minimal (and probably negative) effect on your carbon footprint. But even then, it’s a drop in the water compared to the main sources of greenhouse gas emissions in your life – like heating, transport and food – so I don’t think you should be put off from using a tablet even if it will increase your carbon footprint a little bit. If you look after the device and keep it for much longer than its intended life then it would at least match the carbon footprint of using paper.
Curious about going paperless? I’ve written lots of other articles on the subject, like recommendations on the best tablets for researchers or citation managers you could use to keep track of your electronic paper library.