The Answer: Paper books.
E-readers have come a long way in usability and comfort. With features that make it easy to read on the beach or in the dark, go online or hold hundreds of volumes, they’re trying to outdo the good old paper book. While many readers have a clear use preference between the two, we wondered how the comparison holds up on a sustainability level. We compared paper books and e-books to see which is more green.
How We Measured It
Our metric for comparison is the carbon dioxide equivalent emissions (CO2 eq.) resulting from the reading habits of the median American reader. We considered the full lifecycle of reading paper and electronic books: materials, manufacturing, transportation, use, and end-of-life.
To make a valid comparison, we need to evaluate both options with a consistent scenario, known as a functional unit. Our functional unit will be the number of books the median American would read in the amount of time an e-reader is typically kept before being replaced. The median American reader finishes 8 books per year. For now, we’ll assume that all of these books were newly purchased, and not borrowed from a library or from a friend. As for the e-reader (tablet), our sources indicate the average unit is replaced about every 2.5 years. Therefore, our functional unit for comparison is 8 books per year x 2.5 years = 20 books.
Few consumer electronics companies release lifecycle data for any of their products, including e-readers, with the notable exception of Apple. Because of the availability of data, our analysis uses the iPad Air as our e-reader device. Considering every phase except the use phase, the device emits 178 kg CO2 eq. The average book, in contrast, emits only 4 kg CO2 eq. per book across all of its lifecycle phases. For 20 books, that’s a total of 80 kg CO2 eq.—less than half the emissions from the e-reader.
It’s also important to note that most of the net emissions from producing books (about 45%) results from the loss of carbon storage capacity that trees provide. If the land is reforested, much of this carbon storage capacity can be returned, decreasing the net impact even more.
But don’t forget about transportation, or where you’re getting your book or e-reader, because the impact of traveling to the store in this case is bigger than the impact of what you’re buying. Burning a single gallon of gasoline in your car emits about 9 kg of carbon dioxide. This means that the impact of driving 5 miles to a library or bookstore and back has equivalent emissions to the production of the book itself. From a carbon emissions standpoint, borrowing a book (two round-trips in a car—one to borrow and one to return) may be worse than buying a book from the bookstore (one round-trip in a car to buy the book). Both are less sustainable than buying the book online and having it delivered to your doorstep. The best scenario may be biking to pick up your book, or, if you choose to drive, combining your trip to the library or bookstore with other errands.
Now we know how to make paper books even less impactful. But before guilt sets in as you glance over at your e-reader, consider cases in which the e-book would be the way to go:
If you’re a big reader clocking in more than 20 books a year, the e-reader might be the better choice, since its impact per book decreases the more you use it.
If you read e-books on a device that you would have purchased anyway for other uses (think about everything you might use that iPad Air for), e-books are the way to go. Many readers of e-books use a dedicated e-reader (41%), but if you’re one of the people who reads on a computer (42%), cell phone (29%), or tablet computer (23%), the huge, upfront impact of manufacturing the device is shared amongst all those other uses.
If you’re less likely to upgrade your devices with the newest releases, you may have your e-reader longer than the average 2.5 year lifespan.
While paper books win on sustainability for the average American, time and quantity count. If it is likely you will have your e-reader device around for more than a few years, and you read more than the average American, then you can feel good about reading e-books. Bookworms, rejoice!
Considering different user types and consumption scenarios is crucial in determining not only a product’s impact, but its potential design attributes. While electronics often have a greater footprint than simpler objects, the balance can we switched by giving devices multiple functions and targeting the users who will make the most of them.