The research and media company drew on existing studies to do a lifecycle analysis and found that the carbon emissions from electronic books are far lower than traditional book publishing.
Taking into account the manufacturing and mining required to produce an electronic device still gives the Amazon Kindle a significant edge, according to the study by Emma Rich.
"The roughly 168kg of CO2 produced throughout the Kindle's lifecycle is a clear winner against the potential savings: 1,074kg of CO2 if replacing three books a month for four years; and up to 26,098kg of CO2 when used to the fullest capacity of the Kindle DX. Less-frequent readers attracted by decreasing prices still can break even at 22.5 books over the life of the device," she wrote in conclusion.
Ebook readers aren't typically marketed as environmentally sound, but their environmental impact is now becoming a topic of discussion and research.
In a test, six universities in the US will make textbooks available on the Kindle DX specifically to use less paper. "Sustainability is the driving force behind Princeton using the Kindle," a representative told the New York Times in May.
Still, there are some obvious environmental drawbacks to using electronic devices -- the Kindle's 168kg of carbon dioxide from its manufacture, shipping and electricity to run compares to just 7.46kg for a book, the Cleantech Group says, citing various sources.
Electronic waste, too, is a growing problem many tech gadget owners have yet to fully address. On this point, Amazon has said it will establish a recycling programme for the Kindle and its battery by mail to reduce electronic waste.
The Cleantech Group argues that the electronic reader industry can make a significant impact once people start transitioning from paper media en masse: "A user that purchasers fewer than 22.5 books per year would take longer to neutralise the emissions resulting from the e-reader, and even longer to help reduce emissions attributed to the publishing industry," according to the study.
Intuitively, the basic conclusion of the Cleantech Group analysis makes sense: the more you reduce your use of paper media in a single electronic device, the less you'll pollute by harvesting and shipping physical goods. But as with many proposed 'fixes' to environmental problems, there are trade-offs.
Ultimately, it comes down to how an ebook reader is used. If a person continues to buy books and print periodicals and doesn't recycle the product, the environmental impact could potentially be negative, according to this study.