Commercial electronic books (or e-books) were first introduced around the late 1990s, and as their popularity grew steadily over the years, it was easy to assume that printed books would become a thing of the past. However, despite the rise of the internet and society’s shift to digital lifestyles, there’s still no replacing the look, smell, and feel of a physical book.

According to the Association of American Publishers, paperback sales country-wide increased by 2.7 percent from 2018 to 2019, while e-books declined by about 4.2 percent. That said, there’s no denying that being able to store hundreds of books on a single device is exceedingly convenient. However, it doesn’t necessarily mean that e-books on a dedicated reading device are more eco-friendly than owning stacks of classic paper books. If you’re deciding whether or not you should make the switch, here are some factors to consider.

Paper production may contribute to deforestation

The primary component of books is paper, which means chopping down trees for your favorite works of literature.

“Paper production encompasses harvesting trees, pulpwood and pulp production, bleaching, sheet forming, drying, and cutting,” says Gregory A. Keoleian, the director of the Center for Sustainable Systems at the University of Michigan. “Papermaking is a water resource-intensive process and a variety of chemicals are used in the pulping and bleaching process, resulting in air and water pollutant emissions.” 

Moreover, trees store carbon and help mitigate climate change. By cutting them down, we release more carbon dioxide into the atmosphere. The global loss of tropical forests contributes about 4.8 billion tons of carbon dioxide per year, which plays a major role in global warming. However, it’s important to note that many paper companies harvest wood sustainably from commercial tree or pulpwood plantations, not from natural forests.

[Related: Where does your paper come from? The good and the bad news.]

“A key factor in reducing the environmental effects of book production is to source trees that have been grown with responsible forestry practices,” says Jennifer Dunn, co-director of the Center for Engineering Sustainability and Resilience at the Northwestern McCormick School of Engineering. “There are a number of certification schemes that strive to encourage responsible, sustainable forestry.”

Nearly all members of the American Forest and Paper Association get their wood fiber from sustainable sources. In addition, about 95.4 million acres of forests in the country have been certified with at least one forest certification system, which means that forest products originate from land that is sustainably managed.

Aside from paper, books also require raw materials like petroleum to produce printing ink. Fossil fuels are also needed to transport books from distributors to stores and finally to readers’ hands all over the world.

Manufacturing e-readers requires plenty of natural resources

An electronic device like an e-reader requires the extraction of valuable metals and minerals from the earth, such as copper, lithium, and cobalt. Manufacturing one e-reader needs about 33 pounds of minerals.

Mineral extraction and refining operations for the manufacturing of electronic devices have a wide range of environmental impacts, from mining wastes and water contamination to air pollution from smelting, says Keoleian.

Like any consumer electronic, e-readers are generally energy- and water-intensive. It’s difficult to nail down the exact amount of energy consumed in producing an e-reader from all its component parts, and the international supply chain only complicates the process further, says Dunn. It is estimated that producing one e-reader uses around 100 kilowatt hours of fossil fuels and 79 gallons of water, and also emits 66 pounds of carbon dioxide.

[Related: Does reading an e-book make us happier than playing a video game? The answer is complicated.]

Even after an e-reader is produced, the device requires energy since it has to be charged over and over again. On the assumption that an e-reader will last a decade, it can use up about 194 megajoules of energy in its lifetime. For context, a petrol car uses about 142 megajoules per 100 kilometers.

Additionally, storing and downloading data from the internet has a carbon footprint. According to the International Energy Agency, global data center electricity use made up around 1 percent of the global final electricity demand in 2020, and data transmission networks composed about 1.1 to 1.4 percent of global electricity use.

“The electricity consumed for data storage of information is growing at an exponential rate, and data for e-books is part of this trend,” says Keoleian. “We all need to be aware that transferring each kilobyte of data and information via the internet has an environmental impact, particularly from electricity consumption from servers and routers in the network.”  

The eco-friendlier option depends on how often you read

Manufacturing both paperbacks and e-readers requires a lot of energy and natural resources. When comparing their environmental impact, the number of books someone plans on reading is a crucial factor

“On a mass basis, comparing the production of a one kilogram of paper with one kilogram of electronics equipment, the e-reader would have a much greater impact,” says Keoleian. “But the utility of the e-reader for downloading and reading multiple books is where there is the advantage, even when considering the energy requirements during use and storage of data on servers.”

Mike Berners-Lee, a professor of practice in Lancaster University’s Environment Centre, wrote in a post for New Scientist that a reader must go through at least 36 books (paperbacks that could be recycled) before evening out for an e-reader’s footprint. Pierre-Olivier Roy, a lead energy and senior consultant at the International Reference Centre for the Life Cycle of Products, Processes, and Services (CIRAIG), a Montreal-based sustainability research group, also found that heavy readers may want to switch over to the digital side, especially if they are powering through dozens of textbooks each year. One 2017 study shows that even replacing around five 360-page hardback books each year with an e-reader could lower global warming potential. This rounds out to about nine smaller books each year, according to CIRAIG.

But this research has been going on for over a decade. A 2009 analysis from research and consulting group Clean Tech Group found that even replacing 22.5 paper books each year could break even the impacts of a Kindle. According to one 2012 analysis from the Rochester Institute of Technology, if you read about 60 books per year, the e-reader may be the “eco-friendly” option. Another analysis from 2010 in the New York Times shows that with everything into account—including fossil fuels, water use, mineral consumption, and impact on global warming—an individual would have to read about 100 books to break even with the environmental impact of one e-reader.

[Related: Your e-reader can display more than just books.]

No matter which book format you prefer, it’s crucial that you dispose of either reading device properly. Books accounted for 0.2 percent of total municipal solid waste generation in 2018 with 690,000 tons, while consumer electronic goods represented less than 1 percent at 2.7 million tons

“Another environmental challenge for e-readers is that it is difficult to recycle them at the end of life, so we generally lose the metals and other high-value components they contain,” says Dunn.

Overall, if you’re a frequent reader, an e-reader like Kobo or Nook may be the best option. That said, experts say you can still reduce your literary carbon footprint by lending or donating paperbacks, buying secondhand books or e-readers instead of new ones, and borrowing books or e-readers from your local library.