Compared with a conventional textbook it’s obvious that an e-text saves energy and reduces greenhouse gas emissions—or is it?
When you actually look at the way students use both kinds of textbooks the obvious turns out to be not so obvious. Looking at the behavior of college students is exactly what Thomas F. Gattiker, Scott E. Lowe, and Regis Terpend did in order to determine the relative energy efficiency of electronic and conventional hard copy textbooks.
They used survey data from 200 students combined with life cycle analysis of digital and conventional textbooks and found that on the average the carbon footprint for digital textbooks is a bit smaller but not as much smaller as you would hope.
In a short summary article for The Chronicle of Higher Education, Gattiker and Lowe write:
“We discovered that when we consider all greenhouse-gas emissions over the life cycle of the textbook, from raw-material production to disposal or reuse, the differences between the two types of textbooks are actually quite small. Measured in pounds of carbon-dioxide equivalent (CO2e), a common unit used to measure greenhouse-gas emissions, the use of a traditional textbook resulted in approximately 9.0 pounds of CO2e per student per course, versus 7.8 pounds of CO2e for an e-textbook.”
However, there is a wide variability in the energy used by individual students, and the reasons are easy to understand. Some of the factors that matter are:
- the device on which the e-text is read (desktop computer, laptop, dedicated e-reader)
- the number of pages printed by the student and whether the pages were two-sided or single-sided
- the source for the electric power (hydro, coal, natural gas)
- the number of times a hard-copy book is resold
Compare a 500-page conventional text with the same text in digital format. If the student reads it on a desktop computer located where electric power is generated by burning coal and if the student prints 200 one-sided pages, then the carbon footprint is much greater for the e-book. But if the student reads it on an e-reader, doesn’t print much, and gets hydro-electric power, then the e-book has a much smaller carbon footprint.
They identify three “levers” that college faculty and students can use to reduce the carbon load associated to textbooks:
- Encourage multiple use of hard-copy textbooks.
- Read e-texts on laptops and dedicated readers rather than desktop computers.
- Print on both sides with recycled paper.
The full article describing the research of Gattiker, Lowe, and Termpend is “Online Texts and Conventional Texts: Estimating, Comparing, and Reducing the Greenhouse Gas Footprint of two Tools of the Trade,” Decision Sciences Journal of Innovative Education, Volume 10, Issue 4, pages 589-613, October 2012.