1. Comparisons of Paper-book and E-book
by the scale of carbon footprint
Hirokazu Shimizu,1 Katsuya Nagata2 and Aran Hansuebsai3
1
Waseda University Environmental Research Institute, Japan
2
Waseda University Graduate School of Environment and Energy Engineering, Japan
3
Faculty of Science, Chulalongkorn University, Bangkok, Thailand
ABSTRACT
E-book is currently trying to take place of Paper-book in western book market because of its
competitive price and easy transfer. Additionally, from the viewpoint of environmental load,
many environmentalists believe that shifting to E-book would assist establishing low-carbon
reading style for readers. When environmental assessment is conducted to compare Paper-book
to E-book by utilizing Life Cycle Assessment (LCA) approach, the fact comes out that
commonly accepted stereotype should be reconsidered in some way. Paper-book is somehow
portrayed as the villain in terms of environmental load, but is not all the time when different
scenarios for usage patterns for devices are set out.
1. STUDY MOTIVATION
The emergence of E-book is remarkable phenomenon especially in US market and it is expected
to influence Asian market sooner or later. Many of printers all over the world worry about rapid
shift from Paper-book to E-book in the near future when comparing those by the scale of price,
storage space, movability and so forth.
A whole lot of academic people making research about environment related matters believe
that E-book has competitive edge in terms of environmental load since no paper and other
materials are consumed. On the other hand, some pinpoint that the loads from producing E-book
reading device and server system for archiving tremendous amount of data are not negligible in
some sense. It was sentient of the fact that assertions from both sides are partly true, so should
be verified by LCA approach to be compared by factual numerical numbers.
Quantification for printing service is already established by past studies, so is utilized to
evaluate environmental impact of real Paper-book production. In fact, comparison should be
conducted by Integrated LCA method focusing not only on CO2e emission but also on other
impact categories such as natural resource consumption, energy drain, water pollution, but only
CO2e emission is selected here for many readers to understand briefly.
2. ANALYSIS
2.1 System boundary of the study
Environmental loads of both Paper-book and E-book productions are quantified by 5-stage (Raw
material acquisition, Production, Distribution, Use and Disposal & Recycle).
Before CO2e emission is calculated, system boundary is configured and shown in Figure 1.

2. Figure 1. System boundary of Paper-book and E-book
2.2 Carbon calculation of Paper-book
The specification of Paper-book is a bit modified from the real one since it was not published yet
as of this moment, but is faithfully cited at maximum as a case study for comparison use.
Calculation consists of Material, Data creation, Printing & Book binding, Distribution and
Disposal/Recycle based on 5-stage of system boundary shown in Figure 1. The stage for “Use”
is not considered for Paper-book since no additional electricity is used for reading except for
lighting and air-conditioning.
The load from “Material” is major one because around two thirds of total load comes from it.
Among materials, paper has significant impact since it occupies almost 60% as a whole.
Whereas, ink and printing plate has no mighty impact though those items are representatives of
printing itself. Other items, which are additive for dampening solution, glues for perfect binding,
polypropylene for cover lamination, have too small impacts to change calculation result.
“Data creation” is precisely investigated this time because it is usually difficult for a printer to
trace back in detail. Every single load from a meeting for brainstorming at publisher, all
writing/designing/editing/image-editing works and photographing including transportation is
checked over at great length.
“Printing & Bookbinding” can be quantified without difficulty because all production
facilities are visible, but “Distribution” is cannot because it is invisible for a printer. So on that
point, it is necessary to set up the scenario here; it is assumed that 6-subscription agent,
including one agent handling mail order, are selected to distribute books all over Japan. It is
summarized as diagram in Figure 2.
Figure 2. Fictional scenario for distributing 5000 books

3. “Disposal/Recycle” is partly quantified based on scenarios; one is disposal ratio vs. recycle
ratio of books after consumers purchase (22% vs. 78%) and the other is returned ratio of the
books (40% returned to publisher’s warehouse on the way of outbound route) after selling those
for several month at bookstores.
Carbon calculation for Paper-book covering all items is summarized in Table 1.
Table 1. CO2e calculation for Paper-book

4. 2.3 Carbon calculation of E-book
A book in this case study is not fully digitalized for E-book in practical, so is assumed to be the
one for comparison purpose here.
There are several kinds of devices, which can be used as E-book readers, but only “iPad”
created by Apple is selected here because of its popularity all over the world.
Carbon calculation per E-book is achieved in Table 2.
Table 2. CO2e calculation for E-book
“Data creation” is exactly the same as the process of Paper-book, so the figure is divided by
3000 downloads which is the same as the number of sold for Paper-book.
“Data management” is the process for data modification to adjust existing data for E-book
format and data verification to check newly adjusted data.
“ICT hosting service” is referenced from carbon footprint certified service by Nihon Unysis.
It is supposed that data size for E-book is 1MB and storage for server system is 50GB, so the
load for E-Book is extremely small and ignorable based on data size of E-book and storage size
shown above.
“iPad” is selected as a device to read E-book even though there are different kinds of devices
right now. The main reason is that Apple published Environmental Report of main products on
their web site, such as MacBook/iPad/iPhone, to disclose detailed data of CO2e emission
throughout life cycles whereas no competitors put before the public.
As a result, CO2e emission per E-book is calculated to compare it to Paper-book. Paper-book
(579g-CO2e/book) is around much more than E-book (277g-CO2e/book) when iPad is used 2-
hour every day all year long. The reason why the time to use iPad is defined as 2-hour a day is
that Apple simply publicizes “intensive daily use of product” to explain usage hours. So, it is
assumed that 2-hour use a day can fit to heavy use and set as basic scenario.
And then, question arises if all users of iPad are using it for full of 2-hour every single day or
not when utilizing it secondarily to assist main computer. It will be variation factor for
sensitivity analysis in the next section.
2.4 Sensitivity Analysis
It is quite difficult to average iPad usage hours per day, so different scenarios are set out for
sensitivity analysis purpose.
As mentioned above, it is uncertain that how many hours of iPad use is set as precondition by
Apple, so division process for total CO2e emission of iPad without considering prerequisite of
usage hours might be inadequacy. However, there is no mean for detail checking, therefore
CO2e emission of iPad is calculated for different scenarios drawn from basic scenario.
For basic scenario, 2-hour use per day for iPad is set, and then 1.0-hour/0.75hour (45-
minute)/0.50 (30-minute) usage hours per day are configured for sensitivity analysis. The loads
to use iPad from different scenarios are calculated and other loads are added to draw the result
for reading E-books to be compared. The loads from E-book device for different scenarios are
calculated based on Apple’s environmental report and final calculation for E-book is
summarized in Table 3 and in Figure 3 respectively.

5. Table 3. CO2e calculation for E-book device
Figure 3. Sensitivity analysis based on iPad usage hours per day
As explained in previous section, E-book is superior to Paper-book by basic scenario, but it is
not by Scenario-2 and Scenario-3, namely it is inferior to Paper-book when using iPad for 45-
mimnute a day or less.
When iPad is used for 30-minute a day, it could be common for many users, CO2e emission of
E-book is more than triple of Paper-book. On the other hand, when iPad is used for 2.0-hour a
day, it might be exactly the case for quite a few users; CO2e emission of E-book is less than half
of Paper-book. Calculation range goes beyond much more than imaginings by different
scenarios; a scenario for E-book device usage can determine environmental impact of E-book.
3. CONCLUSION AND DISCUSSION
By utilizing simplified LCA method, the fact that E-book always performs better than Paper-
book can throw doubt on commonly accepted myth among environmentalists.
It is obvious that key element to determine the load for E-book comes from the load of device;
averaged hours of device usage should be investigated precisely to solidify the result for
comparisons in terms of environmental load. It might not be so important to work on detailed

6. studies of “Data management” to convert printing data to E-book and “Server operation” to store
data since serious commitment to scrutinize the loads could not influence the result.
What should be done for comparison of Paper-book and E-book is that figuring out how to
average usage hours of E-book devices to read books by extensive survey.
ACKNOWLEDGEMENTS
I wish to express my sincere gratitude to my academic supervisor, Professor Katsuya Nagata at
Waseda University Graduate School of Environment and Energy Engineering for helpful
suggestions and valuable advices during my research.
I also would like to thank Associate Professor Dr. Aran Hansuebsai at Chulalongkorn
University for inspiring my research for years.
REFERENCES
Hirokazu Shimizu. 2009. Establishment of quantitative assessment for Printing Service. Journal of
Printing Science and Technology 46 (6): 26-35
Hirokazu Shimizu, and Katsuya Nagata. 2010. Comparison of Life-cycle CO2 emissions for Paper-Based
Books and Electronic Books. Journal of Printing Science and Technology 47 (2): 19-29
Hirokazu Shimizu, and Katsuya Nagata. 2010. Integrated Life cycle Assessment (LCA) Approach for
Printing Service by Using Environmental Load Point (ELP) Method. Journal of Printing Science
and Technology 47 (3): 39-47
Hirokazu Shimizu, and Katsuya Nagata, and Aran Hansuebsai. 2011. Integrated Life cycle Assessment
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Nihon Unisys. 2012. ICT hosting service. Available online, http://www.unisys.co.jp/services/ict/cloud-
computing2.html#gict_h2-20. Accessed: August 14, 2012
Apple Inc. 2012. iPad Environmental report. Apple and the environment. Available online,
http://images.apple.com/environment/reports/docs/iPad_Product_Environmental_Report_March20
12.pdf. Accessed: August 14, 2012
Address: Hirokazu Shimizu, Waseda University Environmental Research Institute
E-mail: hstav@asagi.waseda.jp