Life Cycle Analysis:
E-reader and Printed Books
Peter Ding, Simon Evans, Chong Hong,
Yu-Cheng Lin, Alex Norring
Environment 159
Professor Deepak Rajagopal
1 Table of Contents
Abstract ........................................................................................................................................... 3
Goal and Scope ............................................................................................................................... 3
Literature Overview ........................................................................................................................ 4
Functional Unit, System Boundary, System Flow Diagram and Method....................................... 7
Lifecycle Inventory Analysis .......................................................................................................... 9
Books........................................................................................................................................... 9
E-reader ..................................................................................................................................... 10
Lifecycle Impact Analysis ............................................................................................................ 13
Sensitivity and Uncertainty Analysis ............................................................................................ 19
Monte Carlo Uncertainty Assessment ....................................................................................... 19
Book: Number of Books ........................................................................................................ 19
E-reader: Cost of Glass & Distance Traveled ....................................................................... 20
Sensitivity Analysis ................................................................................................................... 20
Limitations of Current Work ........................................................................................................ 21
Conclusions and Recommendations for further studies................................................................ 22
References ..................................................................................................................................... 24
Appendix ....................................................................................................................................... 26
Appendix A: Flow Charts ......................................................................................................... 26
Appendix B: Life Cycle Inventory Analysis ............................................................................. 27
Appendix C: E-book Materials Cost Inventory......................................................................... 28
Appendix D: Life Cycle Impact Analysis Graphs .................................................................... 28
Appendix E: Sensitivity Analysis ............................................................................................. 31
Appendix F: Uncertainty Analysis ............................................................................................ 34
2 Abstract Recently, the long running print version of the Encyclopedia Britannica was ended in favor
of online and electronic publishing and access. So this raises the question, in terms of their life
cycle impacts, which version of a book is better: printed or electronic. In this Life Cycle Analysis
(LCA), we examine the impacts associated with Energy Use and Global Warming Potentials
(GWP) for the manufacture of one E-reader and its manufacturing equivalent of 1100 printed
book capacity. We conducted our LCA through analysis of data obtained through different tools
such as scholarly articles, average industry specifications, and the Economic Input Output LCA
(EIO-LCA) tool. We made a number of assumptions in the course of our LCA. For these
parameters, however, we found that for both energy use inputs and GWP outputs, the E-reader
was better for the environment. In the study, we further broke down the impact assessment into
different categories to determine where the most significant impact was located (manufacturing,
transportation, use, and disposal). We conducted several sensitivity analyses and Monte Carlo
uncertainty analyses to determine what happens when we change certain variables that we had
made assumptions for and how this affects our overall outcome and impacts. In the end we
determined that if using the E-reader to full capacity, E-reader is a better option for the
environment.
Goal and Scope The E-reader is a new emerging technology that allows users to store and read many books
on one small device. This replaces the need for the production of traditional paper books, whose
production consumes many natural resources. While at first glance this comparison may look
simple, the E-reader consumes energy during its use, and its production requires many more
3 parts than the paper book. The goal of this life cycle analysis is to compare the production of an
E-reader with the production of paper books to see which product is more environmentally
sustainable. The comparison will be for generic industry data for both technologies and a
sensitivity analysis will be conducted on the makeup of the energy sources used for
manufacturing. Environmental sustainability will be determined by comparing the global
warming potential and energy input per functional unit. The functional unit is used to compare
the two different technologies, and is defined as 1,100 books per one E-reader. The life cycle
analysis will consist of stage two analyses for both e reader use and paper book use. The system
boundaries are defined in the flow charts presented below, and include recycling and disposal of
product, use of product, distribution, production, and component production.
Literature Overview “Printed Scholarly Books and E-reader Reading Devices: A Comparative Life Cycle
Assessment of Two Book Options” is an analytical report comparing books and E-readers using
life cycle assessment by Greg Kozak. It is a very comprehensive report comparing books and Ereaders in various LCA perspectives. The methodology computes the values of different
components within books and E-readers ranging from production, manufacturing, distribution,
use and end of life management. For each life cycle unit process, inputs include product
materials, ancillary material and energy resources, and outputs include primary product, air
emission, water effluent and releases to land. The report also provides full explanations
regarding data collection, computation and analysis for every single small factor within book and
E-readers. After completing LCA, the sensitivity analysis is also completed for both subjects in
detail. There are a total of 16 sensitivity analyses, and one variable was changed for each
4 sensitivity analysis. However, the report only analyzes scholarly books, which are much heavier
than normal-weighted books. There was no comparison done between scholarly and normalweighted books completed in the report.
Two papers we made use of are from Asa Moberg, Clara Borggren, and Goran Finnveden
titled “Books from an environmental perspective – Part 1: environmental impacts of paper books
sold in traditional and internet book shops” and “Books from an environmental perspective –
Part 2: e-books as an alternative to paper books”. These two sequential papers detail life cycle
assessments of two sectors of paper books which were useful to our analysis. In Part 1, they
examine how impacts for printed books have changed with the advent of electronic purchasing
ability. These impacts change based on whether being shipped to the customer or having the
customer drive directly to the store to purchase the book. During this study, they examined the
impacts of manufacturing of a paper book, however, the limitations of this study for application
to our own was that it was conducted in Sweden. Sweden has a slightly different mix and range
of energy and emissions. In part 2, they discuss impacts of an e-book instead of actually reading
the paper book. This is much like the Kozak article referenced earlier, doing a life cycle analysis
of e-reader to printed book. They found overall that there was no exact way to determine which
system was better in terms of impacts, but they did give a number of ways in which the e-reader
could improve to make it more competitive with books in environmental impacts. Both these
utilized databases in their study to determine impacts, but if no data was available in such a way,
they used industry averages.
Another paper we utilized for our overview of book production is “Environmental
Implications of Wireless Technologies: News Delivery and Business Meetings”. Authors
5 Michael Toffel and Arpad Horvath analyzed newspaper production and paper production.
Although they looked mainly at newspaper everyday delivery and the impacts it has on the
environment when comparing electronic delivery against paper delivery, there was some book
analysis and the amount of energy required in distribution.
For the E-reader analysis, we used the top ten reviews website to get the average mass and
screen dimensions of ten E-readers. In addition, we used G. Kozak’s review to get the
compositional weight breakdown of the E-readers. For the mass of raw materials not available in
G. Kozak’s review, we used several different websites and literature. For Lithium, we used the
calculation from Fedex Express, after learning about how a battery works from
batteryeducation.com. After obtaining all of the compositional data for our study, we consulted
literature such as [Koch, Keoleian et al. 1995] and [Caudill 2000] to compare our findings with
findings which have already been done.
The case study: “Building a Model to Calculate Energy and CO2 Emissions”, by S. Cholette
was used to develop the data for e-reader transportation from the Chinese factory to the
distribution centers in the United States. This case study utilized the same route for transport,
albeit for a Nintendo Wii. Since the Nintendo Wii and an e-reader are of similar size, the data
was assumed to be applicable to our life cycle analysis. The case study used the model Cargo
Scope to calculate the energy and emissions data. This model uses nodes and links to create a
distribution network, and subsequently models the emissions.
“Wood in our future: The role of life-cycle analysis: Proceedings of a symposium” by Board
of Agriculture, National Research Council, conveys that the use, availability and cost of wood,
which has been used for many applications, has come under increasing attention. This is a result
6 of environmentally driven social government policies, and therefore substitutions for wood as a
raw material is necessary. A life cycle analysis is used to assess paper production from tree to
product, and also assess the environmental impacts to prove that the continued use of wood
products as an input is environmentally unsustainable.
Functional Unit, System Boundary, System Flow Diagram and Method In our analysis, we will be comparing the amount of energy and greenhouse gas emissions
produced in producing an E-reader and an equivalent amount of books. In light of this, we will
be making the assumption for the functional unit that an average E-reader has the capacity to
hold up to 1,100 books, based on the numbers we researched from E-readers such as the Sony Ereader, Amazon Kindle, and the Nook. Of our unit processes, paper recycling for the most part is
not recycled back into the system. Based on our research we found very little book printers using
recycled paper to make pages, therefore we chose to count this impact as negligible. Since none
of our unit processes in the E-reader flow diagram yield multiple products; we assume that all the
processes are specialized in production.
Although the average E-reader holds 1,100 books at a given time, the device may not
hold a total amount of 1,100 books throughout its lifetime. Therefore, we will use 1,100 as a
starting point and conduct a sensitivity analysis by scaling it to different values to account for the
variability. Also, a e-reader may also read more than just books – it can also read newspapers,
journals, and magazines.
For books and E-readers, we are using a hybrid LCA where the main process (transport,
packaging, e-reader use, manufacturing, and disposal) are all accounted for by the process LCA,
whereas the auxiliary inputs to some of these unit processes are accounted for by the EIOLCA.
7 For example, most of the data for the raw materials (such as PVC, copper, and aluminum) were
extracted from the EIO LCA tool. Outside of EXCEL, EIO LCA, and models from literature,
we’re not using any other software or products for our analysis.
The usage data was computed by using an industry average for charging time and wattage
of the charger for an e-reader. This led to each full charge of four and a half hours using
.450KW. Since each full charge lasts approximately one month before needing to be recharged,
in a single year an e-reader will use 19.4MJ. Based on the assumption that an E-reader will be
used for a decade, one e-reader will use 194 MJ of energy over its lifetime.
The E-reader transportation data consisted of three distinct steps. First the E-reader was
trucked to the Port of Shenzhen from the factory warehouse in Shenzhen. The E-reader was
assumed to have been produced at the Longhua Science and Technology Park, and manufactured
by Foxconn. This factory complex is one of the largest in the world, and produces multiple
leading brands of e-readers (Dean, 2007). The second step was shipping of the E-reader from the
Port of Shenzhen to the Port of Long Beach. The third step was national distribution in the
United States. The global warming potential and energy input from these three steps was
modeled after the Cargo Scope model as used by S. Cholette.
The disposal of the E-reader was assumed to be negligible for the life cycle analysis. This
was decided because E-readers are not recycled due to high costs for minimal returns. Therefore
consumers would dispose of e-readers through conventional methods such as ordinary trash
collection. Due to the long life and small size and weight, it was assumed the E-reader’s global
warming potential and energy usage for disposal would be negligible.
8 Lifecycle Inventory Analysis Books Since there are light-weighted books and heavy-weight books in our analysis, there are
separate assumptions only for the specific type of book. For light-weight books, one book
contains 634 pages, and the average weight per book is 0.518kg. For heavy-weight books, one
book contains 500 pages, and the average weight per book is 1.052kg. There are many common
assumptions for both light-weight and heavy-weight books. The paper recycling rate is 20% of
the total book use, and the remaining 80% will go to disposal. The manufacturing rate is
approximately three times that of book distribution. For raw materials, the weight of wood used
is about 2.33 times the actual book production, and the ink used is about 10 times of number of
pages of books. The transportation distance for book distribution is 2000 miles. The average
transportation fuel and energy requirements for a diesel tractor-trailer were found to be 9.4
gal/1,000 ton-mile and 1,465 Btu/ton-mile, respectively.
A lot of the data extracted for the book inventory analysis is from G. Kozak’s report, and
some data is from EIOLCA tool. The energy input and green house gas emissions for disposal
and paper recycling of books were assumed to be negligible for the life cycle analysis. This was
decided because disposal and paper recycling do not consume a lot of energy, instead, most of
them just directly dump to a landfill.
9 Table 1. Life Cycle Inventory Analysis for Printed Books (1100 books)
Unit Processes
Sub-Unit
Process
Book Use
Reading/Storage
Recycling
Paper Recycling
Disposal
Circulation
Distribution
Manufacturing
Manufacturing
Wood
Ink (microliters)
Energy
Other Materials
Distribution
Fuel(gal)
Packaging
Materials
Cardboard
Plastic
Total
Weight
(kg)
864
173
691
864
2591
2012
5670
0
0
22
6
Energy Input
[MJ]
0
0
831.6
2944
36019
2394
0
33625
0
2944
240
Greenhouse gases [kg]
2
4
96.4
143.6
39795
0.136
0.029
5433
0
0
61.16
571
4800
3024
0
1440
0
571
0.165
E-­‐reader We assumed that the total mass for our E-reader is the average of the 10 E-readers found
from the literature, which is 338.38 grams (toptenreviews.com). Furthermore, we assumed that
the five major components of an E-reader are cable, battery, chassis, LCD screen, and the
adapter components (electronics). In order to obtain the compositional percentages and mass of
these parts, we consulted Greg Kozak’s LCA literature [Kozak. 2003], which highlighted a
typical percent breakdown of an E-reader.
Furthermore, we assumed for simplicity’s sake that for each of these processes, there
existed only two major inputs per process. For example for cable production, the two inputs were
simply PVC and Copper. Next we looked to evaluate the impact categories for these inputs. The
tool that we used for this part is the EIOLCA tool developed by Carnegie Melon. In order to
10 obtain the total economic activity input needed by the tool, we aimed to find the price of the raw
material (e.g. copper, PVC) and the total mass of the raw material. For metals such as copper,
aluminum, lithium, and zinc the weights were found at [metalprices.com] which highlighted the
average price per pound of some common metals. For the price per unit weight of less common
entities such as PVC, literary sources were consulted. The price per unit weight of PVC was
determined from literary sources [Ackerman. 2003].
To use the EIOLCA of each raw material, first of all, we selected Industry Benchmark
US Dept of Commerce EIO model from 1997. The activity economic is required, and further
information is needed. In 2011-2012, the average price of iron was $140 per ton, $8060 per ton
for copper, $2000 per ton for zinc and PVC per pound is $1.15. Using both LCI data and the
market price of sub-materials, we could calculate the numbers of each raw material’s economic
activity. For instance, to account for the economic activity of iron, the iron mass is 143.22g of
each E-reader and the market value is $140/ton. A complete inventory of the materials pricing
can be found in the appendix.
It means that to produce an E-reader required $0.02 iron. Following with the same
process, copper costs $0.117, zinc costs $0.0217, and PVC costs $0.1464. Meanwhile, LCD
display glass costs $154 per kg. The amount of price is based on the assumption that the LCD
10.1 of Samsung tablet weights 130g and that the marketing price is from $20 to $40 of each
panel. After briefly calculating, we can assume the price is $20 per panel divided by 0.13kg per
panel; the result is $154/kg. The mass of LCD glass on LCI model is 0.0429kg, so the required
cost of each LCD panel is $6.51. LCI data of components of the E-reader is based on the major
parts; however it should be noted that this E-reader mass excludes the USB cable, telephone
cable, CD-ROM, screen electronics, and all packaging elements.
11 To run the model of EIOLCA and to calculate GWP emissions, we have to make
assumption that the unit of economic activity is one million dollars instead of one dollar. It is
because that the input data will be too small to get any valuable result if one dollar was used. For
example, to evaluate how much carbon dioxide would be produced by lifecycle of manufacturing
of iron, we selected iron and steel mills, input $0.02 million dollars as unit amount of economic
activity of producing iron process, and chose GHG emissions. After running the model, the table
showing global warming potential is derived. GWP emission data could be viewed on the table,
which amounted to a total of 54.9 mega tons. However, the goal of this LCI analysis is to
identify how much of GWP gases are discharged while producing one E-reader. This amount of
GWP was calculated to equal 54.9g GWP. We can use the same method to evaluate other
material’s GWP emissions. For copper, we selected secondary processing of copper, inputted
$0.117 million dollars and ran the model. The GWP emissions result in a total of all sectors of
70.9 megatons. Therefore each E-reader could produce 70.9g GWP due to manufacturing and
refining raw materials. By the same analysis, the emissions of GWP from zinc is 32.6g, from
PVC is 243g, and glass is 3176g.
In addition, we evaluated the total energy consumption of an E-reader by the EIOLCA
model. The analysis was changed from the global warming potential to energy consumption.
While the LCI data remains the same in both cases. For example, the LCD glass is a large source
of energy consumption. The industry specific option for LCD glass does not exist, so the sector,
“All other electronic component manufacturing” was used instead. The economic activity for the
LCD screen was found to be $6.51 per panel on the E-reader. To avoid rounding errors, we input
$6.51 million per million panels. The result shows 36.7TJ of energy is required to produce a
million LCD panels for E-readers. This analysis reduces to 36.7 MJ/ one panel. Using the same
12 method, the values of energy input for iron, copper zinc and PVC can be evaluated. 0.601MJ was
found to be the energy needed to produce the iron component for one e-reader, 0.812MJ for
copper, 0.431MJ for zinc and 1.53MJ for PVC.
Table 2. Life Cycle Inventory Analysis for E-reader
Unit Processes
Sub-unit Processes
Total Weight (g)
E-Reader Use
Transportation
Packaging
Power Generation &
Supply
manufacturing
product travel
Cardboard
Cable
Battery
Adaptor
Chassis
LCD Screen
Power Generation &
Supply
PVC
Copper
Aluminum
Lithium
Iron
Copper
Zinc
PVC
Glass
Transportation
Packaging
Manufacturing
Cable
Production
Battery
Production
Electronic
Production
Chassis
Production
Screen
Production
Total
GWP CO2e [g]
402.7
-
Energy Input
[MJ]
32.25
17.86
6737
338.38
338.38
402.7
30.12
31.75
166.53
67.68
42.3
-
101.591088
32.25
17.86
3.207
4.37
1.413
1.961
36.740088
53.9
6098.1012
2.354
0.748
190.8
660
125.8
275.6
3165.9012
1680
15.66
14.46
31.31
0.459
143.22
23.31
10.83
56.84
42.3
0.587
2.62
3.86
0.51
0.601
0.812
0.431
1.53
36.740088
35.8
155
264
396
54.9
70.9
32.6
243
3165.9012
741
6889.2
2690.8 (kg)
2354.5
0.748
2682333.5
Lifecycle Impact Analysis In looking at our two life cycle inventory analysis tables for the E-reader and printed books,
we can calculate a total life time impact assessment for each. In total, we calculated that for an E13 reader, energy inputs were equal to 6889.204 MJ. We calculated the total life time impact of
Global Warming Potentials for an E-reader to be 2690.79 kg of CO2 equivalents. Similarly, we
took all sectors for the printed books and determined total lifetime energy inputs to be 39795.02
MJ and total global warming potentials to be 5432.51 kg of CO2 equivalents. We created a graph
comparing these two total life cycle impacts, which can be seen in Figure 1.
Life Cycle Impact Analysis 45000 40000 35000 30000 25000 20000 15000 10000 5000 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 6889.204842 2690.786815 Book 39795.0244 5432.509003 Figure 1. Total Life Cycle Impact Assessment
After analyzing this total life cycle case, it is apparent that an E-reader outperforms the
equivalent number of books in both categories of analysis. For energy inputs, the total life of an
E-reader uses only 17% of the energy required for 1100 printed books. For CO2 equivalents, we
found that for the life of an E-reader the GWPs released were 52%, approximately half, which is
a significant difference from the ratio we found for energy inputs. We must remember that 1100
books is a significant number of books to read and thus, will perform a sensitivity analysis to
14 determine how changing the number of books read on an E-reader will change our threshold for
the units of analysis.
When looking at this impact analysis, we conclude that the energy used throughout the
lifetime of an E-reader is a much higher pollutant emitting energy source for GWPs. Thus, we
delved deeper into the life cycle processes of both these methods for book reading to determine
where the greatest impact is in the life time. As can be seen in our flow chart (Appendix A)
showing our stage 0, stage 1, stage 2, and disposal, along with our inventory analysis breaking
down the components into unit and sub-unit processes, we analyzed four main areas of the life
cycles. These four areas were disposal, use, transportation, and manufacturing.
When breaking down the impact assessment into four areas of analysis, we have some
interesting findings that lead to a number of conclusions. In disposal, we took the energy inputs
and GWPs to be negligible for the E-reader because we assumed the small amount of lithium in
the batteries was not worth recycling and therefore the entire unit was just disposed of. However,
when we averaged out the entire load of a garbage truck, we found the amount of energy needed
to transport one E-reader to the landfill to be miniscule and not impactful in our comparison.
With 1100 books though the impact was higher because they weigh more and there is more that
is involved in disposal. The calculations and data can be seen for disposal can be seen in Figure 2
below. These numbers would change if we changed our assumption to books never being thrown
away which would make impacts equivalent to E-reader at 0, or E-reader actually having a
slightly bigger impact.
15 Disposal Impact Analysis 1000 800 600 400 200 0 E-­‐Reader Book Energy Input [MJ] GWP CO2e (kg) 0 0 831.6 61.16 Figure 2. Disposal Impact Analysis
For use impact analysis we determined that the E-reader had a much bigger impact for both
energy inputs and GWPs because it requires energy, thus emissions, in order to operate the Ereader. Books require zero energy to operate, aside from the light above, which we assumed was
the same amount required to read an E-reader, therefore they offset each other. The results for Ereader use and book use impact assessment are shown below in Figure 3.
Use Impact Analysis 8000 6000 4000 2000 0 E-­‐Reader Book Energy Input [MJ] GWP CO2e (kg) 6737.5 2682.3335 0 0 Figure 3. Use Impact Analysis
16 Distribution is a big impact sector. E-reader is manufactured in China and therefore must be
shipped to the United States. Once it reaches the Port of Los Angeles, the E-reader must be
trucked to distribution centers located throughout the country. For this we took the average
distance one E-reader must travel. As can be seen from Figure 4, the actual energy inputs for this
distribution remain relatively low per E-reader unit. However, the GWP released far outranks
that of printed books distribution, despite printed books having a higher energy input impact.
This is in part because E-readers must travel further distances, which include ship transportation.
Distribu8on Impact Analysis 3500 3000 2500 2000 1500 1000 500 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 50.11375413 2355.214213 Book 2943.970282 571.4912725 Figure 4. Distribution Impact Analysis
Manufacturing would seem to be the life cycle sector where there would be the most impact.
We can see this to be true. Looking at Figure 5, we see the manufacturing impact comparisons.
For the manufacturing of 1100 books, we see that there is a huge impact on energy inputs. This is
actually the most impactful area of a books life cycle, accounting for approximately 90% of life
time required energy. This is the area of a books life cycle that can become more
environmentally friendly and can take advantage of new renewable energy technologies to help
17 improve the life cycle impacts of printed books. Manufacturing of an E-reader is relatively low
on energy inputs, but once again we see that the GWPs, while almost equivalent, are slightly
higher for E-reader manufacturing. As stated earlier, E-readers are manufacturing in China,
which has less stringent regulations on energy sources and their emission outputs. As a result, we
see high GWP outputs for the electronic manufacturing of E-reader.
Manufacturing Impact Analysis 40000 35000 30000 25000 20000 15000 10000 5000 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 101.591088 6098.1012 Book 36019.45412 4799.85773 Figure 5. Manufacturing Impact Analysis
These are not the only two categories by which to compare E-reader and printed books. As
with any life cycle analysis, there are multiple sectors that can be analyzed and broken down.
However, for the purpose of time and available data, we chose energy inputs and GWPs as our
units for impact analysis and comparison. Based on the overall life cycle impact assessment for
the E-reader compared to the printed books, we can see that for both categories, the E-reader
performs better (Figure 1). Again this does not take into account our sensitivity analysis or
uncertainty analysis, which we can change a number of variables to determine where the true
significant impacts lie. The main area in which the E-reader can improve its overall performance
18 is through its usage stage. Considering the large margin of difference between energy usages for
printed books compared to energy usage for an E-reader, the E-reader can become more efficient
and lower energy usage. In addition as the energy sector starts to use renewable energy sources,
the impacts from usage will decrease greatly, almost approaching 0 like a book.
Sensitivity and Uncertainty Analysis Monte Carlo Uncertainty Assessment In addition to the sensitivity analysis, we also performed Monte Carlo analysis to simulate a
case where there were 1,000 different variations of our sensitivity criteria. Again, those three
criteria were number of books, cost of glass ($), and distance traveled in E-reader shipping. To
begin our analysis, we started with some basic assumptions. The first assumption we made was
that all distributions were triangular. In response to a lack of actual sample of data, this
assumption was made arbitrary and based on our best professional judgment. The rest of the
assumptions we made were specific to the sensitivity criteria.
Book: Number of Books As mentioned in the Functional Units section, the base value (capacity) for the e-reader
was 1,100 books, though an E-reader may not necessarily hold just 1,100 books throughout its
lifetime. We assumed that the minimum books held were just 2% of the base (22 books) and the
maximum books held 500% of the base (5,500). Similar to the sensitivity analysis, we assumed
energy and greenhouse gas warming potential to be a linear function of the number of books. For
example, because the total energy measured from our impact assessment is 39,395 MJ (36.177 x
1000), we established our equation to be 36.177 x n, where n was the randomly generated
number of books in the Monte Carlo assessment.
19 E-­‐reader: Cost of Glass & Distance Traveled In contrast to the Monte Carlo assessment for books, we assumed energy and greenhouse gas
warming potential to be combination of the linear function of the cost of glass and distance
traveled. The baseline value for the cost of glass was $6.51 and we assumed the minimum cost to
be 10% of the base and the max to be 110%. The reason we assumed this was because in view of
a relatively high glass price compared to the other raw materials, we wanted to see how a very
low cost for glass will affect the overall environmental impact. As for the distance traveled, the
min and max range was 50% and 150% respectively. The equation for total energy was 0.0151d
+ 5.64c + 6,824, where d was the distance traveled (miles) and c the cost of glass ($). In the same
way, the equation for total GWP was 0.00111d + 0.486c + 5,880.
Overall, the standard error in doing this assessment for # of books is much greater than in
doing the same for the cost of glass and transportation distance for e-reader. This means that the
# of books is much sensitive with respect to the impact criteria.
Sensitivity Analysis Three different input variables were considered for the sensitivity analysis. Two of these
variables were from the life cycle analysis of the e-reader, and the third variable was from the
paper book life cycle analysis. All three variables were first tested for global warming potential,
and second for energy input. The first input variable tested for sensitivity was the average
distance to the distribution center traveled by an e-reader. This variable in reality would be
highly variable, since e-readers would be shipped all over the country, changing this variable
significantly. The second variable analyzed was the cost of the glass screen used in e-reader
production. This variable was chosen because the glass screen is an expensive component of the
20 e-reader, so fluctuations in the price could affect the overall analysis. The third variable
considered was the number of books that equal one e-reader. This important variable relates the
two life cycle analyses together.
The sensitivity analyses were calculated using the sensitivity analysis add on tool for
excel provided by the professor. All other variables were held constant while the target variable
was incrementally changed. All six graphs of sensitivity were linear relationships, because the
EIOLCA tool, which is a linear model, was used for the life cycle analysis. Based on the data
produced from the sensitivity analyses, the global warming potential and energy input needed for
paper books is most sensitive to the number of books per e-reader. For the e-reader life cycle
analysis, the output variables global warming potential and energy input were most sensitive to
the cost of glass. This means that changes in the price of glass caused the greatest change in
GWP and energy input. The sensitivity analysis on the number of books that equal one e-reader
is especially important, since reducing this number can cause paper books to have less GWP and
energy input than one e-reader.
Limitations of Current Work Though our assessment is in-depth, it is limited in some areas. One example is our analysis of
the e-reader manufacturing materials. For example, although LCD glass is a major component of
the display screen of an e-reader, other components, such as Li-Ion materials, Graphite, Circuit
Boards Liquid crystal and printed wiring board, are excluded from the LCI analysis. In addition,
most manufacturing companies do not provide information about PVC manufacturing, LCD
supply chain and other raw metals in order to maintain a competitive advantage over their
21 competitors. Therefore we simply used the assumption that the ratio of each components found
for the industry averages to be comparable in terms of material composition for our e-reader.
Another limitation of our analysis is that the sectors chosen for our EIOLCA analysis were
broad and is not necessarily specific for our product of analysis.
A final reason why our analysis does not capture all the attributes of the product is the
fact that we assume that an E-reader can only read books. In reality, an E-reader can also read
journals, magazines, and newspapers. Some more advanced E-readers can also browse the web.
Therefore, our comparison is limited in scope.
Conclusions and Recommendations for further studies We examined two impact categories centered on energy inputs and global warming potentials
released into the atmosphere. Both energy inputs and GWPs are significant for their future
impacts. We established our functional unit as 1100 books used per E-reader. We concede that
this number is high, but we wanted to analyze the effects of using an E-reader to its full capacity.
For further studies, we recommend that analysis be conducted concerning other impact
sectors like water usage, toxics released, and maybe even some cost benefit analysis. However,
much variability exists for pricing. Another recommendation we have is to examine how
changing to renewable energy sources would impact the life cycle impacts of E-readers and
printed books. This would certainly reduce the GWPs emitted, but not necessarily the energy
inputs. Our final recommendation for further analyzing this area is in the realm of disposal. In
this study, we had difficulty finding data for disposal and thus assumed the amounts of energy
inputs and GWPs emitted per E-reader was negligible. We did factor in some disposal data for
22 books yet did not include recycling because recycling is not a hugely utilized sector currently in
book printing industry.
Overall, what we found in our life cycle assessment of E-reader to the equivalent 1100 books
was that for both sectors of analysis, energy inputs and GWPs, the E-reader performed better.
However, as discussed in our sensitivity analysis there are a number of factors that can vary to
change that finding. Most notably, changing the number of books read per E-reader has a
significant impact. It would take a very low number of books read per E-reader to make that
option more appealing in terms of energy inputs. We conclude though that currently an E-reader
is a better option.
23 References •
Ackerman, Frank. Massey, Rachel. (2003) “The Economics of Phasing Out PVC”
•
Borggren C; Moberg, A; Finnveden G “Books from an environmental perspective – Part
1: environmental impacts of paper books sold in traditional and internet book stores”
International Journal of Life Cycle Assessment 2011 16:138-147
•
Caudill, R. (2000) “A Lifecycle Environmental Study of the Impacts of E-Commerce on
Electronic Products.” IEEE International Symposium on Electronics on Environmental.
Pages 298 – 301
•
Guinee J, Gorree M, Heijungs R, Huppes G, Kleijn R, De Koning A, van Oers L,
Wegener Sleeswijk A, Suh S, Udo de Haes H, de Bruijn J, van Duin R, Huijbregts M
“Handbook on Life cycle assessment: Operational Guide to the ISO standards Series:
Eco-efficiency in industry and science
•
Koch, J., Keoleian, G. (1995) “Evaluating Environmental Performance: A Case Study in
the Flat-Panel Display Industry.” IEEE International Symposium on Electronics on
Environment. Pages 158 – 165
•
Kozak, Greg. (2003) “Printed Scholarly Books and E-book Reading Devices: A
Comparative Life Cycle Assessment of Two Book Options.” Center for Sustainable
Systems. Report No. CSS03-04, pages 1-238
•
Moberg, Johansson, Finnveden and Jonsson (2007) “Screening environmental life cycle
assessment of printed, web based and tablet e-paper newspaper”. Page 13 - 47, 93 - 99
•
Moberg, Asa; Borggren, Clara; Finnveden, Goran. “Books from an environmental
perspective – Part 2: e-books as an alternative to paper books” International Journal of
Life Cycle Assessment 2011 16: 238 – 246
24 •
National Research Council. (1997) "ANNEX 1: LIFE-CYCLE STRESSOR EFFECTS
ASSESSMENT." Wood in Our Future: The Role of Life-Cycle Analysis: Proceedings of
a Symposium.
•
Toffel M, Horvath A, “Environmental Implications of Wireless Technologies: News
Delivery and Business Meetings” Environmental Science & Technology 2004 11: 29612970
•
(2012)
“Lithium
Battery
Calculations.”
Fedex
Express.
http://images.fedex.com/us/services/pdf/LithiumBattery_JobAid.pdf
•
Dean, James, “The Forbidden City of Terry Gou.” Wall Street Journal. Aug. 11 2007.
•
Other websites used:
o
http://www.metalprices.com
o
http://ebook-reader-review.toptenreviews.com/
o
http://www.batteryeducation.com/2008/10/how-many-cells-are-in-a-battery.html
o
http://www.dailyfinance.com/2012/01/18/apple-will-profit-from-doing-the-rightthing/
o
http://online.wsj.com/public/article/SB118677584137994489.html?mod=blog
o
http://www.searates.com/reference/portdistance
o
http://userwww.sfsu.edu/~cholette/sustain/SSCpublic/Wii-Case-andSoftwareTutorial.pdf)
o
http://www.ecolibris.net/
o
http://avgpostageweights.blogspot.com/2010/10/average-weight-of-paperbackbook.html
25 Appendix Appendix A: Flow Charts Figure A1: Preliminary Flow Diagram of Book Production
Figure A2: Preliminary Flow Diagram of E-Book Production
26 Appendix B: Life Cycle Inventory Analysis Table A1. Life Cycle Inventory Analysis for Printed Books (1100 books)
Unit Processes
Sub-Unit Process
Book Use
Recycling
Weight (kg)
Reading/Storage
Paper Recycling
Disposal
Distribution
Manufacturing
Wood
Ink (microliters)
Energy
Other Materials
Fuel(gal)
Packaging Materials
Cardboard
Plastic
Circulation
Manufacturing
Distribution
Energy Input [MJ]
864
173
691
864
2591
2012
5670
0
0
22
6
2
4
0
0
831.6
2944
36019
2394
0
33625
0
2944
240
96.4
143.6
39795
Total
GWP [kg]
0
0
61.16
571
4800
3024
0
1440
0
571
0.165
0.136
0.029
5433
Table A2. Life Cycle Inventory Analysis for E-reader
Unit Processes
Sub-unit Processes
E-Reader Use
transportation
packaging
Power Generation
Supply
manufacturing
product travel
Cardboard
Cable
Battery
Adaptor
Chassis
LCD Screen
Power Generation
Supply
PVC
Copper
Aluminum
Lithium
Iron
Copper
Zinc
PVC
Glass
Transportation
Packaging
Manufacturing
Cable Production
Battery Production
Electronic
Production
Chassis Production
Screen Production
Total
Energy Input
[MJ]
GWP CO2e
[kg]
&
Total
Weight
(g)
402.7
-
32.25
17.86
6737
2354.5
0.748
2682333.5
&
338.38
338.38
402.7
30.12
31.75
166.53
67.68
42.3
-
101.591088
32.25
17.86
3.207
4.37
1.413
1.961
36.740088
53.9
6098.1012
2.354
0.748
190.8
660
125.8
275.6
3165.9012
1680
15.66
14.46
31.31
0.459
143.22
23.31
10.83
56.84
42.3
741
0.587
2.62
3.86
0.51
0.601
0.812
0.431
1.53
36.740088
6889.2
35.8
155
264
396
54.9
70.9
32.6
243
3165.9012
2690.8
27 Appendix C: E-­‐book Materials Cost Inventory Table A3. Cost analysis of e-reader manufacturing
PVC Copper Aluminum Lithium Iron Zinc Glass Total Weight (kg) 0.0725 0.03777 0.03131 0.000459 0.14322 0.01083 0.0423 Price ($/KG) 2.53 8.5 2.52 62.9 0.14 2 154 Cost ($) 0.1834 0.3210 0.0789 0.0289 0.02 0.0217 6.5142 Total 0.338389 -­‐ 7.1681 Appendix D: Life Cycle Impact Analysis Graphs Life Cycle Impact Analysis 45000 40000 35000 30000 25000 20000 15000 10000 5000 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 6889.204842 2690.786815 Book 39795.0244 5432.509003 Figure A3. Total Life Cycle Impact Assessment
28 Disposal Impact Analysis 900 800 700 600 500 400 300 200 100 0 Energy Input [MJ] GWP CO2e (kg) 0 0 831.6 61.16 E-­‐Reader Book Figure A4. Disposal Impact Analysis
Use Impact Analysis 8000 7000 6000 5000 4000 3000 2000 1000 0 E-­‐Reader Book Energy Input [MJ] GWP CO2e (kg) 6737.5 2682.3335 0 0 Figure A5. Use Impact Analysis
29 Distribu8on Impact Analysis 3500 3000 2500 2000 1500 1000 500 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 50.11375413 2355.214213 Book 2943.970282 571.4912725 Figure A6. Distribution Impact Analysis
Manufacturing Impact Analysis 40000 35000 30000 25000 20000 15000 10000 5000 0 Energy Input [MJ] GWP CO2e (kg) E-­‐Reader 101.591088 6098.1012 Book 36019.45412 4799.85773 Figure A7. Manufacturing Impact Analysis
30 Appendix E: Sensitivity Analysis Sensi8vity Analysis GWP of Number of Books for Paper Book LCA
16000 14000 GWPs (CO2e) 12000 10000 8000 6000 4000 2000 0 0 500 1000 1500 2000 2500 3000 # of books Figure A8. Sensitivity Analysis GWP Number of Books for Paper Book LCA
Sensi8vity Analysis for Energy Input of Number of Books for Paper Book LCA energy input (MJ) 100000 80000 60000 40000 20000 0 0 500 1000 1500 2000 2500 3000 # of books Figure A9. Sensitivity Analysis for Energy Input of Number of Books for Paper Book LCA
31 Sensitvity Analysis for GWP for Average Distance to Distribu8on Center for E-­‐reader LCA 12000 GWP CO2e [g] 11000 10000 9000 8000 7000 6000 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Average Distance to DistribuRon Center (mi) Figure A10. Sensitivity Analysis GWP for Average Distance to Distribution Center
Sensitvity Analysis for Energy Input for Average Distance to Distribu8on Center for E-­‐reader LCA 210 200 Energy Input [MJ] 190 180 170 160 150 140 130 0 500 1000 1500 2000 2500 3000 3500 4000 Average Distance to DistribuRon Center (miles_ 4500 5000 Figure A11. Sensitivity Analysis Energy for Average Distance to Distribution Center
32 Sensitvity Analysis of Energy Input for Cost of Glass for E-­‐
reader LCA 280 260 Energy Input [MJ] 240 220 200 180 160 140 120 0 5 10 15 20 25 Cost of Glass ($) Figure A12. Sensitivity Analysis GWP for Cost of Glass
Sensitvity Analysis of GWP for Cost of Glass for E-­‐reader LCA 15000 GWP CO2e [g] 13000 11000 9000 7000 5000 0 2 4 6 8 10 12 14 16 18 20 Cost of Glass ($) Figure A13. Sensitivity Analysis Energy for Cost of Glass
33 120 RiskSim 2.42 Trial for EvaluaRon -­‐ Histogram RiskSim 2.42 Trial for EvaluaRon -­‐ Histogram Frequency Frequency 100 200 80 150 60 100 40 50 20 0 0.00 5000.00 10000.00 15000.00 20000.00 25000.00 30000.00 0 Output Base
Min40000 Max
Min_val
Base_case
Max_val
Distribution
0 20000 60000 80000 100000 120000 140000 160000 180000 200000 Appendix F: Uncertainty Analysis Uncertainties in Books Units
# of Books
Total GWP
emissions
Energy Input
Books
g
Value
1100
2%
500%
22
Output 1100
5500
Triangular
MJ
Random
4487.845411
22165.47
162356.7834
Monte Carlo Assessment for GWP (kg) Mean
St. Dev.
Mean St. Error
Minimum
First Quartile
Median
Third Quartile
Maximum
Skewness
10922.52
5815.34
183.90
186.84
6371.26
10095.06
14902.96
26461.51
0.4597
CumulaRve Probability RiskSim 2.42 Trial for EvaluaRon -­‐ CumulaRve Chart 1.0 0.8 0.6 0.4 0.2 0.0 0.00 5000.00 10000.00 15000.00 20000.00 25000.00 30000.00 Output Monte Carlo Assessment for Energy (MJ) Mean
St. Dev.
Mean St. Error
Minimum
First Quartile
Median
Third Quartile
Maximum
Skewness
80004.83741
42595.98035
1347.003171
1368.567098
46667.93123
73943.88793
109160.6702
193824.2876
0.4597
34 RiskSim 2.42 Trial for EvaluaRon -­‐ Histogram Frequency 150 100 50 CumulaRve Probability RiskSim 2.42 Trial for EvaluaRon -­‐ CumulaRve Chart 0 2637.5 2638 2638.5 2639 2639.5 2640 2640.5 2641 2641.5 2642 2642.5 1.0 0.8 0.6 0.4 0.2 0.0 Output 0 20000 40000 60000 80000 100000 120000 140000 160000 180000 200000 Output Uncertainties in E-­‐books Units
Cost of Glass
Distance of
transportation
Total GWP emissions
Energy
$
miles
kg
MJ
Base Value
Min
Max
Min_val
Base_case
Max_val
Distribution
6.5142
10%
110%
0.65142
6.5142
7.16562
Triangular
5.221
1877.273
#REF!
#REF!
50%
150%
938.6365
1877.273
2815.9095
Triangular
1634
2640
6878
Monte Carlo Assessment for GWP (kg) Mean
St. Dev.
Mean St. Error
Minimum
First Quartile
Median
Third Quartile
Maximum
Skewness
2640.39
0.85
0.03
2637.78
2639.79
2640.46
2641.01
2642.23
-0.3205
CumulaRve Probability RiskSim 2.42 Trial for EvaluaRon -­‐ CumulaRve Chart 1.0 0.8 0.6 0.4 0.2 0.0 2637.50 2638.00 2638.50 2639.00 2639.50 2640.00 2640.50 2641.00 2641.50 2642.00 2642.50 Output 35 Random
RiskSim 2.42 Trial for EvaluaRon -­‐ Histogram 200 Mean
St. Dev.
Mean St. Error
Minimum
First Quartile
Median
Third Quartile
Maximum
Skewness
Frequency Monte Carlo Assessment for 150 Energy (MJ) 6879.342801
10.33769308
0.326906559
6850.03835
6872.369879
6879.624959
6887.045231
6902.434963
-0.2419
100 50 0 6850 6860 6870 6880 6890 6900 6910 Output CumulaRve Probability RiskSim 2.42 Trial for EvaluaRon -­‐ CumulaRve Chart 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 6850 6860 6870 6880 6890 6900 6910 Output 36