Scanning Life Cycle Assessment of Printed and E-paper Documents based on the irex Digital Reader

Transcription

1 Scanning Life Cycle Assessment of Printed and E-paper Documents based on the irex Digital Reader March 2009 Sebastiaan Deetman Ingrid Odegard Supervisors: Rene Kleijn at CML Vincent Locht at irex Technologies

2 Preface This report was written by Sebastiaan Deetman and Ingrid Odegard, students of the master programme Industrial Ecology a collaboration of the University of Technology in Delft and Leiden University. The Institute of Environmental Sciences (CML), part of Leiden University, is experienced in performing Life Cycle Assessments (LCA), drs. Rene Kleijn at CML supervised this project. It should be kept in mind that this is a scanning LCA done by students. The project was commissioned by irex Technologies, a newly developing Dutch Digital Reader company. We would like to thank Vincent Locht of irex Technologies very much for giving us the opportunity to do this study and for his help throughout the project. Our thanks also go out to Rene Kleijn, Reinout Heijungs and Lauran van Oers for giving us more insight into LCA and helping us out when necessary. March, 2009 Sebastiaan Deetman and Ingrid Odegard 2

3 Executive Summary Paper use does not only create a problem of wastes and exploitation of natural resources, but also has a significant impact on global warming [Counsell, 2006]. Recently electronic reading devices based on electronic ink or e-paper technologies have been introduced as an alternative to paper use. The goal of this study is to compare the global warming potential (GWP) of the service an irex Digital Reader provides to the same service if provided by an office printer. The comparison is based on a screening Life Cycle Assessment (LCA), a form of the scientific tool which assesses the environmental impact of a product or service throughout its life cycle. The functional unit used in this study is the service of one year of office paper use. In this study it was assumed that the irex DR will substitute all paper printouts made by the office worker. Two alternative were used in this study; one in which printing is done on LWC (light-weight coated) paper and one in which printing is done on woodfree uncoated paper. Furthermore, two scenarios were made, to be able to calculate a break-even point. The two scenarios represent the cases in which an office worker either prints 2000 pages a year, or pages a year, which is the maximum amount possible when the printer is shared between 30 office workers. The Global Warming Potential (GWP) in CO 2- equivalents of both alternatives and both scenarios, compared to the GWP of the irex DR are shown in the table below (Table 6 in Chapter 4). GWP (CO 2 equivalents) Scenario 1 Scenario 2 Printing 2000 pages per year Printing pages per year irex Alternative 1 Printing with LWC paper Alternative 2 Printing with woodfree uncoated paper The figure below (Figure 3 in Chapter 4) shows the break-even point calculation. It shows that the break-even point is reached much sooner than the consumption of an average office worker of 10,000 prints per year. The break-even points are about 5000 prints per year for woodfree uncoated paper and slightly over 3000 prints per year for LWC paper. Break-even Point for the Office Worker GWP (kg CO2-eq.) Number of prints per year irex LWC woodfree uncoated 3

4 These results provide strong evidence that the irex Digital Reader may be a sound alternative to regular office paper use, considering impacts on climate change. This conclusion must however be seen, within the limited context of this scanning LCA study. During the evaluation (chapter 5) it was found that the most important uncertainty is created by the definition of the display module in the irex DR. Extensive specifications where missing on this product component, and a best estimate was used, which turned out to be responsible for ca. 33% of the climate change impacts. Global Warming Potential was the principal interest of irex Technologies. However, LCA does give insight in other environmental impacts as well. It was decided to compare the use of an irex for one year to a typical office worker scenario for other environmental impacts as well; the scenario in which woodfree uncoated paper is used and 10,000 prints per year are made. As the table (Table 9 in Chapter 4) below shows, the irex DR scores better on all impact categories than the typical office worker scenario. Label Category irex DR one year use 10,000 prints woodfree paper, laser jet, b/w, print Unit [C1] Land use competition m2a [C3] Eutrophication potential kg PO4-Eq [C5] Resources depletion (abiotic) kg antimony-eq [C14] Acidification potential (average European) kg SO2-Eq [C17] Photochemical oxidation (summer smog) kg ethylene-eq [C29] Terrestrial ecotoxicity kg 1,4-DCB-Eq [C30] Ionising radiation 1.18E-7 6.8E-7 DALYs [C34] Marine aquatic ecotoxicity 3.15E4 4.82E4 kg 1,4-DCB-Eq [C38] Freshwater aquatic ecotoxicity kg 1,4-DCB-Eq [C46] Stratospheric ozone depletion 7.78E E-6 kg CFC-11-Eq [C50] Human toxicity kg 1,4-DCB-Eq [C56] Climate change GWP 100a (biogene kg CO2-Eq corrected) 4

5 Table of Contents Preface... 1 Preface... 2 Executive Summary Introduction Goal and Scope Definition Goal of this Study Scope of this Study Function Functional Unit Impact Categories Interpretation Data Inventory Analysis Inventory for the irex Digital Reader Production of Components Use Transportation and Packaging Disposal Print Alternative The Use of a Printer LWC Uncoated Woodfree Paper Paper disposal Allocation Impact Assessment Break-even Point: GWP Other Impacts Evaluation & Interpretation Packaging Materials E-paper Screen Summary of Assumptions Concluding remarks Literature Appendix 1 Definition of CMLCA Processes

6 List of Abbrevations CH CML CMLCA DR g h GLO GWP LCA LDPE LWC Pb PWB RER SMD t tkm UCTE WEEE WB Switzerland Centre of Environmental Sciences, Leiden Life Cycle Assessment software Digital Reader gram hour Global Global Warming Potentila Life Cycle Assessment Low Density Polyethylene light-weight coated Lead Printed Wiring Board Europe Surface-mounted device tonne tonnekilometer Union for the coordination of the transmission of electricity Waste Electrical and Electronic Equipment Wiring Board List of Figures Figure 1: Methodology for defining component weights Figure 2: Process diagram, specification of paper disposal process including recycling Figure 3: Break-even point for the office worker List of Tables Table 1: Characteristics of base case and alternatives... 9 Table 2: Component inventory and categorization Table 3: Transportation stages Table 4: Characteristics for use of printer Table 5: Market values used in economic allocation, for scenario of 2000 prints per year and for scenario of prints per year per office worker Table 6: Impact in Climate Change of office paper use for different alternative, in CO 2 -eq.. 19 Table 7: Allocation values for break-even points and the 'typical office worker scenario Table 8: Impacts of irex DR compared to impacts at the two break-even points Table 9: Impacts of irex DR compared to impacts at 10,000 prints per year Table 10: Process inflows of production of irex DR 1000 [P3950] Table 11: Process inflows of irex stylus [P3955] Table 12: Proces inflows of LCD module irex, at plant [P3951] Table 13: Process inflows of use of irex DR 1000 for one year [P3952] Table 14: Process inflows of use, printer with woodfree paper, laser jet, b/w, per h Table 15: Process inflows of use, printer, with LWC paper, laser jet, b/w, per h Table 16: Process inflows of irex packaging at regional plant [P3954] Table 17: Process inflows of paper disposal process, general [P3956]

7 1. Introduction Even though the world is currently shifting from a paper-society to an electronic society, paper is still used in abundance. Paper use does not only create a problem of wastes and exploitation of natural resources, but also has a significant impact on global warming [Counsell, 2006]. Recently electronic reading devices based on electronic ink or e-paper technologies have been introduced as an alternative to regular paper use. The functioning of such e-paper devices is based on electrophoretic display technology, using laminated plastic micro-capsules with carbon and titanium dioxide based pigment particles that get attracted or repelled to applied charges, thus creating a static image. Since the image is maintained without applying a current, this displaying technology has notably lower power consumption than other diplays such as LCD, but provides the image to the eye with the ease and comfort of reading real paper. Thus e-paper devices may possibly represent a sustainable solution to our current paper-society. This claim has been supported by the work of [Moberg et al., 2007] for the comparison between the use of a regular and an electronic newspaper through an e-paper device. Besides newspapers however, other important contributors to the total environmental impacts of paper use, replaceable by the use of e-paper devices such as office paper use or plain books, have not been considered in prior assessments. In this study the life cycle impact of regular office paper use to the use of an e-paper device specifically designed for an office public, the irex Digital Reader 1000 is compared. This e-paper device was developed by irex technologies, located in Eindhoven, the Netherlands, who commissioned and approved the execution of this study [irex, 2009]. The comparison is based on a screening Life Cycle Assessment, a form of the scientific tool which assesses the environmental impact of a product or service throughout its life cycle. A number of complementing environmental impact categories reflect the impact of a product on the natural environment, all through its life cycle. irex Technologies is mainly interested in the global warming potential of its digital reader, compared to printing documents on paper. Accordingly, in this study the main interest lies with climate change as an environmental impact category. Based on this single indicator, the implicit question is raised whether the Digital Reader as a representative of e-paper is an environmentally sound alternative to regular office paper use. As a rough reference the average paper use of an office worker is generally perceived to be in the order of prints, or 50 kgs of paper per year [MPCA, 2009] and [University of California, 2009]. Two scenarios were assessed for the impact calculation on office paper use; one with a low annual paper use of 2000 prints, and one with a high annual paper use of over 12,000 printouts. Secondly, two alternatives where defined with respect to the type of paper used; Light Weight Coated paper representing a high quality type of paper, and uncoated woodfree paper representing a more regular grade. In the following chapter, the goal and scope of this study are defined, together with the full basis of comparison. Chapter 3 discusses the process of collecting and converting data on the component, transport, energy, and disposal requirements of the regular and digital office paper use. Readers interested in the results of this study are referred to Chapter 4, and to Chapter 5 for their interpretation. Chapter 6 holds the concluding remarks and recommendations for this study. 7

8 2. Goal and Scope Definition This LCA study was carried out at the Centre of Environmental Science in Leiden, by two master students of Industrial Ecology. The study was commissioned by irex Technologies, a newly developing Dutch digital reader company. In order to be able to claim environmental friendliness of their product, an LCA was proposed. Moberg et al. [Moberg, 2007] has already studied the environmental impact of a prior irex e-paper product the Iliad comparing the function of downloading newspapers to read on e-paper to reading newspapers in paper form, which showed a better result for e-paper than for newspaper. The new product line of digital readers by irex Technologies targets the office worker as potential consumer, and therefore aims at substituting reading documents on e-paper for printing office documents. 2.1 Goal of this Study The goal of this study is to compare the global warming potential (GWP) of the service an irex Digital Reader provides to the same service if provided by an office printer. As stated in the introduction, an average office worker prints out a number of 10,000 pages a year. This study will compare the environmental impact of printing out those pages to reading them on an irex Digital Reader. This study is a scanning LCA, done by students in a limited time period and therefore the results of the study should be used carefully and may be interpreted as a result of a limited scanning LCA only. Supervision was done by drs. R. Kleijn at CML. In this study the environmental impact of the irex Digital Reader (DR) 1000 will be compared to the reference flow printed paper. The main environmental interest of irex is climate change. Therefore, this will be main focus in this study. However, because other impact categories are also important for electronic products, some attention will be paid to the other baseline LCA impact categories. 2.2 Scope of this Study Several key LCA components as they were used in this study will be elaborated on below: the function of the product which is analysed, the functional unit which was used to compare services, a description of the life cycle of an irex DR as it was used here, the sensitivity analyses which were performed and the data which was used Function The irex DR can be used to read documents, uploaded from a computer, and to make notes, even in a document. These are the functions which were analysed in this study. It can, however, also be used to read newspapers and books. These functions were not included in this study, but it is reasonable to assume that adding these functions in a more elaborate LCA study would decrease the DR s supposed environmental impact. The notepad function does make the comparison of e-paper with printed documents viable, because of the possibility to add and save one s own notes to the document. The time required to send a document from a personal computer to a printer was assumed equal to the time required to download that document from a PC to the Digital Reader, so that the environmental impacts resulting from the intermediate use of a desktop computer could be 8

9 excluded from the scope this study. The additional function of a wireless internet connection, and thereto related the function of downloading documents directly to the DR was not included in this study. The related services, e.g. server space and preparation of document to fit the DR format, were therefore neglected Functional Unit The functional unit used in this study is the service of one year of office paper use. In this study it was assumed that the irex DR will substitute all paper printouts made by the office worker. Several assumptions needed to be made, implicitly included in the functional unit: The life span of an irex DR is equal to the warranty period of two years The DR is recharged once a day Recharging once a day will be sufficient for one day s use The reference flow is one year of office paper use. Several assumptions were made with regard to printing of paper. Furthermore, two different alternatives were chosen, shown in Table 1. Use of LWC paper is automatically assumed in the Ecoinvent database, however, the database also states that wood-free un-coated paper is the standard paper used in offices. In Paragraph 3.2 the specifics of the alternatives will be elaborated on. Based on the Ecoinvent database and its accompanying reports, it remains unclear whether the defined process takes the possibility of double sided printing into account. We assume the toner use is based on an average value for single and double sided printing. Table 1: Characteristics of base case and alternatives Base Case Alternative 1 Alternative 2 irex DR 1000 Laser printer (standard Ecoinvent), capacity of prints per year Laser printer (standard Ecoinvent), capacity of prints per year One DR per office worker Printer shared with 30 office workers Printer shared with 30 office workers Image is black and white (with Prints are black and white Prints are black and white greyscale LWC paper woodfree un-coated paper Lifetime of irex: 2 years Lifetime of printer: 4 years Lifetime of printer: 4 years Outcomes for two printing scenario s were calculated, which resulted in the definition of two break-even points. The scenarios define the impact for the range between 2000 prints per office worker per year and prints per office worker per year. The allocation method and values used can be found in Paragraph 3.3, specifically Table 5. Because allocation is based on market values, the allocation factors change when a different number of prints is made. The allocation-factors at the break-even point are calculated in Paragraph 4.2, Table 7. In either alternative the lifetime of the printer is 4 years. Because CMLCA assigns part of a printer to an hour of printing, and thus to a number of prints made, this value is different in the two scenarios Impact Categories As stated above, irex Technologies is mainly interested in the impact category Global Warming. The specific impact category used in CMLCA is Climate Change_GWP 100a(CO2 biogene and resource GWP=1, NMVOC average) [GLO]. This impact category gives the score for Global Warming Potential for a 100-year time horizon in kg CO 2- equivalents. The Climate Change impact category for which a biogene correction is included was chosen because wood used to produce paper absorbs CO 2 from the environment. If the 9

10 biogenic correction is not included, this absorption would be neglected and would subsequently yield an unrealistic result for the paper alternatives. Even though irex Technologies is primarily interested in their impact on Global Warming, it remains interesting to see how the irex DR impact compares to the impact of a typical office worker, printing 10,000 pages a year. This is shown in Table 9, in Paragraph Interpretation Two analyses will be carried out. The first determines the impact of the amount of packaging on the final score on the impact category Climate Change. This can be seen as a contribution analysis coupled to a perturbation analysis. The second analysis will determine how the choices made to include the e-paper screen, the Wacom board affect the result of the study. This is a new technology and therefore it is not included in the Ecoinvent database yet, and hence assumptions had to be made. Chapter 4 elaborates on these analyses Data Data on the technology used in the irex DR was supplied by irex, and in case of missing data supplemented with data from the Ecoinvent database and internet search. Data was supplied by irex as a data table in Microsoft Excel and additional documentation on component specifications in.pdf format (both not included in this report due to confidentiality). These pdf files were composed by manufacturers. Ecoinvent processes were chosen as representing Europe [RER], where possible. Otherwise, respectively either a global [GLO] or a Swiss [CH] representative was chosen. 10

11 3. Inventory Analysis Information used to determine the inventory inputs for the production of components as well as of the use phase of the irex Digital Reader was mainly based on data tables supplied by irex, together with additional assumptions as described in Paragraph and below. For the inclusion of inventory inputs for the disposal phase as well as transportation and packaging inputs, assumptions where made, which are discussed in Paragraph and The inventory analysis for the compared alternative of office printouts is discussed in Paragraph 3.2. The derived inventory inputs where translated to pre-defined sub-processes of the available Ecoinvent 2.0 database. For most of the components and processes this was very well possible due to the extensive number of detailed electronics processes included in the quite recent version of the Ecoinvent database. 3.1 Inventory for the irex Digital Reader The data inputted in CMLCA for the production of components, use, disposal, transportation and packaging related to an irex digital reader will be described in the paragraphs below Production of Components An extensive analysis of the list of plastic and electronic components, supplied by irex as a data table in Microsoft Excel and additional documentation on component specifications in.pdf format (both not included in this report due to confidentiality) was performed. The number of components was given in all cases. The weight, however, was not always retrievable, especially in the case of the smaller electronic components such as capacitors and integrated circuits (IC s). In that case, an estimation of the weight was if possible based on the dimensions given in the specification, multiplied by a conversion factor derived from Ecoinvent background reports. If even that information was unavailable, the total weight was based on the average of a part according to the Ecoinvent database. An example of this method as hypothetically elaborated for memory IC s is shown in Error! Reference source not found.. Source Knowledge Outcome irex data table The Digital Reader contains 5 memory type IC s, 2 of company A, 2 of company B and 1 of company C.????? Component specifications IC s from company A weigh 2 gram, those from company B have a surface of 2 by 1 cm, any specifications from company C are missing. 2 g 2 g 2 cm 2 2 cm 2? Ecoinvent reports The weight of an average memory IC is 1,5 gram, this is based on a average weight of 7 kg/m 2 of IC chip. 2 g 2 g 1,4 g 1,4 g 1,5 g Figure 1: Methodology for defining component weights 11

12 Structurally applying this method, the weights of almost all product components were determined and categorized into pre-existing datasets of the Ecoinvent database. The result of this component inventory and categorization is shown in Table 2. In the case of the printed wiring board a conversion factor of 1.63 kg per m 2 of PWB was used. The square weight of a general computer wiring board defined in Ecoinvent is 3.26 kg/m 2. Since fine electronics use more sophisticated boards, half the square weight was assumed. Table 2: Component inventory and categorization Component category Ecoinvent type Quantity Total weight (g) Chips & IC's Capacitors Resistors Diodes Inductors Transistors Connectors Batteries Plastics Printed WB Other IC memory-type IC logic-type Capacitor SMD-type Tantalum Capacitor Resistor SMD-type Diode, glass, SMD-type LED Miniature RF chip-type Transistor SMD-type (mod.) Ribbon cable parts (mod.) Battery, Li-Ion ABS/PC PWB, surface mount, Pb-free Wacom sensor board PET, bottle grade Printed WB Optical components: TFT+E-ink Module LCD, irex Stylus Transistor Capacitor Polystyrene (general purp.) Antennas Unknown Crystals and resonators Electromechanical components Filters Unknown Unknown Unknown Total

13 As can be seen from the table above, only a few components in the categories crystals and resonators, electromechanical components and filters where not accounted for due to lack of information. Since these are generally minuscule components, it was decided to ignore this incompleteness in the impact analysis. A total weight of up to 635 grams has been specified and declared to product parts. This deviates from the 570 grams, given as the total weight of the digital reader according to commercial information of irex [irex, 2008]. The difference is explained by the fact that in the commercial weight indication, the stylus (responsible for ca. 25 grams) as well as some advanced components for future versions of the reader where not included. Since they are included in the data-sheet and thus in the analysis, the total accounted weight was found to be in accordance with the expected value, and thus acceptable for further analysis. One of the very typical components of the digital reader is the e-paper screen, consisting of a 10.2 TFT display, an E-ink module and a Wacom sensor board. As can be seen from Table 2, the components of the Wacom sensor board were specified separately based on its technical documentation. However, a standard E-ink display module does not exist in the Ecoinvent database, so further assumptions had to be made to credibly include this component in the inventory analysis. Since it is such an essential characteristic of the considered product, representing the display by an average unspecified electronic component did not seem as a satisfying solution (e.g. as is done by [Lehmann, 2007] in Ecoinvent report 18, page 179). It was decided to define a irex display module, based on an Ecoinvent LCD display module (LCD module, at plant[glo]) in which the backlighting was taken out. The average composition was corrected for the loss of the weight of the backlighting, and 66 grams of this irex specific display module where added to the inventory. Aside from the digital reader components listed above, a power adapter, needed to charge the digital reader, was included as a necessary product part. The only power adapter available in Ecoinvent is specified for a laptop computer. Since the Ecoinvent adapter is not expressed in weight, but as a single unit, and since laptop adaptors are generally bigger than those for smaller appliances, the ratio of the irex adaptor weight (26 grams) to a typical laptop adapter weight (450 grams) was used to correct for the difference. Accordingly, 28% of a laptop adaptor was assumed to represent the actual irex adaptor Use Impacts during the use phase are fully based on the electricity use for charging, so no additional use of accessories or for instance display cleaning chemicals during the use phase where included. The electricity use calculation is based on the assumption that for every office day the digital reader is fully charged during a charging period of two hours, during which it uses 5 Watt hours (Wh). The average working period of 46.2 weeks per year and 6 days per week because one may want to be able to read office documents for at least one day during the weekend was used to complete the calculation. This comes down to a total energy use of 1.39 kwh per year. This energy demand is assumed to be supplied by the Dutch grid, and represented by using the Electricity mix[nl] from the Ecoinvent process database. 13

14 3.1.3 Transportation and Packaging The components directly included from Ecoinvent are mostly defined up to the point of their storage at their final assembly or production plant. Since the digital reader is currently assembled in Eindhoven, the Netherlands, and distributed to local retailers, assumptions for several transport distances as well as means of transport had to be made. These assumptions include the transportation of assembly components and packaging as well as the distribution to retailers. The necessary transportation stages included in this study are summarized together with their specific assumption in Table 3. Table 3: Transportation stages Transportation stage Components production plant to assembly site in Eindhoven Packaging production plant to assembly site irex distribution to retailers Assumptions (for each finished reader) g. of packaged electronic components come from eastern Asia (10000 km). 385 g. of packaged ABS polymers from Germany (500 km). 30 g. of packaging film as well as 30 g. of cardboard are transported over a distance of 500 km twice (component packaging and irex packaging) The finished irex digital reader of 635 g. is transported 100 km to a retailer. Inventory per year of irex use tkm by tanker tkm by rail Ecoinvent transport type used freight, rail[rer] barge tanker[rer] 0.03 tkm by lorry lorry 16t, fleet average[rer] tkm by van van <3.5t[RER] The packaging, as referred to in the table above consists of 2 types of packaging included in the inventory. First of all, the packaging of the components to be delivered to the assembly station in Eindhoven was assumed to consist of 10% of the transported component weight based on a rough estimation during a visit at the irex assembly site. Since all components together weigh the same as the total of the finished digital reader, this adds up to 63.5 grams of packaging material, assumed to be composed of plastics and cardboard, both 50% of the total weight of the packaging material. The Ecoinvent processes used accordingly are packaging film, LDPE, at plant [RER] for the plastic packaging and packaging, corrugated board, mixed fibre, single wall, at plant [RER] for the cardboard proportion. Secondly, the commercial packaging of the irex digital reader, in which the product is supplied to the retailer, is calculated similarly. Because of this, another 30 grams of both LDPE packaging film and corrugated board is added to the inventory for the digital reader. 14

15 3.1.4 Disposal Since no standard electronics disposal handling process is defined in Ecoinvent, it was assumed that the disposal of the irex digital reader is comparable to that of an LCD flat screen, since it contains many of the components typical to the digital reader, like an TFT module, a variety of electronic components and a polymer frame. A correction was made for the average weight for the 17 inch LCD flat screen defined by the Ecoinvent database, being 5,1 kg [Lehmann, 2007, page 105], by including only the fraction (0,635/5,1) of the full LCD flat screen disposal process (WEEE treatment), which represents the weight of the digital reader. Disposal of the power adapter is included according to the corresponding process of dismantling and connected treatment for a regular power adaptor by including the standard Ecoinvent process dismantling, power adapter, external, for laptop, to WEEE treatment. Again, only 28% of a standard module is accounted for, according to the calculation in Paragraph Disposal of the packaging material is accounted for by assuming the packaging is delivered to municipal incineration. Since this pathway is only available in Ecoinvent based on data for Switzerland, this was included as a best estimate. The cardboard fraction is treated according to disposal, packaging cardboard, 19.6% water, to municipal incineration [CH] and the plastic fraction according to disposal, polyethylene, 0.4% water, to municipal incineration [CH]. This is based on the assumptions made in the previous paragraph. 3.2 Print Alternative The functional unit used in this study is the service of the use of office paper for a year, as described in Chapter 2. The paper-based alternative to be compared to the results of the abovementioned inventory for the digital reader will thus have to fulfil the same service. To define the inventory for this service based on the use of a typical office printer, the use of the laser printer, black toner, as well as the printing paper, necessary transportation, operating electricity and disposal processes where accounted for. Since the use of paper is responsible for a significant part of the total impacts, the choice of the type of paper used may significantly influence the balance of the comparison. Two alternatives were therefore defined based on the use of different paper types; one using LWC paper and one using woodfree uncoated paper. The basis of the contribution for the use of the printer, toner, transport and electricity consumption remain the same over these two alternatives and are discussed in Paragraph The basis for the comparison of the use of two different paper sources is elaborated on in the two succeeding paragraphs. In Paragraph the assumptions for the waste disposal processes are explained The Use of a Printer The Ecoinvent database contains a pre-defined process description for an office laser printer as well as a process description for the use of it. This process description includes all the necessary information like the life-time of the printer, its energy use during 3 different operational modes (active, stand-by and off), the print speed and average paper consumption. 15

16 These numbers were all converted to an average inventory for an hour of printer use, as summarized in Table 4Error! Reference source not found. below [Lehmann, 2007]. Table 4: Characteristics for use of printer Process/part description Amount (per hour of printer use) Unit Ecoinvent name Electricity use kwh Electricity, low voltage, production UCTE, at grid [UCTE] Printing paper Alternative 1: kg Paper, woodcontaining, LWC, at regional storage Alternative 2: kg [RER] Paper, woodfree, uncoated, at regional storage [RER] Laser printer Scenario 1: 1.78E-4 piece Printer laserjet, b/w, at plant [GLO] Scenario 2: 2.85E-5 piece Printer laserjet, b/w, at plant [GLO] Toner kg Toner, black, used for printing [RER] Transport tkm Transport lorry 16t, fleet average [RER] tkm Transport, freight, rail [RER] As can be seen in Table 4 the amount of printer used per hour depends on the scenario. Because Ecoinvent states that the lifetime of a printer is four years, the fraction of the printer used, in a situation in which not the maximum amount of pages is printed, becomes higher LWC LWC paper light-weight coated paper is the paper used in printing work with higher quality demands, like journals and magazines [Hischier, 2007]. Since this is the pre-specified paper type used in the Ecoinvent database, it was decided that one of the alternatives should at least be based on this paper type, to guarantee the consistency within the comparison with the irex, which was also mainly based on pre-specified Ecoinvent processes. This type of paper was used in the first alternative. The module includes the European production of LWC paper including transports to paper mill, wood handling, mechanical pulping and bleaching, deinking of waste paper, paper productions, energy production on-site and internal waste water treatment [Hischier, 2007, page 124] Uncoated Woodfree Paper The Ecoinvent database contains a dataset on the production and distribution of an uncoated type called woodfree paper, meaning that it contains at least 90% of fibres in the form of chemical pulp [Hischier, 2007]. Since this paper type is described as the grade used for most of the office papers, it is of specific interest in this study. The module includes: the European production of uncoated woodfree paper in an integrated mill including transports to paper mill, wood handling, chemical pulping and bleaching, paper productions, energy production on-site recovery cycles of chemicals and internal waste treatment [Hischier, 2007, page 124]. This type of paper was used in the second alternative. 16

17 3.2.4 Paper disposal A new flow was defined in CMLCA defining the process of paper disposal. Three paper disposal flows are defined in Ecoinvent: [G139] disposal, paper, 11.2% water, to municipal incineration [CH] [G449] disposal, paper, 11.2% water, to sanitary landfill [CH] [G1984] paper, recycling, with deinking, at plant [RER] These were aggregated into one paper disposal process. The first two processes, however, differ from the third. The disposal processes have as economic outflow the service of the disposal of 1 kg of paper, which is exactly what is desired. The recycling flow has, however as output a physical kilogram of recycled paper. There is no service for recycling paper defined in Ecoinvent, only the process of recycling itself which gives an output of recycled paper. Adding this flow to the printer alternatives means adding a second economic outflow. This means the printer alternatives not only provide the service of one year of printer use in an office, but also produce recycled paper. Therefore, it is necessary to allocate part of the total process to the recycled paper, and part of the total process to the use of the printer. This means that in using a printer you take into account part of the environmental impacts of recycling the paper you produce as waste. How this allocation is handled is described in Paragraph 3.3. The better part of all paper waste is recycled [AF&PA, 2009]. Since paper-waste generation in an office is much more concentrated than in other places, and not a lot of other types of waste are created, it was assumed the majority of office paper is recycled. It was assumed 8% of office paper waste is incinerated, 2% is land-filled and 90% is recycled. The amount of recycled paper had to be adjusted due to the fact that the inflow (in kg) of waste paper is larger than the outflow (in kg) of recycled paper in the recycling process. The process diagram, Figure 2, clarifies the actions taken to include recycling of paper to the use of an office printer. Figure 2: Process diagram, specification of paper disposal process including recycling 17

18 3.3 Allocation Allocation is described by Guinée [Guinée, 2001] as the procedure required to partition the inputs and outputs of all relevant processes to the appropriate product systems. The allocation method recommended by ISO [Guinée, 2001] is economic allocation, which is based on the market value of the economic outflows of the multifunctional process. The two economic outflows under consideration in this study are: Use of an office printer (hour) Recycled paper (kg) Table 5 shows the market values of the relevant products, on which the economic allocation was subsequently based. The data in Table 5 is based on data from Hewlett Packard, Vikingdirect and Nuon [HP, 2009, Vikingdirect, 2009 and Nuon, 2009] Table 5: Market values used in economic allocation, for scenario of 2000 prints per year and for scenario of prints per year per office worker. Cost Use of printer ( ) Price Recycled paper ( /kg) print/yr 292 h/yr pp 2000 prints/yr 46.7 h/yr pp Printer Toner Paper Electricity Total Cost per hour Sources: [Vikingdirect, 2009, Hewlett Packard, 2009, Nuon, 2009] The cost for the use of a printer partially depends on the amount of prints made; toner, paper and electricity are linearly dependent on the number of prints made. The cost of recycled paper is inputted in /kg and therefore remains constant with every scenario. 18

19 4. Impact Assessment In the preceding chapter it was elaborated how the available product and processing information was successfully transformed into a complete inventory dataset. In this chapter the results of the impact assessment will be discussed. This will be done for impacts on climate change in the form of a break-even point calculation in Paragraph 4.1. In Paragraph 4.2 results for other impact categories will be discussed. This study is meant as a comparative assessment only; the comparison between the use of an irex and the use of an office printer for reading documents. Therefore, the results will be limited to the LCA stage of characterisation and no subsequent normalization or weighting calculations are performed. 4.1 Break-even Point: GWP To be able to tell from which total number of prints per person per year an irex Digital Reader becomes an environmentally preferred alternative to printing a break-even point was calculated. This also allows for checking whether this lies below the indicative average office paper use of prints per person per year. Five reference values where calculated for impacts on climate change using Global Warming Potential (corrected for biogene CO 2 uptake) as an indicator. The first of these reference values is the impact of one year s use of an irex Digital Reader. The four remaining ones are calculated according to the two alternatives and the two scenarios defined in Chapter 2. This means that the impacts for the use of a printer by an office worker at a rate of 2000 and a rate of prints per year are calculated for the alternatives of printing on both Light Weight Coated paper as well as on (uncoated) woodfree paper. These values are given in Table 6. Table 6: Impact in Climate Change of office paper use for different alternative, in CO 2 -eq. GWP (CO 2 equivalents) Scenario 1 Scenario 2 Printing 2000 pages per year Printing pages per year irex Alternative 1 Printing with LWC paper Alternative 2 Printing with woodfree uncoated paper A linear relation between the two scenario outcomes (different relation for the two alternatives) was assumed. This allows for the calculation of a break-even point, as can be seen in Table 6Figure 3 below. The impact assigned to the irex digital reader remains constant under the different scenarios, since it was assumed that the digital reader has a virtually endless capacity. This means impacts do not change when more performance is expected (i.e. more documents are read), not even through the marginal electricity use since it was assumed that it has to be charged every office day. 19

20 Break-even Point for the Office Worker GWP (kg CO2-eq.) Number of prints per year irex LWC woodfree uncoated Figure 3: Break-even point for the office worker. Figure 2 shows the break-even points for the use of LWC and woodfree paper. LWC paper has a higher quality than woodfree paper, thus the break-even point is reached sooner, because the impacts per page printed are higher. The break-even points are: slightly above 5000 prints per year for woodfree uncoated paper and slightly above 3000 prints per year for LWC paper. 4.2 Other Impacts Besides the impacts on climate change through emissions of greenhouse gasses as expressed in CO 2 -equivalents in the paragraph above, the CMLCA software, in combination with the Ecoinvent database facilitates insight in other environmental impacts as well. Although these are not the main focus of this study, the results for various other impact categories as described by [Guinée, 2001] are given here as an incentive for contemplation. Allocation factors changes with number of prints made, the values are given in Table 7. Table 7: Allocation values for break-even points and the 'typical office worker scenario. Cost per office worker Use of printer ( ) Woodfree uncoated 5122 prints/ year h Break-even point LWC 3176 prints/year 74.3 h Break-even point Woodfree uncoated prints/ year 234 h Typical office worker Printer Toner Paper Electricity Total Cost per hour

21 Table 8 shows that at the break-even points for the two printing alternatives. CMLCA Label Category irex DR one year use Break-even point 1 use of printer with LWC paper, laser jet, b/w, 3154 prints Break-even point 2 use of printer with woodfree paper, laser jet, b/w, 5070 prints Unit [C1] Land use competition ,38 120,46 m2a [C3] Eutrophication potential ,0224 0,0523 kg PO4-Eq [C5] Resources depletion (abiotic) ,259 0,366 kg antimony-eq [C14] Acidification potential (average European) ,158 0,240 kg SO2-Eq [C17] Photochemical oxidation (summer smog) , ,0128 kg ethylene-eq [C29] Terrestrial ecotoxicity ,300 0,486 kg 1,4-DCB-Eq [C30] Ionising radiation 1.18E-07 2,96E-07 3,42E-07 DALYs [C34] Marine aquatic ecotoxicity 3.15E E E+04 kg 1,4-DCB-Eq [C38] Freshwater aquatic ecotoxicity ,775 6,479 kg 1,4-DCB-Eq [C46] Stratospheric ozone depletion 7.78E-06 2,64E-06 4,35E-06 kg CFC-11-Eq [C50] Human toxicity ,407 23,703 kg 1,4-DCB-Eq [C56] Climate change GWP 100a (biogene kg CO2-Eq corrected) Note: the values in this table are normalized to the break even point for the climate change impact category. Results for the printing alternatives may thus only be compared to the results for the use of the irex in the first column and not amongst each other. The results for impact categories like land use competition, eutrophication and terrestrial ecotoxicity plead in favor of the use of a Digital Reader. For other categories like photochemical oxidation and aquatic ecotoxicity, the use of a Digital Reader still shows a higher environmental impact. Table 8: Impacts of irex DR compared to impacts at the two break-even points CMLCA Label Category irex DR one year use Break-even point 1 use of printer with LWC paper, laser jet, b/w, 3154 prints Break-even point 2 use of printer with woodfree paper, laser jet, b/w, 5070 prints Unit [C1] Land use competition ,38 120,46 m2a [C3] Eutrophication potential ,0224 0,0523 kg PO4-Eq [C5] Resources depletion (abiotic) ,259 0,366 kg antimony-eq [C14] Acidification potential (average European) ,158 0,240 kg SO2-Eq [C17] Photochemical oxidation (summer smog) , ,0128 kg ethylene-eq [C29] Terrestrial ecotoxicity ,300 0,486 kg 1,4-DCB-Eq [C30] Ionising radiation 1.18E-07 2,96E-07 3,42E-07 DALYs [C34] Marine aquatic ecotoxicity 3.15E E E+04 kg 1,4-DCB-Eq [C38] Freshwater aquatic ecotoxicity ,775 6,479 kg 1,4-DCB-Eq [C46] Stratospheric ozone depletion 7.78E-06 2,64E-06 4,35E-06 kg CFC-11-Eq [C50] Human toxicity ,407 23,703 kg 1,4-DCB-Eq [C56] Climate change GWP 100a (biogene kg CO2-Eq corrected) Note: the values in this table are normalized to the break even point for the climate change impact category. Results for the printing alternatives may thus only be compared to the results for the use of the irex in the first column and not amongst each other. The fact that the irex DR scores higher on some of the categories at the break-even points makes it interesting to compute the impacts at 10,000 prints per office worker per year. This is considered the average amount of paper printed by a typical office worker. Table 9 shows the comparison; using an irex scores better on all impact categories than printing 10,000 pages per year. 21

22 Table 9: Impacts of irex DR compared to impacts at 10,000 prints per year. Label Category irex DR one year use 10,000 prints woodfree paper, laser jet, b/w, print Unit [C1] Land use competition m2a [C3] Eutrophication potential kg PO4-Eq [C5] Resources depletion (abiotic) kg antimony-eq [C14] Acidification potential (average European) kg SO2-Eq [C17] Photochemical oxidation (summer smog) kg ethylene-eq [C29] Terrestrial ecotoxicity kg 1,4-DCB-Eq [C30] Ionising radiation 1.18E-7 6.8E-7 DALYs [C34] Marine aquatic ecotoxicity 3.15E4 4.82E4 kg 1,4-DCB-Eq [C38] Freshwater aquatic ecotoxicity kg 1,4-DCB-Eq [C46] Stratospheric ozone depletion 7.78E E-6 kg CFC-11-Eq [C50] Human toxicity kg 1,4-DCB-Eq [C56] Climate change GWP 100a (biogene corrected) kg CO2-Eq 22

23 5. Evaluation & Interpretation In Chapter 2, two contribution analyses where announced. These were conducted to test the assumptions made in the construction of the inventory. The effects of the assumptions on the inclusion of packaging materials will be discussed first. Secondly, the contributions of the defined e-paper screen, including the Wacom board are treated. Subsequently, other assumptions will be summarized and the overall credibility of the outcomes will be discussed. 5.1 Packaging Materials To test what effect the estimations on the use of packaging for components and commercial delivery have on the results of this study, which were presented in the preceding chapter, contribution analyses for the production, transport and disposal of the packaging materials were conducted. This analysis indicates that under the standard assumptions these life cycle steps are responsible for 0.51 kg CO 2 -equivalent of the total of 17 kg CO 2 -equivalent, thus for only 3% of the total impact on climate change of the Digital Reader. When the amount of packaging used, transported and disposed is doubled, the total climate impact only changes into 17.2 kg CO 2 -equivalent. These two findings indicate that packaging is only responsible for a minor part of the impacts on climate change and that adjusting assumptions on the use of packaging are not crucial to the validity of this study. 5.2 E-paper Screen The second issue of concern is the LCD module as it was manually defined to represent the electronic ink screen; one of the most typical components of the Digital Reader. A contribution analysis shows that the module is responsible for 33% of the total climate change impact of the whole Digital Reader. During the LCD module assembly the use of many specialty chemicals generate a variety of environmental emissions. 49% of this 5.65 kg CO 2 -equivalent is due to the emission of sulphur-hexa-fluoride (a very potent greenhouse gas). Although the e-ink screen is probably the most complex as well as the largest and heaviest component used in the Digital Reader (excluding the plastics), it remains troublesome to assign such a large impact contribution to a component with a more or less estimated composition and production process. Until more research has been done on the specifics of the e-ink screen this remains the best possible assumption. 5.3 Summary of Assumptions Various assumptions have been made throughout this study which have not been subject to extensive evaluating analyses. The most important ones are summarized and presented here once more as a marginal note, to emphasise the contextual limitations to the results of this study, as those are presented in Chapter 4. First of all a few uncertainties originate from the unclear definition or incomplete reporting in the Ecoinvent database: - As discussed in Paragraph It remains unclear whether the database inputs for toner and energy use during printing are based on double- or single sided printing. It is assumed the values are based on an average between these. - Due to the definition of the processes for electronics disposal by Ecoinvent, it is impossible to find out whether the transport of products to the disposal facility is 23