Life Cycle Assessment Of A Smartphone - Atlantis Press

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4th International Conference on ICT for Sustainability (ICT4S 2016)Life Cycle Assessment of a SmartphoneMine Ercan, Jens Malmodin, Pernilla BergmarkEmma Kimfalk (former employee), Ellinor NilssonEricsson Research, Ericsson ABStockholm, Swedenmine.ercan@ericsson.comSony Mobile CommunicationsCorporate Sustainability OfficeLund, Swedenellinor.nilsson@sonymobile.comAbstract— It is of interest to understand the life cyclecontribution from the use of smartphones including theirnetwork usage, as well as to gain knowledge regarding theimpact of the smartphone as a device to provide input fornetwork studies. This cradle-to- grave study is based on lifecycle assessment (LCA) methodology as outlined by theISO14040 series and the supplementing ICT specific LCAstandard from ETSI/ITU. The paper provides detailsregarding data collection, assumptions, methods and results.Furthermore, sensitivity analysis results for selectedparameters are presented, including variations due to differentsecondary data sets. This study calculates the Global WarmingPotential (GWP) for the assessed smartphone (a Sony MobileZ5) including accessories) to 57 kg CO2e for an assumedoperating life time of 3 years, excluding the network usage.Results are also presented for other impact categories and asyearly figures. In addition, the distribution of impacts betweenlife cycle stages is provided for the assessed impact categories.Integrated circuit (IC) production is identified as a majorcontributor to the overall impacts followed by the productionof the display. For GWP specifically, overall results are alsoprovided including the network usagerepresent all environmental impacts and thus broader studiesare needed to gain a comprehensive understanding of theenvironmental impacts of mobile phones, especially toxicityimpacts (which on the other hand show large uncertainties asthis study shows). Suckling and Lee [5] also note that themajority of studies are published by manufacturers and noteseveral circumstances that make results hard to compare. Theauthors of this study agree with this view and make everyeffort to present results for a broad range of impactcategories and a sufficient level of detail, in order for theresults to be comprehensive and interpretable. However, dueto its importance, and considered as the most importantimpact category by the ETSI/ITU standard, GWP is given agreater focus than other impact categories.The paper outline is as follows: firstly the methodology ispresented in section II, then the goal and scope in section IIIand the life cycle inventory (LCI) in section IV. In section Vthe results of the life cycle impact assessment (LCIA) aregiven followed by interpretation and normalization combinedwith a sensitivity analysis in section VI. The paper concludeswith a discussion in section VII and conclusions are finallydrawn in section VIII.Index Terms—ICT, GHG emissions, LCA, life cycleassessment, smartphone, telecommunicationII. METHODOLOGYI. INTRODUCTIONThis study is based on LCA methodology as outlined byISO and covers a multiple number of impact categories ofthe smartphone and its associated network usage, fromcradle-to-grave. Furthermore it considers the joint standardfor LCA of ICT goods, networks and services developed byEuropean Telecommunications Standard Institute (ETSI) [8]and International Telecommunication Union (ITU) [9].In line with Ercan [6] and Moberg et al. [7], who suggestto prioritize primary data collection efforts on keycomponents (primarily integrated circuits) and energy useduring production and use stage, this study has used primarydata for production processes to the extent possible andcalculated results for three different usage scenarios as actualusage varies between users. Further data details are given insection IV.GaBi software [10] has been used as the modeling toolfor this study and as a source for secondary data, includingthe data sets from Eco-invent as well as GaBi s own data.It is commonly known that the use of smartphones inmobile communication networks is rapidly growingworldwide and thereby their contribution to theenvironmental and economic impacts of telecommunicationnetworks. Although our research forecasts that theInformation and Communication Technology (ICT) sector toremain within 2% of the total global greenhouse gas (GHG)emissions until 2020 [1], such development indicates anincreased need for information regarding the environmentaleffects of smartphones. Recently, initiatives to reduce theenergy consumption and the GHG emissions ofcommunication networks have gained momentum. There isalso an increasing interest in resource efficiency and thecircular economy [2], and in eco-rating of mobile phones [34]. Consequently life cycle impact assessments are neededfor smartphones to build a comprehensive understanding oftheir potential environmental impacts.In their literature review of mobile phone LCAs [5],Suckling and Lee note that most studies that assess the lifecycle impacts of mobile phones (including smartphones butalso feature phones), report impact only in terms of GWP orenergy [6]. As noted by Moberg et al. [7], the globalwarming potential (GWP) category alone cannot be used to 2016. The authors - Published by Atlantis PressIII. SCOPEA. Product systemThe study is targeting two new high-end smartphones bySony (models Z3 and Z5) with accessories (see Fig. 1). It124

includes the smartphone device itself as well as, for GWP,the associated life cycle impact from the network usage. Themain difference between Z3 and Z5 models is the totalintegrated (IC) chip area, where Z5 has a larger area (9.5cm2) compared to Z3 (7.5 cm2). The touch-screens have thesame size, and most other parts and components are thesame; so the difference in weight is only a few grams.A. The smartphone (Z3)B. HeadsetC. USB-cableD. ChargerE. DocumentationX. Delivery packagingY. Transport packagingSee section IV for specifications of the usage scenario.For GWP, results are also presented per year andincluding the life cycle impact from the associated networkusage.C. System boundariesAll life cycle stages and processes are included inaccordance with the joint ETSI/ITU LCA standard ([8]-[9])except reconditioning of mobile phones for reuse. For adetailed overview of processes refer to Figure 7 of thestandard. Two cut-offs were made: Impact from third partyoverhead activities (e.g. marketing services) were notincluded in the supporting activities. Impact from materialsbeyond the around 30 most contributing materials accordingto the previous experience of the authors were not accountedfor.D. Impact indicatorsBased on recommendations from the InternationalReference Life Cycle Data System (ILCD) [11], theenvironmental life cycle impact assessment (ELCIA)indicators are chosen as presented in Table I together withthe adopted impact assessment methods.152 g (see details below)16 g21 g50 g48 g74 g (not included in picture)66 g (not included in picture)TABLE I. IMPACT INDICATORSELCIA indicators asrecommended by ILCDUnitReferenceGlobal Warming Potential (GWP)CO2-eq.IPCC, 100 yearsOzone Depletion Potential (ODP)CFC-11-eq.WMO OSmodel, ReCiPeHuman Toxicity Cancer potentialeffects (HumToxCan)Human Toxicity non-Cancerpotential effects (HumTox)Particulate Matter (2.5 µm) (PM)Photo-Oxidant Creation Potential(POCP)NMVOC-eq. Acidification Potential (AP)1.2.3.4.5.6.7.8.Frame/backsideMetal sheetsDisplayBatteryPBAs/ICsFlex-filmsCamerasOther componentsEutrophication Potential (freshwater) (EP fresh)Eutrophication Potential (terrestrial)(EP terr)Eco-system Toxicity potential effects(EcoTox)27 g (mainly plastics)15 g21 g (facing down, not visible)48 g13 g6.5 g1.5 g11 gMole of H eq.Mole of N-eq.g P-eq.CTUe3Accumulatedexceedance modelEUTREND model,ReCiPeAccumulatedexceedance modelUSEtoxFreshwater consumption (Water)mSwiss EcoscarcityAbiotic Depletion Potential (ADP)Sb-eq.CML (reservebased)Fig. 1. Smartphone composition and accessoriesIV. LIFE CYCLE INVENTORYEmbodied impacts from software developed outsideSony (apps in general) are not included in the scope,however software impacts are considered for the use stage asdata center services are included in network usage.A. Emission factorsGeneric GaBi models have been used for the energy andfuel models. The emission factors include the supply chainfor the energy and fuel production, as it may have significantenvironmental impacts on the total results.For primary data, the production related electricity mixesare based on the locations of the suppliers. For secondaryGaBi data, electricity mixes are based on locations embodiedB. Functional unitThe functional unit is set to life time usage (3 years) ofthe smartphone device and its accessories for arepresentative usage scenario.125

in the data. For ICs and ASICs specifically, supplierinformation was used corresponding to an emission factorclose to world average (around 0,6 kg/kWh).For use stage, a world average emission factor wasapplied as the assessed products are intended for a globalmarket.As reflected in Section V and VI energy models werefirst modelled based on Ecoinvent data, then also with GaBidata. The Ecoinvent energy models include buildingconstruction and materials (including metals) within theirsystem boundaries.directly representing an unknown mix of virgin and recycledmaterials.Li-battery recycling (e.g. cobalt) has not been includedbut the impact will be minor and mainly add to ADP.C. Production1) Parts productionProduction process data are based on primary data collectedfrom Sony’s suppliers through a questionnaire where inputwas provided as annual figures for 2014 representing energyconsumption, generated waste, ancillary products, emissionsto soil, air and water and production related transportations.With the exception of ICs and ASICs, supplier supportactivities are excluded. Data were obtained from directsuppliers to Sony but not from the sub-suppliers. Table IIbelow shows primary and secondary data sources for partsproduction. Where primary input data were insufficient orunavailable, data from previous studies or secondary datawere used.B. Raw Materials Acquisition1) Smartphone raw materialsPrimary materials data were provided by Sony per partpresented in Fig. 1, and for selected components, such asprinted board assemblies (PBAs). The component level datawere used to model other similar components. For example,materials for all Application Specific Integrated Circuits(ASICs) were based on materials for one ASICs scaled up toreflect the overall ASIC weight. The acquisition processesfor these raw materials were modeled in GaBi based onsecondary data. Transportations related to the raw materialacquisition stage were included in these data to an unknownextend and it was not possible to extract transportationdetails from the available data set. Electricity mixes arebased on location and embodied in the GaBi data.2) Packaging materialsAmounts of packaging materials for parts and finaldelivery have been estimated based on Ericsson conditionsand factors have been applied that represent the packagingmaterial weight in relation to the part or device weight. Someparts such as the IC and PBA require more packaging as theyare more fragile and hence have a higher packaging factor.Packaging materials include steel, polyurethane foam,polyurethane wood, plywood and cardboard and theiracquisition processes are based on secondary GaBi data.3) Virgin and recycled materialsThe raw material stage takes into consideration the virginand recycled inputs for some selected materials; copper,gold, silver and aluminium based on world marketconditions. The virgin material input varies between 30 to 80percent based on global recycling rates [12].ETSI/ITU recommends a 50/50 approach to be used. Thisapproach seeks to distribute the impacts from primarymaterial production and waste treatment to the first and lastlife cycle in equal amounts, however without consideringmaterial loss at design or end-of-life treatment. Due to lackof details in the used data base, the 50/50 approach could notbe applied consistently. For this reason this study developedan own approach by applying the 50/50 approach for twodifferent scenarios for smartphone recycling (19% or 83%depending on modelling of informal recycling) based on [13]and a world average rate of recycled gold (28% based onindustry data from CPM group) For other metals, the GaBimodels did not distinguish between virgin and recycledmaterials. For these metals the GaBi models were appliedTABLE II: PARTS PRODUCTION DATA TYPES FOR THE SMARTPHONEPrimary supplier dataChargerHeadsetUSBPackaging boxSony assemblyKey PanelTouch and DisplayMicrophoneRF SwitchSecondary dataVibratorCameraBatteryFCBSpeakerAntennaPCBRF SwitchASICS and IC (partly)ASICS and IC (ICTspecific, see section C 2)Connectors (GaBi)Inductor Chip (GaBi)Resistors (GaBi)Capacitors (GaBi)The collected facility data were allocated based onSony s share of overall production and surface area (ASICS,IC and PBA) or weight (all others).Due to confidentiality, production related input dataincluding location of facilities have restricted availability butthe resulting potential environmental impacts are presentedin section V.2) Integrated circuit (IC) productionThe production of ICs is known as a resource intensiveproduction process with substantial energy and resource usewith among the highest environmental impacts per mass unitthat exist today for mass produced products. The model usedin this study considers yield and covers all main productionprocesses including production of silicon wafer, chip onwafer (“wafer-fab”) and the IC packaging (encapsulation).Also of main importance and included for the wafer fab, andto some extent also for other processes, are production of allspecial gases, chemicals and materials; emissions of gaseswith high GWP; supporting activities; and; the building ofthe factory itself and the production of process equipment

Abstract— It is of interest to understand the life cycle contribution from the use of smartphonesare needed to gain a comprehensive understanding of the including their network usage, as well as to gain knowledge regarding the impact of the smartphone as a device to provide input for network studies. This -to- grave cradlestudy is based on life