ArticlePDF Available

Reducing the carbon footprint of ICT products through material efficiency strategies: A life cycle analysis of smartphones

Authors:

Abstract and Figures

With the support of a life cycle assessment model, this study estimates the carbon footprint (CF) of smartphones and life cycle costs (LCC) for consumers in scenarios where different material efficiency strategies are implemented in Europe. Results show that a major contribution to the CF of smartphones is due to extraction and processing of materials and following manufacturing of parts: 10.7 kg CO2,eq/year, when assuming a biennial replacement cycle. Printed wiring board, display assembly, and integrated circuits make 75% of the impacts from materials. The CF is increased by assembly (+2.7 kg CO2,eq/year), distribution (+1.9 kg CO2,eq/year), and recharging of the device (+1.9 kg CO2,eq/year) and decreased by the end of life recycling (−0.8 kg CO2,eq/year). However, the CF of smartphones can dramatically increase when the energy consumed in communication services is counted (+26.4 kg CO2,eq/year). LCC can vary significantly (235–622 EUR/year). The service contract can in particular be a decisive cost factor (up to 61–85% of the LCC). It was calculated that the 1:1 displacement of new smartphones by used devices could decrease the CF by 52–79% (excluding communication services) and the LCC by 5–16%. An extension of the replacement cycle from 2 to 3 years could decrease the CF by 23–30% and the LCC by 4–10%, depending on whether repair operations are required. Measures for implementing such material efficiency strategies are presented and results can help inform decision‐makers about how to reduce impacts associated with smartphones.
This content is subject to copyright. Terms and conditions apply.
DOI: 10.1111/jiec.13119
RESEARCH AND ANALYSIS
Reducing the carbon footprint of ICT products through
material efficiency strategies
A life cycle analysis of smartphones
Mauro Cordella1,2Felice Alfieri1Javier Sanfelix3
1European Commission, Joint Research
Centre, Seville, Spain
2TECNALIA, Basque Research and Technology
Alliance (BRTA),Derio, Spain
3European Commission, Directorate General
for Research and Innovation, Brussels, Belgium
Correspondence
Mauro Cordella, TECNALIA, Basque Research
and TechnologyAlliance (BRTA),Astondo
Bidea, Edificio 700, 48160 Derio, Spain.
Email: mauro.cordella@tecnalia.com
Editor Managing Review: Niko Heeren.
Funding information
European Commission, Grant/Award
Number: Administrative Agree-
ment N. 070201/2015/SI2.719458 (signed
between DG ENV and DG JRC)
Abstract
With the support of a life cycle assessment model, this study estimates the carbon foot-
print (CF) of smartphones and life cycle costs (LCC) for consumers in scenarios where
different material efficiency strategies are implemented in Europe. Results show that
a major contribution to the CF of smartphones is due to extraction and processing of
materials and following manufacturing of parts: 10.7 kg CO2,eq/year, when assuming a
biennial replacement cycle. Printed wiring board, display assembly, and integrated cir-
cuits make 75% of the impacts from materials. The CF is increased by assembly (+2.7 kg
CO2,eq/year), distribution (+1.9 kg CO2,eq/year), and recharging of the device (+1.9 kg
CO2,eq/year) and decreased by the end of life recycling (0.8 kg CO2,eq/year). However,
the CF of smartphones can dramatically increase when the energy consumed in com-
munication services is counted (+26.4 kg CO2,eq/year). LCC can vary significantly (235–
622 EUR/year). The service contract can in particular be a decisive cost factor (up to
61–85% of the LCC). It was calculated that the 1:1 displacement of new smartphones
by used devices could decrease the CF by 52–79% (excluding communication services)
and the LCC by 5–16%. An extension of the replacement cycle from 2 to 3 years could
decrease the CF by 23–30% and the LCC by 4–10%, depending on whether repair oper-
ations are required. Measures for implementing such material efficiency strategies are
presented and results can help inform decision-makers about how to reduce impacts
associated with smartphones.
KEYWORDS
climate change, industrial ecology, life cycle assessment (LCA), life cycle costs (LCC), material
efficiency, smartphone
1INTRODUCTION
Although the climate change threat due to anthropogenic emissions of greenhouse gases (GHG) was raised by the scientific community 30 years
ago (IPCC, 1992), it has been only partially reflected in effective interventions under the frameworks of the Kyoto Protocol (United Nations, 1997)
and the Paris Agreement (United Nations, 2015).
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided
the original work is properly cited.
© 2021 European Commission, Joint Research Centre (JRC-Seville). Journal of Industrial Ecology published by Wiley PeriodicalsLLC on behalf of Yale University
448 wileyonlinelibrary.com/journal/jiec Journal of Industrial Ecology 2021;25:448–464.
CORDELLA ET AL.449
FIGURE 1 Material efficiency aspects in the life cycle of a product (Cordella et al., 2020a)
The European Commission has reinforced its commitment to tackle environmental challenges through the “European Green Deal” (European
Commission, 2019a), which includes measures on energy efficiency and circular economy performance of the information and communication tech-
nologies (ICT) sector.
The contribution of the ICT sector to the global GHG emissions was about 1.4% in 2007 and could exceed 14% in 2040. In particular, the contri-
bution from smartphones is increasing so rapidly that it could soon become greater than desktops, laptops, and displays. The main reasons for this
growth are the high market penetration of smartphones and their short replacement cycles (2 years on average) (Belkhir & Elmeligi, 2018).
In the European Union (EU), ICT products fall within the scope of Ecodesign Directive (European Union, 2009) and Energy Label Regulation
(European Union, 2017). These set out a regulatory framework for improving the energy efficiency of energy-related products (European Commis-
sion, 2016), with a current shift toward the more systematic consideration of material efficiency aspects (European Commission, 2019b). Material
efficiency could be defined as the ratio between the performance of a system and the input of materials required (Cordella et al., 2020a). As shown
in Figure 1, material efficiency can be improved along the life cycle of products by strategies that aim to minimize material consumption, waste
production, and their environmental impacts (Allwood et al., 2011; Huysman et al., 2015). In practice, this could be achieved by designing products
that are more durable and easier to repair, reuse, or recycle (European Commission, 2015).
The relevance of material efficiency strategies for mitigating climate change impacts depends on the relative impacts associated with each life
cycle stage of a product (Iraldo et al., 2017; Sanfelix et al., 2019; Tecchio et al., 2016), which can be quantified through life cycle assessment (LCA)
(ISO, 2006a;ISO,2006b).
The analysis of LCA studies can provide indications about the environmental impacts of smartphones (Cordella & Hidalgo, 2016). For exam-
ple, Andrae (2016), Ercan et al. (2016), and Clément et al. (2020) analyzed the Bill of Materials (BoM) of specific devices and their life cycle GHG
450 CORDELLA ET AL.
emissions (hereafter referred to as carbon footprint, CF). Manhart et al. (2016) analyzed resource efficiency aspects in the ICT sector, reporting the
CF of different devices. CF results are also shared by some manufacturers (e.g., Apple (2019); Huawei (2019)).
In terms of scenarios of use, Ercan et al. (2016) analyzed the effects of different use intensities of smartphones. An assessment of CF mitigation
effects of remanufacturing, reuse, and recycling is provided in Andrae (2016), while repair and refurbishment scenarios were assessed by Proske
et al. (2016). A comparative assessment of end of life (EoL) repurposing (vs. refurbishment) was carried out by Zink et al. (2014) . Furthermore,
Suckling and Lee (2015) provided a comparison of the CF associated with the EoL collection of old phones for reuse, remanufacturing, and recycling.
Economic considerations for EoL scenarios can also be found in the literature (Clift & Wright, 2000; Geyer & Doctori Blass, 2010; Gurita et al.,
2018). Furthermore, recent studies go beyondattributional LCA approaches by discussing rebound effects that could happen at macro-scale (Makov
& Font Vivanco, 2018; Makov et al., 2018;Zink&Geyer,2017; Zink et al., 2014).
This study aims to build upon the existing LCA literature for smartphones and expand it by providing a broad and critical analysis of material effi-
ciency strategies and their effect on CF and life cycle costs (LCC) for consumers. Measures are also identified to assist decision-makers in mitigating
impacts of smartphones in a cost-effective way.
2MATERIALS AND METHODS
2.1 Life cycle analysis of material efficiency strategies for smartphones
An attributional LCA was carried out for the analysis of material efficiency strategies. The aim was not to compare specific devices but to produce
general considerations for the EU. A number of scenarios were assessed that involve different technological and behavioral practices:
I. Baseline scenario (purchase, use and disposal of new smartphones);
II. Extended use scenarios with/without repair operations;
III. Scenarios involving the purchase of remanufactured or second-hand devices (both referred to also as “used devices” in this paper)1;
IV. Scenarios involving lean design concepts.
Ta b l e 1and the following sections provide an overview of analyzed scenarios and modeling assumptions.
2.1.1 Reference indicators
TheCF,expressedasCO
2,eq, was calculated based on the 100-year global warming potentials (GWP) of GHG emissions (IPCC, 2013). Although GWP
correlates to a number of environmental indicators (Askham et al., 2012; Huijbregts et al., 2006), a broader metric (covering impact categories such
as resource scarcity, biodiversity, and toxicity) would allow for a more comprehensive sustainability assessment (Moberg et al., 2014). Additional
environmental considerations are addressed qualitatively while discussing results. It is anticipated that the use of broader metric for the assessment
of smartphones (Ercan et al., 2016; Moberg et al., 2014; Proske et al., 2016) confirmed the importance played by manufacturing processes and
extraction of materials (e.g., cobalt, copper, gold, silver).
The quantitative assessment also included economic considerations about the LCC for consumers (COWI & VHK, 2011), expressed as EUR 2019
and calculated according to Equation (1). The formula was obtained by considering the present value factor equal to 1 (Boyano Larriba et al., 2017).
LCC =PP +
N
1
OE +MRC +ELC,(1)
where:
LCC: life cycle costs for end users;
PP: purchase price;
OE: annual operating expenses for each year of use;
N: reference time in years;
MRC: maintenance and repair costs (when applicable);
ELC: end of life costs/benefits.
1Definitions used for lifetime extension processes (value-retention processes) vary widely (IRP, 2018). In this work, remanufacturing and refurbishment are used interchangeably to indicate the
“modification of an object that is a waste or a product to increase or restore its performance and/or functionality or to meet applicable technical standards or regulatory requirements, with the
result of making a fully functional product to be used for a purpose that is at least the one that was originally intended.” However,while remanufacturing is typically used for an industrial process to
make “as-new”products that carry a legal warranty, refurbishment requires operations that exceed repair but are less structured, industrialized and quality focused than remanufacturing (e.g., data
wiping and upgrade, repair for functionality,aesthetic touch-ups). Refurbishment is defined as “comprehensive” when happening within industrial or factory settings (IRP, 2018).
CORDELLA ET AL.451
TAB L E 1 Scenarios considered for the assessment of material efficiency aspects in the life cycle of smartphones
Scenario Key assumptions for the CF assessment Additional consideration for the LCC assessment
Baseline (BL) Replacement cycle: smartphones are replaced with a new
device (the same model) every 2 years; new devices are
bought and allocated to cover the reference lifetime (i.e.,
2.25 units for a period of 4.5 years).
EOL: the old product is kept unused at home.
Other system aspects: impact associated to data consumption
during the use phase are not considered. For sensitivity
analysis, BL+also consider:
- Impact associated to the usage of communication networks
during the use-phase;
- End-of-Life recycling with pre-treatment for battery
recovery.
Costs associated to the mobile contract service are included.
For sensitivity analysis, the following scenarios are
considered:
- BL, where an average product is considered;
- BL-HE, where a high-end product is considered;
- BL-LE, where a low-end product is considered.
Extended use (EXT) Replacement cycle: compared to BL, replacement cycle
increased to 3 (EXT1) and 4 years (EXT2), which results in
the need of less devices along the reference lifetime (i.e.,
1.5 and 1.125 units, respectively).
Other assumptions: as BL.
The following scenarios are considered:
- EXT1 and EXT2: as BL, with replacement cycle increased to 3
and 4 years, respectively;
- EXT1-HE and EXT2-HE: as BL-HE, with replacement cycle
increased to 3 and 4 years, respectively.
Battery change (BC) Replacement cycle: compared to EXT1 and EXT2, replacement
cycle is the same (i.e., 3 years for BC1 and 4 years for BC2)
with the change of the battery.
Other assumptions: as EXT1 and EXT2.
The following scenarios are considered:
- BC1a: as EXT1, with change of the battery made by the user;
- BC1b: as EXT1, with change of the battery made by a
professional repairer;
- BC2: as EXT2, with change of the battery made by the user.
Display change (DC) Replacement cycle: compared to EXT1 and EXT2, replacement
cycle is the same (i.e., 3 years for DC1 and 4 years for DC2)
with the repair (change) of the display.
Other assumptions: as EXT1 and EXT2.
The following scenarios are considered:
- DC1a: as EXT1, with repair of the display by the user;
- DC1b: as EXT1, with repair of the display by a professional
repairer;
- DC2: as EXT2, with repair of the display by the user.
Battery change +
display change
(BC-DC)
Replacement cycle: compared to EXT1 and EXT2, replacement
cycle is the same (i.e., 3 years for BC-DC1 and 4 years for
BC-DC2) with battery change and the repair (change) of
the display.
Other assumptions: as EXT1 and EXT2.
Not assessed directly.
Remanufacture (RM) Replacement cycle: remanufactured smartphones bought by
users every 2 years, to cover the reference lifetime (i.e.,
2.25 units for a period of 4.5 years).
Remanufactured device impacts: due to battery change, display
change, energy for manufacturing and transport.
EOL: the old product is kept unused at home.
As BL, with purchase price of the product calculated as the
cost of battery change and display repair.
Reuse (RU) Replacement cycle: reused smartphones bought by users
every 2 years, to cover the reference lifetime (i.e., 2.25
units for a period of 4.5 years).
Reused device impacts: due to battery change, display change,
and transport.
EOL: the old product is kept unused at home.
As BL, with purchase price of the product calculated as one
third of the original price and a margin of 40%.
Lean design (LD) Device manufacturing impacts: reduction of materials used for
housing: 10% by weight (LD1), 20% by weight (LD2),
30% by weight (LD3).
Other assumptions:asBL.
Not assessed directly.
2.1.2 Functional unit and reference flow
Smartphones are multi-functional devices that provide different types and levels of performance. The assessment of specific devices should refer
to a functional unit (FU) that covers both quantitative and qualitative aspects (ETSI, 2019), and only products with similar characteristics should be
compared, which is beyond the scope of this study.
The FU considered in this study is the use of smartphones by a European consumer during a reference time of 4.5 years. This was chosen, based
on data from Prakash et al. (2015), as a proxy for the potential time during which smartphones can be used. This is comparable with average lifespan
452 CORDELLA ET AL.
data for mobile phones reported by Bakker et al. (2014) (4.5 years in 2005, Dutch data) and Makov et al. (2018) (4.5 and 5.6 years for two brands in
2015–2016, US data), which cover the first use cycle and possible subsequent use cycles of the product before the EoL disposal by the final owner.
The reference flow is the number of smartphone devices purchased, used, and disposed by the consumer during this period. The reference
flow is determined by the replacement cycle of smartphones (see Section 2.2.2): for a replacement cycle of Xyears, the reference flow is equal to
4.5 divided by X.
2.1.3 Assessed scenarios and system boundaries
The scenarios assessed in this study are reported in Table 1. For each scenario, the system boundaries cover the cradle-to-grave analysis of a generic,
virtual product.
As a baseline (BL), the following stages are considered:
1. Production of parts (extraction, processing and transportation of materials, manufacturing of parts);
2. Smartphone manufacturing (transportation of parts, device assembly);
3. Distribution and purchase (transportation of smartphones to points of sale);
4. Use (energy for battery recharging);
5. EoL replacement (old unused device being kept at home).
Additional scenarios integrate the following aspects: system impacts associated with communication services and EoL recycling (BL+), extended
use (EXT), battery change (BC), repair and change of the display (DC), remanufacture (RM), reuse (RU), lean design (LD). Services and material goods
necessary to support the business (e.g., research and development, marketing) are excluded from the assessment.
2.2 Carbon footprint modeling
LCA studies published from 2014 onward were screened to identify relevant sources of data for the analysis (Cordella& Hidalgo, 2016). The CF was
calculated based on such information and life cycle inventory (LCI) datasets (cut-off system models) from Ecoinvent 3.5 (Wernet et al., 2016), with
proxies used in the presence of data gaps. Assumptions made to handle existing data limitations were discussed with expertsin the sector (Cordella
et al., 2020b), and results compared with those of other studies (see Table 2). The GHG emission factors used for the assessment are provided in
Supporting Information S1.
2.2.1 Production of parts and manufacturing of the device
An average smartphone was considered to have a displaysize of 75.53 cm2and a weight of about 160 g, including 39 g for the battery and excluding
accessories and packaging (Manhart et al., 2016). Additional materials are necessary for packaging (cardboard and plastic materials), documenta-
tion, and accessories such as head set, USB cable, charger. The BoM of the virtual product is reported in Supporting Information S1.
Scenarios RM and RU, which involvethe purchase of remanufactured or second-hand devices, include a change of battery and display. The weight
of materials used for the housing and display of smartphones were proportionally decreased in the LD scenarios, without investigating how this can
affect other geometrical design characteristics (e.g., display size).
The assembly of one unit of smartphones was considered to happen in China and require 4.698 kWh (Proske et al., 2016). The same energy
consumption value (worst-case assumption) was considered for the remanufacturing of the device in industrial settings. However, when fewer
refurbishment operations are needed (e.g., clean-up and software update), the energy intensity of the remanufacturing process could be lower, for
example, 0.033 kWh per device (Skerlos et al., 2003). Section 3.1.4 shows a sensitivity analysis on this parameter, which provides an uncertainty
range for RM.
Regarding the transport of parts to the assembling factory, it was considered that housing and packaging materials are transported by lorry for
1000 km and 100 km, respectively, while other components (mostly electronics) are transported for 1000 km by flight and 100 km by lorry. Such
assumptions aimed to reflect the geographical availability of parts and materials and the ease/difficulty of procuring them.
2.2.2 Distribution and use
The following means of transport were considered for the distribution of smartphones: 8000 km by flight (distance between Beijing and Brussels)
and 600 km by heavy truck (transport distance proxy within Europe).
CORDELLA ET AL.453
TAB L E 2 Carbon footprints and key parameters from LCA studies on smartphones
Parametera) BL (this study)
Andrae
(2016)
Ercan et al.
(2016)
Proske et al.
(2016) Apple (2019)f) Huawei (2019)g)
CF, over the reference lifetime (kg CO2,eq )b) 77.2 39.2 56.7 43.9 45.079.0
(average: 61.2)
50.084.5
(average: 61.9)
CF contribution due to EOL recycling
(kg CO2,eq)c)
Not considered 0.4 0.3 1.0 0.2 0.1
Reference lifetime (years) 4.5 2 3 3 3 2
Replacement cycle (years) 2 2 3 3 3 2
Reference flow (smartphone units) 2.25 1 1 1 1 1
Weight of one device (g)d) 160 223 152 168 112208
(average: 159)
142232
(average: 163)
CF contribution due to the manufacturing of
one device (kg CO2,eq)e)
26.7 38.3 49.8 36.0 24.8–63.2
(average: 45.3)
41.0–70.4
(average: 51.4)
CF, adjusted to BL conditions for thisstudy
(kg CO2,eq)
- Over 4.5 years 77.2 87 123 97 66.8117.3
(average: 90.9)
112.3189.8
(average: 139.0)
- Normalized to 1 year of use 17.2 19.4 27.3 21.5 14.926.1
(average: 20.2)
25.042.2
(average: 30.9)
- Normalized to BL 100% 113% 159% 125% 86152%
(average: 117%)
146246%
(average: 180%)
Notes:
a) A full comparison of results is not possible since they depend on modeling assumptions and datasets used in different studies.
b)Communication services excluded.
c)Positive numbers indicate burdens, negative numbers indicate net savings.
d)Accessories and packaging excluded.
e)Including extraction and processing of raw materials, manufacturing of parts and assembling of the device.
f)Based on the analysis of 15 models (additional information reported in the Supporting Information).
g)Based on the analysis of 32 models (additional information reported in the Supporting Information).
The use of smartphones directly implies electricity consumption for the battery recharging cycles. The duration and frequency of recharg-
ing cycles can vary depending on technical characteristics of devices as well as user behavior (Falaki et al., 2010). An electricity consumption of
4.9 kWh/year was calculated by Proske et al. (2016) considering a battery capacity of 2420 mAh, 3.8 V of voltage, 69% of recharge efficiency, and
365 charge cycle per year. According to Andrae (2016), energy consumption is 1.538 times the battery capacity and can be 2–6 kWh/year, which is
similar to the 3–6 kWh/year estimated by Manhart et al. (2016). Ercan et al. (2016) instead quantified that the annual electricity demand of a smart-
phones can range from 2.58 kWh (1 recharge every 3 days) to 7.74 kWh (1 recharge per day). Based on the available information it was assumed
that the average electricity consumption directly associated with the use of smartphones is 4 kWh/year.
Furthermore, it was considered as BL that smartphones are used for 2 years (Belkhir & Elmeligi, 2018; Prakash et al., 2015), before being replaced
with new devices. This does not mean that the device performance is necessarily compromised after 2 years. The decision to replace a smartphone
is often based on perceived functional obsolescence when compared to new models on the market (Makov& Fitzpatrick, 2019; Watson et al., 2017).
The replacement cycle was extended in other scenarios, resulting in the need for fewer device units over the reference time of 4.5 years (see
Section 2.1.2), as indicated in Table 1. In some scenarios, this was associated with a repair operation. Replacements of battery and/or display are
analyzed since these parts are frequently impacted by loss of performance, failures, and breakages (OCU, 2018,2019). Cordella et al. (2020b)
estimated that the likelihood of replacing the display or the battery during the lifespan of a smartphone could be up to 24% and 50%, respectively.
These proxies were used to build an average EU scenario (see Section 3.3).
2.2.3 End of life
Based on the literature (Ellen MacArthur Foundation, 2012; Ercan, 2013; Manhart et al., 2016), it was estimated that about 49% of devices are
kept unused at home once they reach their EoL; 36% find a second use (either as donation or through second-hand markets); 15% are collected and
recycled/remanufactured. As BL, it was assumed that devices are kept unused at home.
454 CORDELLA ET AL.
With respect to recycling, impacts can vary depending on characteristics of product recycling process (Geyer & Doctori Blass, 2010), as well as
on assumptions made and data used. For example, Proske et al. (2016) estimated that the recycling of battery, copper, and other precious materials
from a smartphone of 168 g yields a net saving of 1140 g CO2,eq (calculated as “burdens from impacts” minus “credits from avoided impacts”).
Andrae (2016) instead reported that the recycling of a smartphone of about 220 g result in the emission of 400 g of CO2,eq. A net saving of about
2150 g of CO2,eq would result by taking the full recovery of precious metals into account (calculated based on Manhart et al. (2016)andAndrae
(2016)). Although technologically feasible, a full recovery of precious metals (e.g., magnesium, tungsten, rare earth elements, tantalum) may not be
economically viable (Manhart et al., 2016).
The typical recycling process for smartphones consists of mechanical and manual operations for the separation of materials, including plastics,
and the recovery of batteries, copper, precious metals (gold, silver, platinum), aluminum, and steel (Manhart et al., 2016).
To provide an indication of the potential benefits associated with the recycling of smartphones (Cordella et al., 2020b), the estimate from Proske
et al. (2016) was rescaled to 160 g (device weight considered in this study), and credits were assigned to the recovery of materials and energy from
the housing (display excluded). It was assumed that:
Recycled materials can fully displace primary materials, which is not necessarily the case in real markets (Palazzo et al., 2019), as also discussed
in Section 3.1.3.
Aluminum and steel can be completely recycled at the EoL, and their recycling avoids the production of new materials, while emitting 1.01 and
0.85 g of CO2,eq per gram of aluminum and steel recycled, respectively.
Plastics are incinerated, which avoids 0.094 Wh of electricity and produces 1.04 g of CO2,eq per gram of plastic incinerated.
As a net result, it was estimated that the recycling of a smartphone could lead to the saving of 1640 g of CO2,eq.
2.2.4 Communication services
Beside battery recharging, energy is also needed for the operation of communication services such as mobile networks, fixed access networks (e.g.,
wi-fi), and core networks (e.g., data center and transmission infrastructures). Ercan et al. (2016) estimated that the energy used for operatingmobile,
wireless, and core networks correspond to 28.7 kWh/year for a light user, 33.3 kWh/year for a representative user, and 49 kWh/year for a heavy
user. According to Andrae (2016), the electricity consumption for operating networks and data center infrastructures is 1.16 kWh/GB. Considering
an average consumption of 4 GB per month (Transform Together, 2018), the annual consumption of electricity would be 55.7 kWh. This figure, which
is close to the heavy user estimation by Ercan et al. (2016), was considered in this study,also to reflect the trend toward increased data consumption
(Transform Together, 2018).
2.3 Life cycle cost modeling
2.3.1 Purchase price for new products and operating costs
A business model in which users are owners of smartphone devices was considered, which is a common scenario in the EU. It was estimated that
the average purchase price for a new smartphone in the EU is 320 EUR. This changes to less than 130 EUR and more than 480 EUR for low- and
high-end products, respectively (Cordella et al., 2020b).
The LCC effects of lean design concepts or changes in material composition of devices were not assessed. However, almost 70% of the purchase
price of smartphones is independent of parts and materials (Benton et al., 2015).
Operating costs include electricity consumption to recharge the battery and mobile service contract. They were considered equal to 0.2113
EUR/kWh (Eurostat, 2019), and 31.80 EUR/month (DG Connect, 2018) for a service contract including 5 GB of data, 100 calls, and 140 SMS. The
service contract cost decreases to 14.11 EUR for 100 MB, 30 calls, and 100 SMS (as EU average in 2017).
Product–service systems (PSS) appears a less common scenario for smartphones (Poppelaars et al., 2018) and were not directly assessed. The
main advantage of PSS business models is the enhanced possibility for service providers of collecting and reprocessing used devices. From a con-
sumer perspective, the LCC considerations provided in Section 3.2 can address the discussion of PSS business models. When the acquisition of a
smartphone is associated to a contract subscription with a telecommunication service provider, the product purchase cost is integrated in the sub-
scription costs and the consumer has the full ownership of the smartphone. Furthermore, smartphone contracts and replacement cycles havesimilar
lengths (Prakash et al., 2015), typically up to 2 years in the EU. Subscription contracts can vary when users do not own the device: for example, a
1-year subscription can cost from 15 EUR/month for low-end devices up to 100 EUR/month for high-end devices (Grover, 2021).
CORDELLA ET AL.455
2.3.2 Cost of more durable devices
The replacement cycle could be extended when more reliable and resistant devices are used (see Section 3.4). This is generally the case for high-
end devices and specific market segments (e.g., rugged smartphones), and to a lesser extent for medium-price devices (Cordella et al., 2021). The
purchase prices of average and high-end devices were considered in the assessment of extended use scenarios (EXT), where no repair operation is
needed because of enhanced design characteristics.
2.3.3 Repair costs
Battery or display replacement was considered in the repair scenarios (BC/DC). It was assumed that the replacement costs are 20 EUR for the
battery and 87 EUR for the display, when done by the user. When the replacement involves professional repairers, costs increase to 69 EUR for
the battery and 201 EUR for the display (Cordella et al., 2020b). Design concepts integrating reparability aspects could stimulate a reduction in the
repair costs. However, the influence of such aspects on LCC was not directly assessed.
2.3.4 Purchase price for used devices
The value of electronic devices drops over time (Culligan & Menzies, 2013). Makov et al. (2018) calculated residual values of smartphone models
from two brands. Average residual values were about 50–60%of the original price after 1 year, and 40–30% after 2 years.
In this study, the purchase price of second-hand device (RU scenario) was set equal to 149 EUR, considering that the product value drops to one
third of the original value, and that a 40% margin is applied. The purchase price of remanufactured products (RM scenario) was estimated as the sum
of costs for the replacement of battery and display by professionals: 270 EUR, corresponding to a market value loss of 16% (for an “as-new” device
but “old” model). However, the purchase price of remanufactured and new products could be the same in case remanufacturing results in “as-new”
devices with upgraded performance.
2.3.5 End of life costs and benefits
Economic benefits from the re-sale of old devices were not considered in the assessed scenarios but their possible effects are discussed in Sec-
tion 3.2.
Fees associated with WEEE services at the EoL were integrated in the product purchase price (Boyano Larriba et al., 2017).
The EoL recycling can also generate profit depending on factors such as collection rates, mass flow and design of devices, recycling technique
efficiency, as well as content and market value fluctuations of materials (Geyer & Doctori Blass, 2010; Renner & Wellmer, 2020). The profitability
could improve through separate processing of smartphones (Gurita et al., 2018), although mobile phones may not be an important source of income
for recyclers (Clift and Wright, 2000; Geyer & Doctori Blass, 2010). In any case, the relatively small profits from the recovery of materials are not
expected to affect the price of smartphones (Benton et al., 2015).
3RESULTS AND DISCUSSION
3.1 Carbon footprint
3.1.1 Baseline scenario (system aspects excluded)
In the scenario BL, smartphones are replaced every 2 years in a reference time of 4.5 years, which results in manufacturing and using 2.25 device
units. Old devices are kept unused at home and the usage of communication services is not considered. The storage of old devices at home is a
worst-case scenario leading over time to the piling-up of a stock of unused devices. In reality, some devices are sold or recycled at the end of the first
useful life (see Sections 3.1.3 and 3.3).
A CF of 77.2 kg CO2,eq over 4.5 years (equivalent to 17.2 kg CO2,eq/year) was quantified. Figure 2shows the breakdown of the CF by life cycle
stage: the main contribution comes from the BoM (62%), followed by device assembly (16%), distribution (11%), and use (11%).
456 CORDELLA ET AL.
FIGURE 2 Carbon footprint results for the baseline scenario(s) (reference: 4.5 years, 2.25 smartphone units)
FIGURE 3 Carbon footprint associated to the Bill of Materials of one smartphone unit and contribution of different parts
To understand the plausibility of the CF result for BL, this was compared with other studies, as reported in Table 2. Results are also in line with
the literature in highlighting the important contribution of materials and manufacturing processes to the CF of smartphones (78% for BL). Figure 3
shows the breakdown of the CF associated to materials for different parts of smartphones. The significant contribution of integrated circuit (IC),
printed wiring board (PWB), display, and camera is notable. The importance of IC, PWB, and display is confirmed by other studies (Andrae, 2016;
Clément et al., 2020; Ercan et al., 2016; Manhart et al., 2016; Proske et al., 2016). The importance of the camera unit was also highlighted by Proske
et al., 2016. A smaller contribution is instead quantified for the battery. This is comparablewith the results from Andrae (2016), although lower than
indicated in Ercan et al. (2016) and Proske et al. (2016).
Absolute results can vary depending on design characteristics, user behavior, system aspects, as well as modeling approach, assumptions, and
data used in different studies (Manhart et al., 2016; Clément et al., 2020). In particular, GHG emissions for IC are lower than in Andrae (2016), Ercan
et al. (2016),andProskeetal.(2016). Given the lack of primary data, it was necessary to consider proxies for the BoM. The deviation observed for
IC and PWB depends on weights and LCI datasets considered for these parts (see Supporting Information S1). However, the deviation is lessened
when IC and PWB are considered together and results converge in the identification of priority parts, at least qualitatively.
As calculated in Proske et al. (2016), materials and assembly of the device are dominant contributors to the life cycle impacts of smartphones
also for other impact categories (i.e., abiotic depletion potential, human toxicity, and ecotoxicity). Environmental impacts are due to manufacturing
processes and the extraction and sourcing of materials (Moberg et al., 2014): the acquisition of gold and other metals (e.g., palladium) can contribute
CORDELLA ET AL.457
to about 10% of the CF (Andrae, 2016), while cobalt, copper, gold, and silver are important for resource scarcity, eutrophication, and human toxicity
(Ercan et al., 2016).
3.1.2 Inclusion of system aspects in the baseline scenario
Figure 2shows the effects of including EoL recycling and usage of communication services in the scenario BL+.
Recycling reduced the CF by 5% compared to BL, thanks to recovery of materials and energy. State-of-the-art practices were considered in the
modeling. The application of more advanced recycling technologies could allow a more efficient recovery of materials, with CO2,eq saving that could
be 30% higher. On the contrary, the EoL could even result in environmental burdens if materials are not recovered (see Section 2.2.3).
It should also be observed that the approach followed in this work is to assume the 1:1 displacement of primary material by recycled material.
The displacement of primary materials in EoL modeling has been object of extensive discussion. Recent studies integrating consequential LCA con-
siderations (Palazzo et al., 2019,2020;Zink&Geyer,2017) indicate that recycled materials do not necessarily replace primary materials of the
same type. Therefore, actual benefits associated with the recycling of smartphones could be lower than calculated in this study.
Benefits of recycling would be better depicted through indicators relating to the scarcity of materials: according to Proske et al. (2016), recycling
of smartphones can reduce impacts associated with materials and manufacturing stage by 3% for GWP, 6% for ecotoxicity, 9% for abiotic depletion
of fossil fuels, 10% for human toxicity, and 59% for abiotic depletion of elements. Furthermore, recycling is important because smartphones includes
CRM (e.g., cobalt, rare earths) and minerals from conflict-affected and high-risk areas (e.g., gold) (Manhart et al., 2016).
The inclusion of communication services (i.e., mobile networks, fixed access networks, data centers, and transmission infrastructure) resulted in
the increase of the CF from 77.3 to 192.4 kg CO2,eq (2.5 times BL). This is due to the GHG emissions associated with the energy used for operating
networks and data centers: 55.7 kWh/year, compared to 4 kWh/year for battery recharging and 4.7 kWh consumed for the manufacturing of a
device. The impact of communication services is particularly relevant in case of internet content consumption with high bit rate (e.g., for video
streaming) (Schien et al., 2013), which requires a large transmission of data. The CF would increase considerably (1.8 times BL) also when data
consumption is halved.
The energy intensity of communication services is expected to decrease in the future since mobile-access network energy efficiency has
improved by 10-30% annually in recent years (IEA, 2020). However, the energy efficiency increase associated with newer network technolo-
gies may not continue with 5G (Pihkola et al., 2018), and the simultaneous growth of data traffic could offset expected efficiency improvements
(Ericsson, 2020; Lange et al., 2020; Montevecchi et al., 2020). In fact, data traffic volumes over mobile networks are increasing, and at a more dra-
matic rate than fixed-line traffic, mainly due to the increased consumption of video-streaming services (Cisco, 2015; Ericsson, 2020; Morley et al,
2018).
The significant and “hidden” contribution of networks and data centers (Andrae, 2016; Ercan et al., 2016; Suckling & Lee, 2015) calls for a sys-
tem approach in the analysis and mitigation of the impacts associated to ICT products and related communication networks (Schien et al., 2013;
Coroama & Hilty, 2014).
3.1.3 Comparison between scenarios implementing material efficiency strategies
Ta b l e 3and Figure 4provides CF results for BL and material efficiency scenarios described in Table 1.
The CF can significantly decrease by extending the average replacement cycle of devices from 2 to 3 years (EXT1: 30%) or 4 years (EXT2:
44%). The CF reduction was associated with fewer device units (and thus parts and materials) being allocated to the reference time of 4.5 years
(2.25, 1.5, and 1.125 units in case of replacement cycles of 2, 3, and 4 years, respectively).
In case of battery or display change in the first 2 years of use, the CF increased by 1% (BC) and 9% (DC) compared to BL, respectively. When
the change of battery comes with an extension of the replacement cycle to 3 years (BC1) or 4 years (BC2), the CF decreased by 29% and 44%,
respectively. The change of battery would not cause significant increase in the GHG emissions. In case of display change and replacement cycle
of 3 years (DC1) or 4 years (DC2), the CF decreased by 23% and 40%, respectively. The CF decreased because the impacts associated with the
manufacture of additional parts are compensated by the benefits of using smartphone devices longer.
The CF decreased to about half of BL when considering the purchase of remanufactured devices (RM), and the same energy consumption for
producing new and remanufactured devices (4.7 kWh per device). The CF decrease could be more significant if less energy were needed for the
reprocessing of devices. For example, the CF could decrease by 70% (compared to BL) considering 0.033 kWh for the refurbishment of a device
(Skerlos et al., 2003). The CF could decrease even more (byabout 80%) when refurbishment is not needed for the acquisition of second-hand devices
(RU).
Environmental savings are possible under the assumption that the purchase of used devices, inclusive of both remanufactured and second-hand
smartphones, perfectly replace the sale of new smartphone units. Actual benefits depend on “what” and “how much” is displaced (Zink et al., 2014).
458 CORDELLA ET AL.
TAB L E 3 Carbon footprint results for different scenarios implementing material efficiency strategies
Greenhouse gas emissions (kg CO2,eq)
Scenario 4.5 years 1 year Relative (%)
BL: baseline (2-year replacement cycle) 77.3 17.2 100
BL+:asBL+system aspects 192.4 42.8 249
EXT1: as BL with replacement cycle increased to 3 years 54.4 12.1 70
EXT2: as BL with replacement cycle increased to 4 years 42.9 9.5 56
BC: as BL with battery change 77.9 17.3 101
BC1: as EXT 1 with battery change 54.8 12.2 71
BC2: as EXT 2 with battery change 43.2 9.6 56
DC: as BL with display change 84.5 18.8 109
DC1: as EXT1 with display change 59.2 13.2 77
DC2: as EXT2 with display change 46.5 10.3 60
BC-DC: as BL with battery and display change 85.1 18.9 110
BC-DC1: as EXT1 with battery and display change 59.6 13.2 77
BC-DC2: as EXT2 with battery and display change 46.8 10.4 61
RM: Purchase of remanufactured device 37.0 8.2 48
RU: Reuse (purchase of second-hand device) 16.3 3.6 21
LD1: as BL with 10% lighter housing and display 75.5 16.8 98
LD2: as BL with 20% lighter housing and display 73.7 16.4 95
LD3: as BL with 30% lighter housing and display 71.9 16.0 93
Note: Absolute values calculated over 4.5 years, normalized to 1 year, and expressed in relative terms with reference to the BL.
FIGURE 4 CF and LCC results for selected scenarios implementing material efficiency strategies (underlying data used to create this figure
are provided in Supporting Information S2). Legend: BC1a (battery change by user, smartphone replacement cycle: +1 year), BC1b (battery change
by professional repairer, smartphone replacement cycle: +1 year), BC2 (battery change by user, smartphone replacement cycle: +2years),BL
(baseline), BL-HE (baseline, high-end device), BL-LE (baseline, low-end device), DC1a (display change by user, smartphone replacement cycle: +1
year), DC1b (display change by professional repairer, smartphone replacement cycle: +1 year), DC2 (display change by user, smartphone
replacement cycle: +2 years), EXT1 (extended use, smartphone replacement cycle: +1 year), EXT1-HE (extended use, high-end device, smartphone
replacement cycle: +1 year), EXT2 (extended use, smartphone replacement cycle: +2 years), EXT2-HE (extended use, high-end device, smartphone
replacement cycle: +2 years), LD3 (lean design, housing: 30% by weight), RM (remanufacture), RU (reuse). Note: System aspects excluded from
the assessment of the CF; higher service contract costs considered for the assessment of LCC
In the past, used smartphones were often sent to developing countries, where consumers owned no smartphone (Zink & Geyer, 2017). Zink et al.
(2014) estimated that the displacement of new smartphones by used devices could be equal to 0–5%. At a macro-scale, this would increase the
overall consumption of the sector (Makov & Font Vivanco, 2018;ZinkandGeyer(2017). However, the market of used smartphones has recently
become more important also in developed countries (Watson et al., 2017). Worldwide shipments of used smartphones are expected to increase
from 175.8 million units in 2018 to 332.9 million units in 2023 (IDC, 2019), against a total shipment of smartphones that is stagnant at around
CORDELLA ET AL.459
TAB L E 4 Life cycle costs for different scenarios implementing material efficiency strategies
Life cycle costs (EUR 2019)
Higher service costs Lower service costs
Scenario 4.5 years 1 year Relative (%) 4.5 years 1 year Relative (%)
BL: baseline (2-year replacement cycle, average device) 2441 542 100 1486 330 100
BL-HE: as BL, with high-end device 2801 622 115 1846 410 124
BL-LE: as BL, with low-enddevice 2014 448 82 1058 235 71
EXT1: as BL with replacement cycle increased to 3 years 2201 489 90 1246 277 84
EXT1-HE: as BL-HE with replacement cycle increased to 3
years
2441 542 100 1486 330 100
EXT2: as BL with replacement cycle increased to 4 years 2081 462 85 1126 250 76
EXT2-HE: as BL-HE with replacement cycle increased to 4
years
2261 502 93 1306 290 88
BC1a: as EXT1 with battery change made by the user 2231 496 91 1276 284 86
BC1b: as EXT1 with battery change made by a
professional repairer
2305 512 94 1349 300 91
BC2: as EXT2 with battery change made by the user 2104 468 86 1148 255 77
DC1a: as EXT1 with display change by the user 2332 518 96 1376 306 93
DC1b: as EXT1 with display change by a professional
repairer
2503 556 103 1547 344 104
DC2: as EXT2 with display change by the user 2179 484 89 1224 272 82
RM: purchase of remanufactured device 2329 518 95 1373 305 92
RU: reuse (purchase of second-hand device) 2057 457 84 1102 245 74
Note: Absolute values calculated over 4.5 years, normalized to 1 year, and expressed in relative terms with reference to the BL.
1.4 billion units (Statista, 2019). This can be partly explained by the fact that used smartphones can offer similar features of new devices at lower
price (IDC, 2019), at least until 5G networks and 5G-compatible smartphones achieve broad market penetration.
Furthermore, some authors (Makov & Font Vivanco, 2018; Makov et al., 2018;Zink&Geyer,2017) pointed out that benefits from the sale of
used devices could be partially offset by other rebound effects associated with the re-spending of economic savings. Makov and Font Vivanco
(2018) estimated that at least one third of the emission savings resulting from smartphone reuse could be lost because of rebound effects.
Material design change was assessed in terms of lean design, where quantities of materials for housing and display are decreased by 10% (LD1),
20% (LD2), and 30% (LD3). It was estimated that the CF can decrease by 27%. The display size was maintained unvaried. Lean design could help
counterbalance the increase of impacts associated with larger display sizes by reducing the amount of materials used. However, the actual variation
of impacts also depends on inherent characteristics of used materials and their supply chains. For example, a substantial CF reduction can result
from the use of renewable energy along the value chain and the recovery of metal scraps (Clément et al., 2020). Materials can also have an impact
on the generation of manufacturing scraps, the recycling process, and the market of recycled materials (Cordella et al., 2020b).
3.2 Life cycle costs
Different LCC scenarios are shown in Table 4and Figure 4. When higher service contract costs were considered, a LCC of 2441 EUR over 4.5 years
(542 EUR/year) was calculated for BL. LCC are 3.4 times the purchase price of single device units, with the larger contribution due to the use phase
(70.5%), mainly because of the service contract. LCC were 15% higher (+81 EUR/year) in case of high-end product (purchase price: +50%) and 17%
lower (92 EUR/year) for the low-end product (purchase price: 40%), under the assumption that devices are replaced every 2 years.
For longer replacement cycles of 3 or 4 years (EXT1, EXT2), LCC decreased by 10% (54 EUR/year) and 15% (81 EUR/year), respectively. If
the increased lifetime of the product is associated with high-end products (EXT1-HE, EXT2-HE), economic savings for consumers could be more
moderate or even offset by the higher purchase price.
In case longer replacement cycles come with the battery change (BC1a, BC1b, BC2) there could be still LCC savings for consumers, although the
intervention of professional repairers can lower them (BC1b). In case the longer replacement cycles come with the repair and change of the display
460 CORDELLA ET AL.
(DC1a, DC1b, DC2), there could be less or no LCC savings for consumers, due to higher repair costs. Facilitating the replacement of the displays by
users can help reduce LCC (DC1a, DC2). However, the service contract appeared a more significant factor.
Finally, a decrease of LCC by 5% (25 EUR/year) and 16% (85 EUR/year) was calculated for the purchase of remanufactured (RM) or reused
devices (RU) and higher service costs.
If lower service contract costs are considered (e.g., 14.11 EUR/month instead of 31.80 EUR/month), fluctuations over BL would be more signifi-
cant in all the scenarios due to the increased importance of the product-related costs.
No recovery of residual value through re-sale of old devices was considered so far. As discussed in Sections 3.1.1 and 3.3, a number of devices are
sold or recycled when approaching their EoL, which could allow recovering their residual value. Economic benefits from the re-sale of old devices
could be considerable for consumers, for example, up to 288 EUR over 4.5 years (64 EUR/year) for BL.
All in all, results indicate that the analyzed material efficiency strategies can be economically appealing for consumers. However, as discussed in
Section 3.1.3, it cannot be excluded that LCC saving can lead to re-spending rebound effects (Zink & Geyer, 2017).
3.3 Average EU scenario
Results reported above aim to analyze different scenarios of use and disposal for smartphones. Repair frequencies and EoL disposal routes (see
Section 2.2) were used to build an average EU scenario. Over a period of 4.5 years, this resulted in an average CF of 52 kg of CO2,eq (11.5 kg of
CO2,eq/year) and an average LCC of 2294 EUR (510 EUR/year) per user, which are 33% and 6% lower than in the BL, respectively. This supports the
importance of extending the replacement cycle of devices and promoting remanufacturing, reuse, repair, and recycling activities, with even more
evident benefits that could be observed with other metrics.
3.4 Technical measures to improve the material efficiency of smartphones
Results support the importance of material efficiency strategies for smartphones. In particular,considerable CF and LCC decreases were associated
with strategies oriented to extend the lifetime of device or its parts (see Figure 4).
This can be promoted through designs aimed at improving the reliability of the device, especially for electronics and parts as batteries and dis-
plays that could cause a premature replacement, as well as its resistance to accidental drops and its protection from water and dust (Cordella et al.,
2021).
A lifetime extension can be pursued also through repair, remanufacture, and re-sale of devices. Apart from ensuring the availability of quality-
compliant parts, these strategies can be enhanced through design-for-disassembly and modular design concepts (which would also enable hard-
ware and aesthetic upgrades), as well as the integration of functions for data transfer and deletion, password reset, and factory-setting restoration
(Cordella et al., 2020b; Peiró et al., 2017).
Durability considerations go beyond the hardware and cover also software and firmware (OCU, 2017). Measures that could avoid the prema-
ture functional obsolescence of smartphones (e.g., not working applications, unavailability of security updates) include the installation of sufficient
capacity (memory) in the device, as well as the availability of update support (e.g., operating system [OS] and/or security updates) and compatible
open source OS. Furthermore, the battery management software plays a key role in preserving the battery (Cordella et al., 2021).
Complementary measures should aim at facilitating the recycling of smartphones (Kasulaitis et al., 2018), in particular by enhancing the collection
of devices and the separation of parts and materials (Geyer & Doctori Blass, 2010).
It should also be observed that potential trade-offs associated with specific design concepts should be evaluated carefully. For example, products
designed to be more resistant may see their repairability limited, and vice versa (Cordella et a., 2021), while leaner design concepts may reduce the
flow of recyclable materials and hinder EoL recycling (Geyer & Doctori Blass, 2010). Profitability of recycling is particularly affected by the price
volatility of materials, with recycling itself partly contributing to decrease the price of primary materials (Clift & Wright, 2000). This scenario may
change in future since the transition to a “green economy” may have a substantial impact on the market of materials and provide incentives for
recycling (Renner & Wellmer, 2020).
Other EoL alternatives (reuse and remanufacture) may be more profitable than smartphone recycling (Geyer & Doctori Blass, 2010). However,
as discussed in Section 3.1.3, environmental benefits achievable with the purchase of remanufactured and second-hand devices may be counterbal-
anced by possible rebound and market expansion effects.
Furthermore, consumers may find it difficult to understand the benefits associated with specific design options and that their replacement
choices can be driven by perceived (psychological) obsolescence and the desire of having new devices (Makov & Fitzpatrick, 2019; Watson et al.,
2017). To be effective, the technical measures described above should be accompanied by the sharing of information about correct use, mainte-
nance and disposal of smartphones and associated benefits (e.g., why and how preserving the battery life, applying protective accessories, collecting
unused smartphones at the EoL).
CORDELLA ET AL.461
4CONCLUSIONS
This study analyzed how different material efficiency scenarios can affect the CF of smartphones, and their LCC from the perspective of consumers.
Technical measures to implement material efficiency strategies for this device were then discussed. The following conclusions are drawn.
4.1 Material efficiency scenarios and system aspects
The analysis of a sample of smartphone devices suggested an apparent increase in display size and memory configuration for newer models, which
can partly contribute to increase the CF of smartphones. However,other circumstances that can more significantly contribute to the overall increase
of GHG emissions from smartphones are their growing market penetration and short replacement cycles.
Extending the replacement cycle of smartphones (beyond 2 years) avoids the need of new devices, parts, and materials. This appeared as a win–
win solution to reduce CF and LCC, as depicted in Figure 4. Appreciable savings could be possible also in case of battery/display replacement. An
extension of the replacement cycle could be supported through design concepts that enhance hardware reliability, repairability, and upgradability,
as well through the availability of appropriate software and firmware solutions.
Remanufactured and second-hand devices could potentially yield greater benefits. However, results are dependent on the 1:1 displacement
assumption made in the assessment, based on which devices, parts, and materials can be perfectly replaced by secondary ones, while rebound
effects could occur in real markets.
Since a large portion of smartphones is not properly collected at the EoL, enhancing their collection is vital for product and material value reten-
tion. Measures to facilitate the recycling of smartphones are complementary to those promoting an extension of the lifetime of the device and its
parts. Additional benefits could come with the adoption of leaner designs, although this strategy was not assessed thoroughly.
However, it should be highlighted that the analysis of material efficiency aspects is complicated by the presence of possible trade-offs, and that
the effective implementation of material efficiency strategies rely on behavioral aspects and comprehensive information of users.
Furthermore, although the focus of this work was on material efficiency aspects, it was interesting to observe how major contributions to CF and
LCC are beyond the physical device boundaries.
The CF of smartphones is determined to a large extent by the usage of communication services. This calls for the importance of addressing their
energy efficiency and informing users about the “hidden” impacts associated with the use of smartphones.
From a LCC perspective, the main cost for consumers is instead associated to service contracts. Apart from their economic relevance, service
contracts can also play an environmentally strategic role for smartphones since they can affect the amount of data that users exchange and how
frequently devices are replaced.
4.2 Application of results and future research perspectives
This study can be used by decision-makers as a base of information to reduce the impacts associated with the production and consumption of smart-
phones. For example, it could: (i) guide purchase decisions of consumers and public procurers; (ii) support product design and business development
activities of manufacturers and service providers; (iii) feed discussion on product testing and/or regulation, as currently happening at the EU level
(Ecosmartphone, 2020).
This study focused on virtual scenarios for the EU and a limited number of quantitative indicators. Future research could build on this study by
considering further scenarios (e.g., focusing on network systems and PSS business models) based on real case studies, and the adoption of broader
sustainability assessment metrics (Peña et al., 2021), also to understand the magnitude of possible trade-offs and rebound effects that could reduce
circular economy benefits at a macro-scale (Makov et al., 2018;Zink&Geyer,2017).
However, gathering information for smartphones was a challenging process. This was handled through a transparent description of available
information and assumptions made, as well as the critical analysis of the results, also through the consultation of ICT experts. Further effort and
collaboration between manufacturers, researchers, and policy makers is necessary to develop and make available relevant data for smartphones
(and other electronics), such as BoM and LCI datasets, failure and repair frequencies, user statistics.
ACKNOWLEDGEMENTS
This publication does not imply a policy position of the European Commission. Neither the European Commission nor any person acting on behalf
of the Commission is responsible for the use that might be made of this publication.
The authors would like to thank the experts involved in the development of this study for the input provided. The experts represented a
broad range of stakeholders (European Commission’s services, Member States, industry, repair and recycling sector, NGOs, consumer testing
462 CORDELLA ET AL.
organizations, and the scientific community). The authors would also like to thank the editorial board of the Journal of Industrial Ecology, the review-
ers involved in the review process, and Mr. Shane Donatello (proofreading) for helping improve the overall quality of the work.
FUNDING INFORMATION
This work has been financially supported by the European Commission through the Administrative Agreement N. 070201/2015/SI2.719458/
ENV.A.1, signed by DG ENV and DG JRC.
CONFLICT OF INTEREST
The authors declare no conflict of interest.
ORCID
Mauro Cordella https://orcid.org/0000-0001- 9121-1134
Feli ce Alfie ri https://orcid.org/0000-0003-1147-719X
Javier Sanfelix https://orcid.org/0000-0002-4465-2276
REFERENCES
Allwood, J. M., Ashbya, M. F., Gutowski, T. G., & Worrell, E. (2011). Material efficiency: A white paper. Resources, Conservation & Recycling,55(3), 362–381.
Andrae Anders S.G. (2016). Life-Cycle Assessment of Consumer Electronics: A review of methodological approaches. IEEE Consumer Electronics Magazine,5,
(1), 51–60. http://doi.org/10.1109/mce.2015.2484639.
Apple. (2019). Environment.www.apple.com/environment
Askham, C., Hanssen, O. J., Gade, A. L., Nereng, G., Aaser, C. P., & Christensen, P. (2012). Strategy tool trial for office furniture. International Journal of Life Cycle
Assessment,17(6), 666–677.
Bakker, C., Wang, F., Huisman, J., & den Hollander, M. (2014). Products that go round: exploring product life extension through design. Journal of Cleaner
Production,69, 10–16.
Belkhir, L., & Elmeligi, A. (2018). Assessing ICT global emissions footprint: Trends to 2040 & recommendations. Journal of Cleaner Production,177(10), 448–
463.
Benton, D., Hazell, J., & Coats, E. (2015). A circular economy for smart devices: Opportunities in the US, UK and India. Green Alliance. https://www.green-alliance.
org.uk/resources/A%20circular%20economy%20for%20smart%20devices.pdf.
Boyano Larriba, A., Cordella, M., Espinosa Martinez, N., Villianueva Krzyzaniak, A., Graulich, K., Rüdinauer, I., Alborzi, F., Hook, I., & Stamminger, R.
(2017). Ecodesign and energy label for household washing machines and washer dryers. Publications Office of the European Union. https://op.europa.eu/en/
publication-detail/- /publication/533fa096-d971-11e7-a506- 01aa75ed71a1/language-en.
Cisco. (2015). The zettabyte era: Trends and analysis.WhitePaper.https://files.ifi.uzh.ch/hilty/t/Literature_by_RQs/RQ%20102/2015_Cisco_Zettabyte_Era.pdf
Clément, L. P.,Jacquemotte, Q., & Hilty, L. M. (2020). Sources of variation in life cycle assessments of smartphones and tablet computers. Environmental Impact
Assessment Review,84, 106416.
Clift, R., & Wright, L. (2000). Relationships between environmental impacts and added value along the supply chain. TechnologicalForecasting and Social Change,
65, 281–295.
Cordella, M., Alfieri, F., Clemm, C., & Berwald, A. (2021). Durability of smartphones: A technical analysis of reliability and repairability aspects. Journal of
Cleaner Production,286(2021), 125388.
Cordella, M., Alfieri, F., & Sanfelix Forner, J. (2020b). Guide for the assessment of material efficiency: Application to smartphones. Publications Office of the Euro-
pean Union. https://op.europa.eu/en/publication-detail/-/publication/19c79488-4641- 11ea-b81b-01aa75ed71a1/language- en. Accessed 24 February
2021.
Cordella, M., Alfieri, F.,Sanfelix, J., Donatello, S., Kaps, R., & Wolf, O. (2020a). Improving material efficiency in the life cycle of products: a review of EU Ecolabel
criteria. International Journal of Life Cycle Assessment,25, 921–935.
Cordella, M., & Hidalgo, C. (2016). Analysis of key environmental areas in the design and labelling of furniture products: Application of a screening approach
based on a literature review of LCA studies. Sustainable Production and Consumption,8, 64–77.
Coroama, V.C., & Hilty, L. M. (2014). Assessing Internet energy intensity: A review of methods and results. Environmental Impact Assessment Review,45, 63–68.
COWI & VHK. (2011). Methodology for ecodesign of energy-related products MEErP 2011: Methodology report. Part 1: Methods.https://ec.europa.eu/docsroom/
documents/26525
Culligan, K., & Menzies, B. (2013). The value of consumer electronics for trade-in and re-sale. WRAP report for the project no. HWP200-401. www.wrap.org.uk/
sustainable-electricals/esap/resource- efficient-business- models/reports/value-consumer-electronics- trade-and- re-sale
DG Connect. (2018). Mobile broadband prices in Europe 2017. European Union. https://ec.europa.eu/newsroom/dae/document.cfm?doc_id=50378.
Ecosmartphone. (2020). Ecodesign preparatory study on mobile phones, smartphones and tablets.https://www.ecosmartphones.info
Ellen MacArthur Foundation. (2012). In-depth Mobile phones.www.ellenmacarthurfoundation.org/news/in-depth-mobile- phones
Ercan, E. M. (2013). Global warming potential of a smartphone Using life cycle assessment methodology (Master of Science Thesis) KTH Royal Institute of
Technology of Stockholm, Sweden. TRITA-IM-EX 2013:01. http://kth.diva-portal.org/smash/get/diva2:677729/FULLTEXT01.pdf
Ercan M., Malmodin, J., Bergmark, P., Kimfalk, E., & Nilsson, E. (2016). Life cycle assessment of a smartphone. In Proceedings of ICT for Sustainability 2016 (pp.
124–133). Atlantis Press
Ericsson. (2020). Ericsson mobility report June 2020.www.ericsson.com/49da93/assets/local/mobility-report/documents/2020/june2020-ericsson-
mobility-report.pdf
CORDELLA ET AL.463
ETSI (European Telecommunications Standards Institute). (2019). ETSI TR 103 679 V1.1.1 (2019-05) Environmental Engineering (EE); Explore the challenges
of developing product group-specific Product Environmental Footprint Category Rules (PEFCRs) for smartphones. www.etsi.org/deliver/etsi_tr/103600_
103699/103679/01.01.01_60/tr_103679v010101p.pdf
European Union. (2009). Directive 2009/125/EC of the European Parliament and of the Council of 21 October 2009 establishing a framework for the setting
of ecodesign requirements for energy-related products. OJ L,285, 31.10.2009, pp. 10–35.
European Commission. (2015). COM(2015) 614 final: Closing the loop - An EU action plan for the Circular Economy. Communication from the Commission
to the European Parliament, the European Council, the Council, The European Economic and Social Committee and the Committee of the Regions. https:
//eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A52015DC0614. Accessed 24 February 2021.
European Commission. (2016). COM(2016) 773 final: Ecodesign Working Plan 2016–2019. Communication from the Commission. https://eur-lex.europa.
eu/legal-content/EN/TXT/?uri=CELEX%3A52016DC0773
European Union. (2017). Regulation (EU) 2017/1369 of the European Parliament and of the Council of 4 July 2017 setting a framework for energy labelling
and repealing Directive 2010/30/EU. OJ L, 198, 28.7.2017, pp. 1–23.
European Commission. (2019a). COM(2019) 640 final: The European Green Deal. Communication from the Commission to the European Parliament, the
European Council, the Council, The European Economic and Social Committee and the Committee of the Regions. https://eur-lex.europa.eu/legal-content/
EN/TXT/?uri=COM%3A2019%3A640%3AFIN
European Commission. (2019b). The new ecodesign measures explained.https://ec.europa.eu/commission/presscorner/detail/en/QANDA_19_5889
Eurostat. (2019). Electricity price statistics. https://ec.europa.eu/eurostat/statistics-explained/index.php/Electricity_price_statistics
Falaki, H., Mahajan, R., Kandula, S., Lymberopoulos, D., Govindan, R., & Estrin, D. (2010). Diversity in smartphone usage. In Proceedings of the 8th International
Conference on Mobile Systems, Applications, and Services (pp. 179–194). Association for Computing Machinery.
Geyer, R., & Doctori Blass, V. (2010). The economics of cell phone reuse and recycling. International Journal of Advanced Manufacturing Technology,47, 515–525.
Grover. (2021). https://www.grover.com/de-en/phones-and- tablets/smartphones
Gurita, L., Fröhling, M., & Bongaerts, J. (2018). Assessing potentials for mobile/smartphone reuse/remanufacture and recycling in Germany for a closed loop
of secondary precious and critical metals. Journal of Remanufacturing,8, 1–22.
Huawei. (2019). Product environmental information.https://consumer.huawei.com/en/support/product-environmental-information
Huijbregts, M. A. J., Rombouts, L. J. A., Hellweg, S., Frischknecht, R., Hendriks, A. J., van de Meent, D., Ragas, A. M. J., Reijnders, L., & Struijs, J. (2006). Is
cumulative fossil energy demand a useful indicator for the environmental performance of products? Environmental Science & Technology,40(3), 641–648.
Huysman, S., Sala, S., Mancini, L., Ardente, F., Alvarenga, R. A. F., De Meester, S., Mathieux, F., & Dewulf, J. (2015). Toward a systematized frameworkfor
resource efficiency indicators. Resources, Conservation & Recycling,95, 68–76.
IDC (International Data Corporation). (2019). Worldwide used samartphone forecast, 2019–2023.www.idc.com/getdoc.jsp?containerId=US45726219.
Accessed 10 July 2020.
IEA (International Energy Agency). (2020). Data centres and data transmission networks.www.iea.org/reports/data-centres-and- data-transmission- networks
IPCC (Intergovernmental Panel on Climate Change). (1992). Climate change: The IPCC 1990 and 1992 assessment.https://archive.ipcc.ch/ipccreports/1992%
20IPCC%20Supplement/IPCC_1990_and_1992_Assessments/English/ipcc_90_92_assessments_far_front_matters.pdf
IPCC (Intergovernmental Panel on Climate Change). (2013). In T. F., Stocker, D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex,
&P.M.Midgley(eds.),Climate change 2013: The physical science basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental
Panel on Climate Change (pp. 1535). Cambridge University Press.
Iraldo, F., Facheris, C., & Nucci, B. (2017). Is product durability better for environment and for economic efficiency? A comparative assessment applying LCA
and LCC to two energy-intensive products. Journal of Cleaner Production,140(3), 1353–1364.
IRP (2018). Re-defining Value The Manufacturing Revolution. Remanufacturing, Refurbishment, Repair and Direct Reuse in the Circular Economy. Nabil Nasr, Jen-
nifer Russell, Stefan Bringezu, Stefanie Hellweg, Brian Hilton, Cory Kreiss, and Nadia von Gries. A Report of the International Resource Panel. United Nations
Environment Programme. https://www.resourcepanel.org/file/1105/download?token=LPqPM9Bo.
ISO (International Organization for Standardization). (2006a). ISO 14040: 2006 Environmental management - life cycle assessment - principles and frame-
work.
ISO (International Organization for Standardization). (2006b). ISO 14044: 2006 Environmental management - life cycle assessment - requirements and guide-
lines.
Kasulaitis, B. V., Babbitt, C. W., & Krock, A. K. (2018). Dematerialization and the circular economy - Comparing strategies to reduce material impactsofthe
consumer electronic product ecosystem. Journal of Industrial Ecology,23(1), 119–132.
Lange, S., Pohl, J., & Santarius, T. (2020). Digitalization and energy consumption. Does ICT reduce energy demand?. Ecological Economics,176, 106760.
Makov, T., Fishman, T., Chertow, M. R., & Blass, V. (2018). What affects the second value of smartphones: Evidence from eBay. Journal of Industrial Ecology,
23(3), 549–559.
Makov, T., & Fitzpatrick, C. (2019). Planned obsolescence in smartphones? Insights from benchmark testing. In Proceedings of the 3rd PLATE Conference, Berlin,
Germany, 18–20 September 2019.
Makov T., Font Vivanco D. (2018). Does the circular economy grow the pie? The case of rebound effects from smartphone reuse. Frontiers in Energy Research,
6,http://doi.org/10.3389/fenrg.2018.00039.
Manhart, A., Blepp, M., Fischer,C., Graulich, K., Prakash, S., Priess, R., Schleicher, T., & Tür, M. (2016). Resource efficiency in the ICT sector. Final Report, November
2016. www.greenpeace.de/sites/www.greenpeace.de/files/publications/20161109_oeko_resource_efficency_final_full- report.pdf
Moberg, A., Borggren, C., Ambell, C., Finnveden, G., Guldbrandsson, F., Bondesson, A., Malmodin, J., & Bergmark, P. (2014). Simplifying a life cycle assessment
of a mobile phone. International Journal of Life Cycle Assessment,19(5), 979–993.
Montevecchi, F., Stickler, T., Hintemann, R., & Hinterholzer, S. (2020). Energy-efficient cloud computing technologies and policies for an eco-friendly cloud market.
Final Study Report. Vienna. https://ec.europa.eu/newsroom/dae/document.cfm?doc_id=71330
Morley, J., Widdicks, K., & Hazas, M. (2018). Digitalisation, energy and data demand: The impact of Internet traffic on overall and peak electricity consumption.
Energy Research & Social Science,38, 128–137.
OCU (Organización de Consumidores y Usuarios). (2017). Obsolescencia del software, una vida demasiado corta. Compra Maestra 423 Marzo 2017.
OCU (Organización de Consumidores y Usuarios). (2018). Los móviles acumulan el 51 % de las quejas de obsolescencia prematura. www.ocu.org/consumo-
familia/derechos-consumidor/noticias/obsolescencia- prematura
464 CORDELLA ET AL.
OCU (Organización de Consumidores y Usuarios). (2019). Tecnología: £qué marcas son las más fiables y satisfactorias?. www.ocu.org/tecnologia/telefono/
noticias/fiabilidad-satisfaccion- tecnologia
Palazzo, J., Geyer, R., Startz, R., & Steigerwald, D. G. (2019). Causal inference for quantifying displaced primary production from recycling. Journal of Cleaner
Production,210, 1076–1084.
Palazzo, J., Geyer, R., & Suh, S. (2020). A review of methods for characterizing the environmental consequences of actions in life cycle assessment. Journal of
Industrial Ecology,24(4), 815–829.
Peiró, L. T., Ardente, F., & Mathieux, F. (2017). Design for disassembly criteria in EU product policies for a more circular economy a method for analyzing
battery packs in PC-tablets and subnotebooks. Journal of Industrial Ecology,21(3), 731–741.
Peña, C., Civit, B., Gallego-Schmid, A., Druckman, A., Pires, A. C., Weidema, B., Mieras, E., Wang, F., Fava, J., Canals, L. M., Cordella, M., Arbuckle, P., Valdivia, S.,
Fallaha, S, Motta, W. (2021). Using life cycle assessment to achieve a circular economy. The International Journal of Life Cycle Assessment,http://doi.org/10.
1007/s11367-020- 01856-z.
Pihkola, H., Hongisto, M., Apilo, O., & Lasanen, M. (2018). Evaluating the energy consumption of mobile data transfer From technology development to
consumer behaviour and life cycle thinking. Sustainability,10(7), 2494.
Poppelaars, F., Bakker, C., & Van Engelen, J. (2018). Does access trump ownership? Exploring consumer acceptance of access-based consumption in the case
of smartphones. Sustainability,10(7), 2133.
Prakash, S., Dehoust, G., Gsell, M., Schleicher, T., & Stamminger, R. (2015). Einfluss der Nutzungsdauer von Produkten auf ihre Umweltwirkung: Schaffung einer
Informationsgrundlage und Entwicklung von Strategien gegen „Obsoleszenz“. ZWISCHENBERICHT: Analyse der Entwicklung der Lebens-, Nutzungs- und Ver-
weildauer von ausgewählten Produktgruppen. TEXTE 10/2015, Umweltforschungsplan des Bundesministeriums für Umwelt, Naturschutz, Bau und Reak-
torsicherheit Forschungskennzahl 371332315. www.umweltbundesamt.de/publikationen/einfluss- der-nutzungs- dauer-von-produkten-auf-ihre
Proske, M., Clemm, C., & Richter, N. (2016). Life cycle assessment of the Fairphone 2 Final report.www.fairphone.com/wp-content/uploads/2016/11/
Fairphone_2_LCA_Final_20161122.pdf
Renner, S., & Wellmer, F. W. (2020). Volatility drivers on the metal market and exposure of producing countries. Mineral Economics,33, 311–340.
Sanfelix, J., Cordella, M., & Alfieri, F. (2019). Methods for the assessment of the reparability and upgradabilityof energy-related products: Application to TVs. Publica-
tions Office of the European Union. https://op.europa.eu/en/publication-detail/-/publication/c0b344f5-216c- 11ea-95ab-01aa75ed71a1/language- en.
Schien, D., Shabajee, P., Yearworth,M., & Preist, C. (2013). Modeling and assessing variability in energy consumption during the use stage of online multimedia
services. Journal of Industrial Ecology,17(6), 800–813.
Skerlos, S. J. J., Morrow, W. R. R., Chan, K., Zhao, F., Hula, A., Seliger, G., Basdere, B., & Prasitnarit, A. (2003). Economic and environmental characteristics of
global cellular telephone remanufacturing. In 2003 IEEE International Symposium on Electronics and the Environment (pp. 99–104). IEEE.
Statista. (2019). Global smartphone shipments forecast from 2010 to 2023.www.statista.com/statistics/263441/global-smartphone-shipments- forecast
Suckling, J., & Lee, J. (2015). Redefining scope: the true environmentalimpact of smartphones? International Journal of Life Cycle Assessment,20(8), 1181–1196.
Tecchio, P., Ardente, F., & Mathieux, F. (2016). Analysis of durability, reusability and reparability - Application to washing machines and dishwashers. Publications
Office of the European Union. https://op.europa.eu/en/publication-detail/-/publication/72cd56e4-bab7- 11e6-9e3c-01aa75ed71a1/language- en.
TransformTogether. (2018). Creating sustainable smartphones: Scaling up best practice to achieve SDG 12.https://transform-together.weebly.com/uploads/7/9/
7/3/79737982/report_-_creating- sustainable-smartphone_scaling- up-best-practice-to-achieve-sdg-12.pdf
United Nations. (1997). Kyoto protocol to the United Nations Framework Convention on Climate Change.unfccc.int/sites/default/files/resource/docs/cop3/
l07a01.pdf
United Nations. (2015). Paris agreement.unfccc.int/files/essential_background/convention/application/pdf/english_paris_agreement.pdf
Watson, D., Gylling, A. C., Tojo, N., Throne-Holst, H., Bauer, B., & Milios, L . (2017). Circularbusiness models in the mobile phone industry. Nordisk Ministerråd.
Wernet, G., Bauer, C., Steubing, B., Reinhard, J., Moreno-Ruiz, E., & Weidema, B. (2016). The ecoinventdatabase version 3 (part I): Overview and methodology.
The International Journal of Life Cycle Assessment,21(9), 1218–1230.
Zink, T., & Geyer, R. (2017). Circular economy rebound. Journal of Industrial Ecology,21(3), 593–602.
Zink, T.,Maker, F., Geyer, R., Amirtharajah, R., & Akella, V. (2014). Comparative life cycleassessment of smartphone reuse: repurposing vs. refurbishment. The
International Journal of Life Cycle Assessment,19(5), 1099–1109.
SUPPORTING INFORMATION
Additional supporting information may be found online in the Supporting Information section at the end of the article.
How to cite this article: Cordella M, Alfieri F, Sanfelix J. Reducing the carbon footprint of ICT products through material efficiency
strategies: A life cycle analysis of smartphones. J Ind Ecol. 2021;25:448–464. https://doi.org/10.1111/jiec.13119
... In the Waste Electrical and Electronic Equipment (WEEE) sector, with used cell phones as a representative case, the predominant focus of research has been on remanufacturing strategies. However, there has been limited exploration of incentive measures for recycling, product quality standards, repair initiatives, and measures related to second-hand market sales (Cordella et al., 2021). Addressing the crucial issue of implementing multi-level utilization measures that consider product quality is essential for improving material efficiency (Allwood et al., 2011). ...
... The implementation of a material efficiency strategy has been demonstrated to facilitate sustainable resource utilization and environmental preservation, thereby yielding comprehensive benefits in terms of economics, environment, and society (Cordella et al., 2021). Therefore, this study designs a sustainable reverse logistics network for used cell phones (SRLN-UCP), encompassing the collection and used sale of used cell phones, as well as interconnected and interrelated facilities. ...
... Express system Packing material: 0.0067524 kg CO 2−eq /per phone Handling operations: 0.041329 kg CO 2−eq /kg Transportation: 2.3670⋅10 − 8kg CO 2−eq /(kg km) (Zhou et al., 2021) Quality test and categorization of used cell phones Testing equipments 1.9411 kg CO 2−eq /per phone Reuse: customers reuse used cell phones -−39.50 kg CO 2−eq /Per phone Recycle: Used cell phones are disassembled to obtain raw materials and components -1.64 kg CO 2−eq /Per phone(160 g) (Cordella et al., 2021) • Scope (Boundary): As depicted in Fig. 2, the system's boundary encompasses the entire process of used cell phone recovery, spanning from users to final disposal. It specifically includes various stages like transportation (public transportation, express delivery, fuel vehicle), cell phone quality testing, repair, disassembly, recycling, and reuse. ...
Article
Unsustainable production and consumption are driving a significant increase in global electronic waste, posing substantial environmental and human health risks. Even in more developed nations, there is the challenge of low collection rates. In response, we integrate offline and online trading systems and design a material efficiency strategy for used cell phones. We propose a new multi-objective optimization framework to maximize profit, carbon emissions reduction, and circularity in the process of recycling and treatment. Considering multi-period, multi-product, multi-echelon features, as well as price sensitive demand, incentives, and qualities, we established a new multi-objective mixed-integer nonlinear programming optimization model. An enhanced, Fast, Non-Dominated Solution Sorting Genetic Algorithm (ASDNSGA-II) is developed for the solution. We used operational data from a leading Chinese Internet platform to validate the proposed optimization framework. The results demonstrate that the reverse logistics network designed achieves a win–win situation regarding profit and carbon emission reduction. This significantly boosts confidence and motivation for engaging in recycling efforts. Online recycling shows robust profitability and carbon reduction capabilities. An effective coordination mechanism for pricing in both online and offline channels should be established, retaining offline methods while gradually transitioning towards online methods. To increase the collection rate, it is essential to jointly implement a transitional strategy, including recycling incentives and subsidy policies. Additionally, elevating customer environmental awareness should be viewed as a long-term strategy, mitigating the cost of increasing collection rates during the market maturity stage (high collection rates).
... Possibly the biggest concern is how ICTs impact greenhouse gas emissions (GHG) that cause climate change. Researchers have argued that the production and use of ICTs can be a source of greenhouse gas emissions (Louis-Philippe et al., 2020;Cordella et al., 2021;Proske, 2022) but that information systems are also a tool for reducing emissions at the country, city, and industry levels (Dedrick, 2010;ITU, 2020;Chien et al., 2021;Almalki et al., 2023;Park et al., 2023). ...
... Over time, the impacts of smartphone use will likely be more significant as conventional PCs are replaced with the use of smartphones and their apps that manage energy use and benefit the environment (Almaki et al., 2021;Lucas et al., 2023). Smartphone production that uses less polluting and more energy-efficient components will also significantly reduce the carbon footprint (Cordella, et al., 2021). ...
Article
Research suggests that information and communication technologies (ICTs) have a nonlinear relationship with CO2 emissions, specifically an inverted U-shaped curve similar to the environmental Kuznets curve (EKC). While extant research has investigated the relationship using an ICT index, there has been no research looking at smartphones, the use of which has been closely associated with the explosive growth in the use of mobile apps and a build-out of large information systems to support their use. To address this gap, this research examines the relationship of ICTs and smartphones with CO2 emissions by employing a country-level data set for the period from 2009 to 2017. Our results show that the relationship of ICTs with CO2 emissions takes an inverted U-shaped curve form, consistent with the EKC hypothesis. Our results also show that CO2 emissions increase with initial increases in smartphone capital stock but decrease as smartphone stock increases further. These findings imply that carbon emissions go up with the penetration of ICTs in poorer countries but in wealthier countries, ICT penetration and smartphone stock are related to lower CO2 emissions. The results should not be taken as evidence that ICTs cannot lead to greater sustainability in poorer countries but should be seen as a call for the IS community to help all countries apply existing knowledge and develop new knowledge to use ICTs to reduce emissions in response to the immediate challenge of climate change.
... The mass of waste generated for each product by year was calculated by multiplying the amount (in units) by the average weight values of smartphones and laptops. The average weight of smartphones was 154.54 g by product unit (Ercan, 2016;Babbitt et al., 2020;Cordella et al., 2021). Notebooks' average weight was 2.711 kg by product unit (Abbondanza & Souza, 2019;Babbitt et al., 2020;Kasulaits et al., 2015). ...
... The estimate of the generation of LIBs waste (in mass) was calculated by multiplying the total mass value of the products by the percentage referring to the mass of the LIBs: 27.3% weight for LIBs in smartphones and 9.34% weight for LIBs in laptops (e.g., Wang et al., 2016;Cordella et al., 2021). ...
Article
Recycling lithium-ion batteries (LIBs) is a solution to minimise the environmental problems caused by the consumption of natural resources and the generation of hazardous waste. This paper aims to assess the potential environmental impacts and benefits of four scenarios for recycling LIBs from smartphones and laptops using Life Cycle Assessment (LCA). The methodological approach followed four steps: i) scenario modelling representing the current and future situations of LIBs End-of-Life (EoL) management from smartphones and laptops; ii) estimating smartphones, laptops and respective LIBs waste generation; iii) mapping representative recycling options; and iv) assessment of potential environmental impacts using LCA with 16 ILCD midpoint categories. The results revealed that hydrometallurgical recycling in Brazil could be less harmful than pyrohydrometallurgical recycling in Europe in 12 impact categories. The benefits of recycling are mainly of Co and Ni recovery. Results of scenarios indicate that the more optimistic scenario, which includes expanding Reverse Logistics to 50% of collection, internal recycling to 75%, and reducing of LIBs waste sent to landfills in 44%, had the best environmental performance in all 13 impacts categories. For the Climate change category, scenario 4 presents net environmental benefits of -1.83E+05 kgCO2eq while scenarios 1, 2 and 3 do not present a net environmental benefit. Scenarios assessment shows that more significant environmental benefits are achieved when the formal collection rate is increased, and the less impactful technology option makes the recovery of materials. These results can help decision-makers promote the management and recycling more sustainable of LIBs waste.
... Efforts exist to implement CE models, with the primary strategies commonly used by companies to extend the lifecycle of devices, including durable design, maintenance, repair, re-use, remanufacturing, refurbishing, and recycling (Deng et al. 2021). In Cordella, Alfieri, and Sanfelix (2021), various scenarios are proposed to estimate the increasing impact of smartphones to minimise environmental repercussions. Additionally, there are positive benefits when the device's lifecycle is extended by at least two years, as it mitigates the need for updated devices and reduces environmental impact. ...
Article
Full-text available
Smartphones are indispensable tools for daily tasks; nevertheless, their short lifespan of about two years contributes to a disproportionate increase in environmental waste. Although current initiatives explore reusing specific smartphone components, such as metallic parts, the scope of these efforts still needs to be expanded, necessitating more comprehensive strategies to address the growing waste generation. Additionally, end-users play a pivotal role in determining the fate of obsolete smartphones and in adopting sustainable disposal practices to mitigate environmental damage after the devices are no longer useful to them. This proposal describes the scope to obtain a circular economy approach at a macro-level environmental impact. The strategy aims to employ obsolete smartphones while reducing environmental im pacts and facilitating efficient device disposal. The authors employ the S4 framework to support sustainable product development at a macro-level, emphasising sensing, smart, sustainability, and social dimensions. However, it is essential to note that the current solution applies only to smartphones with functional features, including intact displays, operational batteries, accessible cameras and sensors, and functional power systems, obtaining a level three according to the S4 framework, which describes limited human intervention.
... It is therefore important to design measurement systems with materials that are renewable or can be recycled, and to ensure that the manufacturing process minimizes waste and pollution. Finally, the disposal of measurement systems at the end of their useful life is also an important environmental consideration [15]. Measurement systems may contain hazardous materials that can contaminate the environment if not disposed of properly. ...
Article
Full-text available
Higher education institutions (HEIs) play a fundamental role in sustainability, promoters of innovation, science, and technology. Therefore, every day more institutions are joining the fight against global warming. One of the contributions of HEIs is the carbon footprint (CF) report, to implement policies and management systems to establish strategies to reduce polluting gas emissions from their campuses. In the present study, a systematic review was carried out for 50 reports of CF, where 94% of the studies were published from 2018 to 2022. This research compiles methodologies, scope, results, and trends in Carbon Footprint calculations and provides a procedure to evaluate CF on college campuses. This research shows that the most evaluated emission sources were the consumption of electrical energy (78%), transportation (74%), and the use of fuels (64%). In addition, the HEIs with the lowest emission factors for electricity consumption are Finland, England, and Colombia. Furthermore, establishing a specific carbon footprint guideline for universities would improve reports and allow better comparisons between HEIs.
Article
Full-text available
With the global concern over climate change, many countries around the world have pledged to achieve carbon peaking and carbon neutrality goals. Carbon footprint (CF) analysis, as an important research method to evaluate carbon emissions, has gained significant traction in the academic community. This study aims to offer a comprehensive overview of this research domain, addressing existing gaps by conducting a bibliometrics analysis. Moreover, social network analysis (SNA) is conducted to uncover the relationships among different countries, authors, and institutions. Co-occurrence analysis of keywords and citation analysis of publications and corresponding references are also conducted to explore the core research topics in this field, including popular CF accounting methods. Results show that there has been growing interest in CF-related research from 2007 to 2022, with increasing amounts of publications, references, authors, and published countries. The most productive journals, countries, authors, and institutions are identified, and the collaboration networks among different academic groups are also analyzed. In addition, sustainability assessment, consumption-based CF accounting, and emission mitigation potential assessment are identified as research hotspots. Specific research topics include CF accounting at national and household scales, as well as for agricultural systems and universities. Life cycle assessment (LCA), input-output analysis (IOA), and Intergovernmental Panel on Climate Change (IPCC) accounting method are the most commonly applied methods in this field. Therefore, the advantages and disadvantages of these methods are specifically summarized and compared. In general, this study can provide comprehensive information for stakeholders interested in the CF-related field.
Article
Full-text available
Ironically, healthcare systems are key agents in respiratory-related diseases and estimated deaths because of the high impact of their greenhouse gas emissions, along with industry, transportation, and housing. Based on safety requirements, hospitals and related services use an extensive number of consumables, most of which end up incinerated at the end of their life cycle. A thorough assessment of the carbon footprint of such devices typically requires knowing precise information about the manufacturing process, which is rarely available in detail because of the many materials, pieces, and steps involved during the fabrication. Yet, the tools most often used for determining the environmental impact of consumer goods require a bunch of parameters, mainly based on the material composition of the device. Here, we report a basic set of analytical methods that provide the information required by the software OpenLCA to calculate the main outcome related to environmental impact, greenhouse gas emissions. Through thermogravimetry, calorimetry, infrared spectroscopy, and elemental analysis, we proved that obtaining relevant data for the calculator in the exemplifying case of endoscopy tooling or accessories is possible. This routine procedure opens the door to a broader, more accurate analysis of the environmental impact of everyday work at hospital services, offering potential alternatives to minimize it.
Article
Full-text available
The current global interest in circular economy (CE) opens an opportunity to make society's consumption and production patterns more resource efficient and sustainable. However, such growing interest calls for precaution as well, as there is yet no harmonised method to assess whether a specific CE strategy contributes towards sustainable consumption and production. Life cycle assessment (LCA) is very well suited to assess the sustainability impacts of CE strategies. This position paper of the Life Cycle Initiative (hosted by UNEP) provides an LCA perspective on the development, adoption, and implementation of CE, while pointing out strengths and challenges in LCA as an assessment methodology for CE strategies.
Article
Full-text available
Smartphones are available on the market with a variety of design characteristics and purchase prices. Recent trends show that their replacement cycle has become on average shorter than two years, which comes with associated environmental impacts that could be mitigated through a prolonged use of such devices. This paper analyses limiting states and design trends affecting the durability of smartphones, and identifies reliability and repairability measures to extend the product lifetime. Technical trade-offs between reliability and repairability aspects are also discussed. Smartphones are often replaced prematurely because of socio-economic and technical reasons. Specific hardware parts (e.g. display, battery, back cover), as well as software, can be critical. Increasing the reliability of smartphones can reduce the occurrence of early replacements. Apart from the bottom-line consideration of reliability aspects for electronics, this can be pursued through the design of devices which: i) are resistant to mechanical stresses; ii) implement durable batteries; iii) offer sufficient adaptability to future conditions of use (e.g. in terms of software/firmware updates, memory and storage capacity). However, if and when failures occur, repairs have to be rapid and economically viable. This can be facilitated through modular design concepts, ease of disassembly of key parts, availability of spare parts and repair services. As common elements of the two strategies, easily-available instructions on use, maintenance and repair are also needed. The analysis of devices on the market suggests that it is possible to design satisfactorily reliable devices without compromising repairability excessively. However, trade-offs between these two aspects can occur. Considerations about reliability and/or repairability should be integrated in the design of all smartphones. The findings of this paper can be used by decision makers (e.g. manufacturers, designers, consumers and policy makers) interested in improving the durability of smartphones. This is particularly timely considering the policy attention on smartphones at the EU level.
Article
Full-text available
The current global interest in circular economy (CE) opens an opportunity to make society’s consumption and production patterns more resource efficient and sustainable. However, such growing interest calls for precaution as well, as there is yet no harmonised method to assess whether a specific CE strategy contributes towards sustainable consumption and production. Life cycle assessment (LCA) is very well suited to assess the sustainability impacts of CE strategies. This position paper of the Life Cycle Initiative (hosted by UNEP) provides an LCA perspective on the development, adoption, and implementation of CE, while pointing out strengths and challenges in LCA as an assessment methodology for CE strategies.
Article
Full-text available
Life Cycle Assessment (LCA) studies and reports on smartphones and tablet computers are analysed to detect the sources of variation across their results, considering the impact on global warming potential over 100 years (GWP100). The production and use phases are undoubtedly the life cycle phases contributing most strongly. Existing life cycle inventories (LCI) were analysed to determine the most important components, and a normalization of the use phases was performed. The results highlight the prevalence of the production phase. Integrated circuits (ICs) play a major role, and the estimation of their impact should be thoroughly scrutinized. Finally, the location of the production plants is crucial as electricity generation accounts for a significant part of the GWP. Assumed electricity mixes explain much of the variations in both production and use phases.
Article
Full-text available
This article investigates the effect of digitalization on energy consumption. Using an analytical model, we investigate four effects: (1) direct effects from the production, usage and disposal of information and communication technologies (ICT), (2) energy efficiency increases from digitalization, (3) economic growth from increases in labor and energy productivities and (4) sectoral change/tertiarization from the rise of ICT services. The analysis combines empirical and theoretical findings from debates on decoupling energy consumption from economic growth and from debates on green IT and ICT for sustainability. Our main results: Effects 1 and 3 tend to increase energy consumption. Effects 2 and 4 tend to decrease it. Furthermore, our analysis suggests that the two increasing effects prevail so that, overall, digitalization increases energy consumption. These results can be explained by four insights from ecological economics: (a) physical capital and energy are complements in the ICT sector, (b) increases in energy efficiency lead to rebound effects, (c) ICT cannot solve the difficulty of decoupling economic growth from exergy, (d) ICT services are relatively energy intensive and come on top of former production. In future, digitalization can only boost sustainability when it fosters effects 2 and 4 without promoting effects 1 and 3.
Article
Full-text available
Understanding the environmental consequences of actions is becoming increasingly important in the field of industrial ecology in general, and in life cycle assessment (LCA) more specifically. However, a consensus on how to operationalize this idea has not been reached. A variety of methods have been proposed and applied to case studies that cover various aspects of consequential life cycle assessment (CLCA). Previous reviews of the topic have focused on the broad agenda of CLCA and how different modeling frameworks fit into its goals. However, explicit examination of the spectrum of methods and their application to the different facets of CLCA are lacking. Here, we provide a detailed review of methods that have been used to construct models of the environmental consequences of actions in CLCA. First, we cover the following structural modeling approaches: (a) economic equilibrium models, (b) system dynamics models, (c) technology choice models, and (d) agent‐based models. We provide a detailed review of particular applications of each model in the CLCA domain. The advantages and disadvantages of each are discussed, and their relationships with CLCA are clarified. From this, we are able to map these models onto the established aspects of CLCA. We learn that structural models alone are not sufficient to quantify the uncertainty distributions of underlying parameters in CLCA, which are essential components of a robust analysis of consequences. To address this, we provide a brief introduction to a counterfactual‐based causal inference approach to parameter identification and uncertainty analysis that is emerging in the CLCA literature. We recommend that one potential research path forward is the establishment of feedback loops between empirical estimates and structural models.
Technical Report
Full-text available
Improving the material efficiency of products has the potential of bringing benefits to the environment and to the economy, by saving resources and avoiding production of waste. However, improved design of products needs to be assisted by appropriate assessment methods. In this context, the Joint Research Centre Directorate B, Circular Economy & Industrial Leadership unit (JRC B.5), prepared a guidance for the assessment of material efficiency of products (GAME) addressing two practical targets: - The identification of key material efficiency aspects of products; - The definition of tangible improvement measures. The guidance, which is described in this report in parallel to its application to smartphones, is based on the analysis of technical and functional aspects of products, as well as on the definition of life cycle assessment scenarios targeting environmental and economic impacts. The product group “smartphones” is used as an illustrative case study to show how to implement this guidance for the analysis. Possible actions for improving the performance of smartphones with respect to material efficiency are investigated. Aspects like durability, reparability, upgradability, recyclability and use of materials are analysed.
Technical Report
Full-text available
Improving the material efficiency of products is important to reduce their environmental impacts. In particular, an improvement of the reparability and upgradability of products can be beneficial to the environment and to the economy by limiting the early replacement of products and thus saving resources. However, the design of products needs to be assisted by appropriate assessment methods. In this context, the Joint Research Centre Directorate B, Circular Economy & Industrial Leadership unit, has compiled multi-level approaches for assessing the reparability and upgradability of products. This report describes such approaches and their application to TVs, with the overarching goal of improving the knowledge about the assessment of the reparability and upgradability of energy related products (ErP). The document is built on in-house research and on input received from stakeholders during two written consultations which took place in April 2018 and in April 2019. The following approaches have been considered, based on the preliminary identification of priority parts:  Quantitative methods, including Life Cycle Assessment (LCA) and calculation of disassembly steps/times, which are more complex in terms of data and calculation needs;  Qualitative methods, which aim to provide lists of pass/fail requirements influencing the repair and upgrade of TVs;  Quali-quantitative methods, which fall in between the previous methods in terms of complexity and aim to develop scoring criteria with which to rank a product. Key findings for TVs are the following:  The most relevant parts for repair and upgrade of TVs are the main board, T-con board, sound board, power board, inverter board, IPS/EPS, speakers and backlights (lamps/LEDs).  Manufacturing of circuit boards is the major contributor to the environmental impacts of a TV. In case of failure of these parts, repairing a TV (instead of replacing it with a new product) can be convenient only if the repaired product is used for a considerably longer period of time (about 35-40% longer than an expected lifetime of 10 years). For other parts which present lower environmental impacts, like the speakers, repair can be considered as an environmentally convenient alternative after a marginal increase of the time of use.  The analysis of disassembly steps and times seems to indicate that there is little variance for these parameters among different products; other parameters like availability and cost of spare parts could be more relevant in determining the likelihood of repairing or not the product. Given the similarities of TVs with other types of electronic displays, for which the main difference is the absence of a tuner card, it is in expected that the outcomes of this study could be in general extended to a large extent also to other electronic displays. Nevertheless, similarities and differences with TV displays should be carefully assessed on a product basis before translating specific results to other types of display. The study can support standardisation work on material efficiency of TVs and other Energy-related Products (e.g. the ongoing CEN/CENELEC JTC10 standardisation process) as well as the possible methodological refinement and applications of the Repair Score System developed by JRC. The information gathered even constitutes a reference for policy making and designers (e.g. the revision of the EU Ecolabel requirements for TVs or the potential development of a reparability label).
Article
Full-text available
The paper focuses on minor metals and coupled elements and aspires to understand individual incidents of imbalance on the mineral markets during the last 100 years and gain insight into the acting dynamics—those dynamics are commodity-specific but remain largely unchanged in their nature to date—and to identify the factors in play. The conclusions allow for a critical analysis of the widespread security-of-supply narrative of industrialized countries. They point at a market that is mostly a buyers’ market, in which prices and their volatility are largely dictated by shifting demand patterns and much less by supply constraints. Neither high country concentration nor poor governance seem to have a substantial or lasting impact on market balance. Short-term market imbalances are generally neutralized by a dynamic reaction on the demand side via substitution, efficiency gains or technological change. The paper also assesses the impact of those quickly shifting demand patterns and the related price volatilities on producing countries. It shows how mineral price volatilities can expose developing countries’ economies to significant economic risk, if their economy is heavily dependent on mineral production. Two cases that illustrate country exposure are explored in detail—the saltpeter crisis in Chile and the tin crisis in Bolivia. Both led to state bankruptcy. The paper concludes with an attempt to quantify economic exposure of producing countries to price volatilities of specific metals and suggests policies that adapt to the characteristic challenges of highly volatile demand.