U.S. Environmental Protection Agency
Office of Resource Conservation and Recovery
Documentation for Greenhouse Gas Emission and
Energy Factors Used in the Waste Reduction Model
(WARM)
Electronics
May 2019
Prepared by ICF
For the U.S. Environmental Protection Agency
Office of Resource Conservation and Recovery

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WARM Version 15
Table of Contents
May 2019
Table of Contents
1 Electronics	1-1

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1 ELECTRONICS
1.1 INTRODUCTION TO WARM AND ELECTRONICS
This chapter describes the methodology used in EPA's Waste Reduction Model (WARM) to
estimate streamlined life-cycle greenhouse gas (GHG) emission factors for desktop central processing
units (CPUs), portable electronic devices, flat-panel displays, cathode ray tube (CRT) displays, electronic
peripherals, and hard-copy devices beginning at the point of waste generation. The WARM GHG
emission factors are used to compare the net emissions associated with these six types of electronics in
the following four materials management alternatives: source reduction, recycling, landfilling, and
combustion. For background information on the general purpose and function of WARM emission
factors, see the Introduction & Overview chapter. For more information on Source Reduction. Recycling.
Landfilling. and Combustion, see the chapters devoted to those processes. WARM also allows users to
calculate results in terms of energy, rather than GHGs. The energy results are calculated using the same
methodology described here but with slight adjustments, as explained in the Energy Impacts chapter.
The following electronic material types are modeled in WARM:
•	Desktop CPUs. Desktop CPUs include the stand-alone processing unit for a desktop computer
and does not include the monitor or any peripherals (e.g., mice, keyboards).
•	Portable electronic devices. Portable electronic devices include laptops, e-readers, tablets, smart
phones, and basic mobile phones.
•	Flat-panel displays. Flat-panel displays include LED and liquid crystal display (LCD) televisions,
plasma televisions, and LED and LCD computer monitors.
•	CRT displays. CRT displays include CRT televisions and CRT computer monitors. While CRT
displays are no longer manufactured, many are still entering the waste stream in the U.S.
•	Electronic peripherals. Electronic peripherals consist of electronic devices used in conjunction
with other products and include keyboards and mice.
•	Hard-copy devices. Hard-copy devices include electronic devices used for preparing hard-copy
documents, including printers and multi-function devices.
•	Mixed electronics. The weighted average mix of electronic material types represented by the
mixed electronics material is based on data from The Electronics Recycling Landscape Report,
prepared for the Closed Loop Foundation (Mars et al., 2016) and presented in Exhibit 1-1. This
weighting represents the mass of electronics generated for waste in 2015.
Exhibit 1-1: Relative Prevalence of Electronics in the Waste Stream in 2015 (Mars et al., 2016)
Material
Weighting
Desktop CPUs
11%
Portable Electronic Devices
5%
Flat-Panel Displays
23%
CRT Displays
44%
Electronic Peripherals
2%
Hard-Copy Devices
15%
Upon disposal, electronics can be recovered for recycling, sent to a landfill or combusted.
Exhibit 1-2 shows the general outline of materials management pathways in WARM. Recycling
electronics is an open-loop process, meaning that components are recycled into secondary materials
such as steel sheet, lead bullion, copper wire, and aluminum sheet and not necessarily recycled back
1-1

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into new electronics. Electronics are collected curbside and at special events, or individuals can bring
them to designated drop-off sites such as at electronics stores. Once electronics have been collected for
recycling, they are sent to Material Recovery Facilities (MRFs) that specialize in separating and
recovering materials from electronic products. Building on
Exhibit 1-2, a more detailed flow diagram showing the open-loop recycling pathways of
electronics is provided in Exhibit 1-3.
Exhibit 1-2: Life Cycle of Electronics in WARM
Raw Material Acquisition,
Processing, & Transport
(Virgin Manufacture Only)
Raw Material Acquisition,
Processing, & Transport
(Virgin Manufacture Only)
Secondary Product
Manufacture: Recycling
Offsets Virgin
Manufacture
Transport to Recycled
Secondary Product
Manufacturing Facilities
Transport to
Retail Facility
I ransport to
Retail Facility
Product Use
Product Use
End of Life
Steel
recovered for
recycling
Ash Residue
Landfilling
Electronics
End of Life
Not
Modeled
Composting
Steps Not Included in	Not Modeled for This
WARM	Material!
Anaerobic
Not
Modeled
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Exhibit 1-3: Detailed Recycling Flows for Electronics
Electronics
Not Modeled for This
Material
in WARM
Steel Transport
to Metals
Recycling
Retail Transport,
Product Use, & End
	of Life	
Plastics Transport
to Plastics
Recycling

Retail Transport,
Product Use, & End
of Life
Retail Transport,
Product Use, & End
of Life
Retail Transport,
Product Use, & End
	of Life	
Retail Transport,
Product Use, & End
	of Life	
Retail Transport,
Product Use, & End
of Life
Retail Transport,
Product Use, & End
of Life
Retail Transport,
Product Use, & End
of Life
1.2 LIFE-CYCLE ASSESSMENT AND EMISSION FACTOR RESULTS
The life-cycle boundaries in WARM start at the point of waste generation, or the moment a
material is discarded, and only consider upstream emissions when the production of materials is
affected by end-of-life materials management decisions. Recycling and source reduction are the two
materials management options that impact the upstream production of materials, and consequently are
the only management options that include upstream GHG emissions. For more information on
evaluating upstream emissions, see the chapters on Recycling and Source Reduction.
WARM includes source reduction, recycling, landfilling and combustion pathways for materials
management of electronics. Anaerobic digestion and composting are not included as a pathway for
materials management of electronics. As Exhibit 1-4 illustrates, most of the GHG emissions from end-of-
life management of electronics occur from the waste management of these products, while most of the
GHG savings occur from offsetting upstream raw materials acquisition and manufacturing of other
secondary materials that are recovered from electronics.
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Exhibit 1-4: Electronics GHG Sources and Sinks from Relevant Materials Management Pathways

GHG Sources and Sinks Relevant to Electronics
Materials Management

Changes in

Strategies for
Raw Materials Acquisition and
Forest or Soil

Electronics
Manufacturing
Carbon Storage
Materials Management
Source Reduction
Offsets
•	Transport of raw materials and
intermediate products
•	Virgin process energy
•	Virgin process non-energy
•	Transport of electronics to
point of sale
NA
NA
Recycling
Emissions
•	Transport of recycled materials
•	Recycled process energy
•	Recycled process non-energy
Offsets
•	Emissions from producing
plastic, steel, copper,
aluminum, lead, nickel,
precious metals, and lithium
cobalt oxide from virgin
material
NA
Emissions
•	Collection of electronics and
transportation to recycling
center
•	Demanufacturing electronics
•	Landfilling the faction of
electronics not recovered for
recycling
Composting
Not applicable because electronics cannot be composted
Landfilling
NA
NA
Emissions
•	Transport to landfill
•	Landfilling machinery
Combustion
NA
NA
Emissions
•	Transport to WTE facility
•	Combustion-related C02 and
N20
Offsets
•	Avoided utility emissions
•	Steel recovery
Anaerobic Digestion
Not applicable because electronics cannot be anaerobically digested
NA = Not applicable.
WARM analyzes all of the GHG sources and sinks outlined in Exhibit 1-4 and calculates net GHG
emissions per short ton of electronics inputs as shown in Exhibit 1-5. For more detailed methodology on
emission factors, please see the sections below on individual materials management strategies.
Exhibit 1-5: Net Emissions for Electronics under Each Materials Management Option (MTCOzE/Short Ton)
Material
Net Source
Reduction
Emissions for
Current Mix of
Inputs3
Net
Recycling
Emissions
Net
Composting
Emissions
Net
Combustion
Emissions
Net
Landfilling
Emissions
Net
Anaerobic
Digestion
Emissions
Desktop CPUs
(20.86)
(1.49)
NA
(0.66)
0.02
(1.49)
Portable Electronic Devices
(29.83)
(1.07)
NA
0.65
0.02
(1.07)
Flat-Panel Displays
(24.19)
(1.00)
NA
0.03
0.02
(1.00)
CRT Displays
NA
(0.57)
NA
0.45
0.02
(0.57)
Electronic Peripherals
(10.32)
(0.37)
NA
2.08
0.02
(0.37)
Hard-Copy Devices
(7.65)
(0.57)
NA
1.20
0.02
(0.57)
Mixed Electronics
NA
(0.79)
NA
0.39
0.02
(0.79)
3 The current mix of inputs for electronics is considered to be 100% virgin material. Source reduction is not available as a management option
for CRT displays and mixed electronics because CRT displays are no longer manufactured and therefore their production cannot be avoided.
1-4

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1.3 RAW MATERIALS ACQUISITION AND MANUFACTURING
The wide range of different electronic products entering the waste stream every year makes it
difficult to specify the exact composition of a typical electronic product, and the technology for new
electronics continues to evolve rapidly. Electronics products can have a large amount of complexity in
design, using a wide array of materials and components. Fortunately, these materials and components
are similar across electronics products, where similar metals, plastics, display technologies, batteries and
circuit boards can be found in many common products. To streamline the process of developing life-
cycle GHG emission factors for a range of electronic products, EPA modeled the life-cycle GHG emission
factors for electronics in WARM based on the assumption that the same material components are
shared across the types of electronics in WARM. Babbitt et al. (2017) provides a detailed summary of
recent trends in U.S. electronics sales and the material make-up of these electronics. The study closely
examined 19 different products and generated mass characteristics for 12 component categories. Based
on this study, the components modeled in WARM include:
•	Ferrous metal. Ferrous metal in electronics is assumed to be composed of stamped, cold rolled
steel.
•	Aluminum. Aluminum in electronics is assumed to be composed of shape cast aluminum
components.
•	Copper. Copper in electronics is assumed to be composed primarily of copper wire.
•	Other metals. Other common metals frequently found in electronics include nickel, zinc, and tin
(Andrea et al., 2014).
•	Plastic. A wide range of plastic resins are commonly found in electronics. For the purpose of
modeling in WARM, EPA assumed that electronics contain a mix of acrylonitrile butadiene
styrene (ABS), polyethylene terephthalate (PET), polycarbonate (PC), polyamide (PA), polyvinyl
chloride (PVC), high-density polyethylene (HDPE), polypropylene (PP), polyurethane (PUR), and
epoxy (Andrea et al., 2014).
•	Printed circuit board (PCB). PCBs consist of electronic components connected via laminated
copper and non-conductive materials.
•	Flat panel display module. Flat panel display modules are composite devices typical composed of
cold cathode fluorescent lamps (CCFL) or light-emitting diodes (LED).
•	CRT glass and lead. CRT displays include a large component of panel glass and funnel glass
coated in lead.
•	Battery. Batteries used to power portable electronic devices are assumed to be predominately
lithium-ion systems (Babbitt et al., 2017).
These components are shared across the electronic materials modeled in WARM, which are
intended to be representative of electronics entering the waste stream based on units sold in the U.S.
from 1990 to 2017 (Babbitt et al., 2017). Exhibit 1-6 presents the component mass share of each
electronic material type in WARM using data from Babbitt et al. (2017) and Hikwama (2005).
Exhibit 1-6: Component Mass Share for Electronics in WARM (Babbitt et al., 2017; Hikwama, 2005)
Material
Ferrous
Metal
Aluminum
Copper
Other
Metals
Plastic
Printed
Circuit
Board
Flat Panel
Display
Module
CRT Glass
and Lead
Battery
Desktop CPUs
59%
11%
4%
0%
12%
14%
0%
0%
0%
1-5

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Material
Ferrous
Metal
Aluminum
Copper
Other
Metals
Plastic
Printed
Circuit
Board
Flat Panel
Display
Module
CRT Glass
and Lead
Battery
Portable Electronic
Devices
7%
12%
2%
4%
27%
14%
16%
0%
18%
Flat-Panel Displays
37%
7%
1%
0%
22%
6%
26%
0%
0%
CRT Displays
5%
1%
3%
0%
19%
11%
0%
61%
0%
Electronic Peripherals
2%
0%
26%
0%
68%
4%
0%
0%
0%
Hard-Copy Devices
37%
0%
1%
0%
59%
3%
0%
0%
0%
1.4 MATERIALS MANAGEMENT METHODOLOGIES
This analysis considers source reduction, recycling, landfilling, and combustion pathways for
materials management of electronics. It is important to note that electronics are not necessarily
recycled into new electronics, however; they are recycled in an open loop. The LCA of their disposal
must take into account the variety of second-generation products from recycling electronics.
Information on electronics recycling and the resulting second-generation products is sparse; however,
EPA has modeled pathways for which consistent LCA data are available for recycled electronics
components. The second-generation products considered in this analysis are: steel into scrap steel,
aluminum into scrap aluminum, copper into scrap copper, plastics into ground plastic, nickel into scrap
nickel, CRT glass into lead bullion, precious metals into scrap precious metals, and batteries into scrap
lithium cobalt oxide.
Source reduction leads to the largest reduction in GHG emissions for electronics, since
manufacturing electronics and their components is especially energy intensive. Recycling electronics
leads to greater reductions than combustion and landfilling, since it also reduces similarly energy-
intensive product manufacturing. Combustion has a positive net emission factor for most electronic
materials that is driven by the plastic content in electronics, while landfilling has a slightly positive
emission factor due to the emissions from landfill operation equipment.
1.4.1 Source Reduction
Source reduction activities reduce the number of electronics that are produced, thereby
reducing GHG emissions from electronics production. Increasing the lifetime of an electronic product
(e.g., through upgrades in software) or finding alternatives to purchasing new electronics (e.g., using a
donated product) are examples of source reduction. For more information on this practice, see the
Source Reduction chapter.
Exhibit 1-7 outlines the GHG emission factor for source reducing electronics. GHG benefits of
source reduction are calculated as the avoided emissions from raw materials acquisition and
manufacturing (RMAM) of new electronics. Source reduction is not modeled for CRT displays because
CRT displays are no longer manufactured. Similarly, source reduction is not modeled for mixed
electronics because CRT displays are a component of mixed electronics.
Exhibit 1-7. Electronics Source Reduction Emission Factor (MTC02E/Short Ton)
Material
Raw Material
Acquisition and
Manufacturing for
Current Mix of
Inputs
Raw Material
Acquisition and
Manufacturing
for 100% Virgin
Inputs
Forest Carbon
Storage for
Current Mix of
Inputs
Forest Carbon
Storage for
100% Virgin
Inputs
Net Emissions
for Current
Mix of Inputs
Net
Emissions for
100% Virgin
Inputs
Desktop
CPUs
-20.86
-20.86
NA
NA
-20.86
-20.86
1-6

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Raw Material
Raw Material





Acquisition and
Acquisition and
Forest Carbon
Forest Carbon

Net

Manufacturing for
Manufacturing
Storage for
Storage for
Net Emissions
Emissions for

Current Mix of
for 100% Virgin
Current Mix of
100% Virgin
for Current
100% Virgin
Material
Inputs
Inputs
Inputs
Inputs
Mix of Inputs
Inputs
Portable
-29.83
-29.83
NA
NA
-29.83
-29.83
Electronic






Devices






Flat-Panel
-24.19
-24.19
NA
NA
-24.19
-24.19
Displays






CRT
NA
NA
NA
NA
NA
NA
Displays






Electronic
-10.32
-10.32
NA
NA
-10.32
-10.32
Peripherals






Hard-Copy
-7.65
-7.65
NA
NA
-7.65
-7.65
Devices






Mixed
NA
NA
NA
NA
NA
NA
Electronics






Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
NA = Not applicable.
1.4.1.1 Developing the Emission Factor for Source Reduction of Electronics
To calculate the avoided GHG emissions for electronics, EPA looked at three broad sources of
GHG emissions from RMAM activities: process energy, transportation energy and non-energy GHG
emissions. Exhibit 1-8 shows the results for each broad source and the total GHG emission factor for
source reduction for each of the electronics components modeled in WARM. More information on each
component and broad emissions source making up the final emission factor is provided below.
Exhibit 1-8: Raw Material Acquisition and Manufacturing Emission Factor for Virgin Production of Electronics by
Component (MTCChE/Short Ton)	
(a)
(b)
(c)
(d)
(e)


Transportation
Process Non-
Net Emissions
Component
Process Energy
Energy
Energy
(e = b + c + d)
Ferrous Metal
2.32
IE
-
2.32
Aluminum
5.90
IE
-
5.90
Copper
6.72
0.03
-
6.76
Other Metals
4.82
IE
0.28
5.10
Plastic
4.28
0.11
0.38
4.76
Printed Circuit Board
126.70
IE
-
126.70
Flat Panel Display Module
54.59
IE
-
54.59
CRT Glass and Lead
NA
NA
NA
NA
Battery
4.79
IE
-
4.79
Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
NA = Not applicable.
IE = Included elsewhere. Process energy emissions are assumed to encompass transportation energy.
- = Zero emissions.
First, EPA obtained an estimate of the amount of energy required to produce one short ton of
each component. Next, we determined the fuel mix that comprises this Btu estimate using data from
the same sources for each component and then multiplied the fuel consumption (in Btu) by the fuel-
specific carbon contents. The sum of the resulting GHG emissions by fuel type comprises the total
process energy GHG emissions, including both C02 and CH4, from all fuel types used in electronics
production. The process energy used to produce electronic components and the resulting emissions are
presented in Exhibit 1-9, including the source for the process energy data.
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Exhibit 1-9: Process Energy GHG Emissions Calculations for Virgin Production of Electronics by Component

Process Energy per Short
Process Energy GHG
Data Source(s)

Ton Made from Virgin
Emissions (MTC02E/Short

Component
Inputs (Million Btu)
Ton)

Ferrous Metal
28.95
2.32
ANL, 2018
Aluminum
127.37
5.90
ANL, 2018
Copper
122.52
6.72
FAL, 2002
Other Metals
77.85
4.82
ANL, 2018; Ecoinvent Centre,
2015
Plastic
71.12
4.28
ANL, 2018; FAL, 2011a
Printed Circuit Board
607.07
126.70
Teehan and Kandlikar, 2013
Flat Panel Display Module
202.22
54.59
Teehan and Kandlikar, 2013
CRT Glass and Lead
NA
NA
NA
Battery
24.09
4.79
Teehan and Kandlikar, 2013
NA = Not applicable.
Transportation energy emissions come from fossil fuels used to transport component raw
materials and intermediate products. The methodology for estimating these emissions is the same as
that used for process energy emissions. Based upon an estimated total component transportation
energy in Btu, EPA calculated the total emissions using fuel-specific carbon coefficients. For several of
the components, transportation energy could be not be disaggregated from overall process energy; for
these materials EPA assumed that the process energy was inclusive of transportation energy. The
transportation energy used to produce electronic components and the resulting emissions are
presented in Exhibit 1-10, including the source for the transportation energy data.
Exhibit 1-10: Transportation Energy Emissions Calculations for Virgin Production of Electronics by Component

Transportation Energy per
Transportation Energy GHG
Data Source(s)

Short Ton Made from Virgin
Emissions (MTC02E/Short

Material
Inputs (Million Btu)
Ton)

Ferrous Metal
IE
IE
ANL, 2018
Aluminum
IE
IE
ANL, 2018
Copper
0.46
0.03
FAL, 2002
Other Metals


ANL, 2018; Ecoinvent Centre,

IE
IE
2015
Plastic
0.69
0.69
ANL, 2018; FAL, 2011a
Printed Circuit Board
IE
IE
Teehan and Kandlikar, 2013
Flat Panel Display Module
IE
IE
Teehan and Kandlikar, 2013
CRT Glass and Lead
NA
NA
NA
Battery
IE
IE
Teehan and Kandlikar, 2013
Note: The transportation energy and emissions in this exhibit do not include retail transportation.
NA = Not applicable.
IE = Included elsewhere. Process energy emissions are assumed to encompass transportation energy.
Non-energy GHG emissions occur during manufacturing but are not related to combusting fuel
for energy. For electronics, non-energy GHGs are emitted in the virgin production of plastic resins,
copper, and tin (ANL, 2018; Ecoinvent Centre, 2015; FAL, 2011a; FAL, 2002). The various data sources
provide data on GHG emissions from non-energy-related processes in units of pounds of native gas. EPA
converted pounds of gas per 1,000 lbs. of component to metric tons of gas per short ton of component
and then multiplied that by the ratio of carbon to gas to produce the emission factor in MTC02E per
short ton of component. Exhibit 1-11 shows the components for estimating process non-energy GHG
emissions for electronics.
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Exhibit 1-11: Process Non-Energy Emissions Calculations for Virgin Production of Electronics by Component
Material
co2
Emissions
(MT/Short
Ton)
ch4
Emissions
(MT/Short
Ton)
cf4
Emissions
(MT/Short
Ton)
c2f6
Emissions
(MT/Short
Ton)
n2o
Emissions
(MT/Short
Ton)
Non-Energy
Carbon
Emissions
(MTCOzE/Short
Ton)
Ferrous Metal
-
-
-
-
-
-
Aluminum
-
-
-
-
-
-
Copper
0.00
-
-
-
-
0.00
Other Metals
0.28
-
-
-
-
0.28
Plastic
0.20
0.01
-
-
0.00
0.38
Printed Circuit Board
-
-
-
-
-
-
Flat Panel Display
Module
-
-
-
-
-
-
CRT Glass and Lead
NA
NA
NA
NA
NA
NA
Battery
-
-
-
-
-
-
- = Zero emissions.
1.4.2 Recycling
According to EPA (2015), 40 percent of consumer electronics were recycled in 2015. EPA and
other organizations are focused on improving the recycling of electronics because of several factors: (1)
rapid sales growth and change are generating a growing stream of obsolete products, (2) manufacturing
electronics consumes large amounts of energy and materials, (3) electronics contain toxic substances,
and (4) convenient and widespread systems for collecting and recycling electronics are not yet fully
established. This section describes the development of the emission factor, which is shown in the final
column of Exhibit 1-12. For more information on recycling in general, please see the Recycling chapter.
Exhibit 1-12: Recycling Emission Factor for PCs MTCOzE/Short Ton)

Raw Material

Recycled

Recycled



Acquisition and

Input
Recycled Input
Input

Net

Manufacturing
Materials
Credit3
Credit3 -
Credit3 -
Forest
Emissions

(Current Mix of
Management
Process
Transportation
Process
Carbon
(Post-
Material
Inputs)
Emissions
Energy
Energy
Non-Energy
Storage
Consumer)
Desktop







CPUs
-
0.01
-1.47
0.01
-0.04
-
-1.49
Portable







Electronic







Devices
-
0.02
-1.14
0.01
0.04
-
-1.07
Flat-panel







Displays
-
0.02
-1.01
0.01
-0.02
-
-1.00
CRT Displays
-
0.02
-0.56
0.00
-0.04
-
-0.57
Electronic







Peripherals
-
0.02
-0.39
0.02
-0.03
-
-0.37
Hard-copy







Devices
-
0.02
-0.56
0.00
-0.03
-
-0.57
Mixed







Electronics
-
0.02
-0.79
0.01
-0.03
-
-0.79
Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
3 Includes emissions from the virgin production of secondary materials
WARM models electronics as being recycled in an open loop into the following secondary
materials: steel sheet, aluminum sheet, copper wire, post-consumer HDPE and PET plastics, post-
consumer nickel, lead bullion, post-consumer precious metals, and lithium cobalt oxide (Exhibit 1-13).
1-9

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Exhibit 1-13: Fate of Recycled Electronics
Primary Component from Recycled
Electronics
Secondary Product from Recycled
Electronics
Data Source(s)
Ferrous metal
Steel sheet
ANL, 2018; Vanegas et al., 2017
Aluminum
Aluminum sheet
ANL, 2018; Vanegas et al., 2017
Copper
Copper wire
FAL, 2002; Bigum et al 2012.
Other metals
Nickel
ANL, 2018; Bigum et al 2012.
Plastic
HDPE
FAL, 2011a; FAL, 2011b
PET
FAL, 2011a; FAL, 2011b
Printed circuit board
Steel sheet
ANL, 2018; Vanegas et al., 2017
Aluminum sheet
ANL, 2018; Vanegas et al., 2017
Copper wire
FAL, 2002; Vanegas et al., 2017
Precious metals (gold, silver, and
palladium)
Ecoinvent Centre, 2015; Bigum et al
2012.
Flat panel display module
Aluminum sheet
ANL, 2018; Vanegas et al., 2017
Copper wire
FAL, 2002; Vanegas et al., 2017
CRT glass and lead
Lead bullion
ANL, 2018; Turner et al., 2015
Battery
Lithium cobalt oxide
ANL, 2018; Dewulf et al., 2010
The materials management emissions shown in Exhibit 1-12 include all of the GHG emissions
associated with collecting, transporting, and processing electronics at end of life. The recycled input
credits includes all of the GHG emissions associated with recycling or remanufacturing electronics into
secondary materials. None of the upstream GHG emissions from manufacturing the electronics in the
first place are included; instead, WARM calculates a "recycled input credit" by assuming that the
recycled material avoids—or offsets—the GHG emissions associated with producing the same amount of
secondary materials from virgin inputs. Because electronics do not contain any wood products, there are
no recycling benefits associated with forest carbon sequestration. The GHG benefits from the recycled
input credits are discussed in greater detail below.
1.4.2.1 Developing the Emission Factor for Recycling of Electronics
EPA calculated the GHG benefits of recycling electronics by comparing the difference between
the emissions associated with manufacturing a short ton of each of the secondary products from
recycled electronic components and the emissions from manufacturing the same ton from virgin
materials, after accounting for losses that occur in the recycling process. These results were then
weighted by the component mass share in Exhibit 1-6 to obtain a composite emission factor for
recycling one short ton of each electronics material. This recycled input credit is composed of GHG
emissions from process energy, transportation energy and process non-energy.
To calculate each component of the recycling emission factor, EPA followed six steps, which are
described in detail below.
Step 1. Calculate emissions from virgin production of one short ton of secondary product. EPA
applied fuel-specific carbon coefficients to the data for virgin RMAM of each secondary product based
on data from the sources cited in Exhibit 1-13. This estimate was then summed with the emissions from
transportation and process non-energy emissions to calculate the total emissions from virgin production
of each secondary product. The calculations for virgin process, transportation and process non-energy
emissions for the secondary products are presented in Exhibit 1-14, Exhibit 1-15 and Exhibit 1-16,
respectively.
1-10

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Exhibit 1-14: Process Energy GHG Emissions Calculations for Virgin Production of Electronics Secondary Products
Material
Process Energy per Short Ton Made
from Virgin Inputs (Million Btu)
Process Energy GHG Emissions
(MTC02E/Short Ton)
Steel
28.95
2.32
Aluminum
127.37
5.90
Copper
122.52
6.72
Nickel
111.97
6.88
HDPE
23.59
1.13
PET
28.06
1.72
Gold
59,843.50
3,970.29
Silver
2,136.28
122.02
Palladium
25,675.12
1,746.35
Lead
23.08
2.03
Lithium cobalt oxide
32.11
1.76
Exhibit 1-15: Transportation Energy Emissions Calculations for Virgin Production of Electronics Secondary
Products
Material
Transportation Energy per Short Ton
Made from Virgin Inputs (Million
Btu)
Transportation Energy GHG
Emissions (MTC02E/Short Ton)
Steel
IE
IE
Aluminum
IE
IE
Copper
0.46
0.03
Nickel
IE
IE
HDPE
2.74
0.15
PET
1.00
0.07
Gold
IE
IE
Silver
IE
IE
Palladium
IE
IE
Lead
IE
IE
Lithium cobalt oxide
IE
IE
Note: The transportation energy and emissions in this exhibit do not include retail transportation
IE = Included elsewhere. Process energy emissions are assumed to encompass transportation energy.
Exhibit 1-16: Process Non-Energy Emissions Calculations for Virgin Production of Electronics Secondary Products

co2
ch4
cf4
c2f6
n2o
Non-Energy

Emissions
Emissions
Emissions
Emissions
Emissions
Carbon Emissions

(MT/Short
(MT/Short
(MT/Short
(MT/Short
(MT/Short
(MTC02E/Short
Material
Ton)
Ton)
Ton)
Ton)
Ton)
Ton)
Steel
-
-
-
-
-
-
Aluminum
-
-
-
-
-
-
Copper
0.00
-
-
-
-
0.00
Nickel
-
-
-
-
-
-
HDPE
0.06
0.01
-
-
-
0.20
PET
0.27
0.00
-
-
-
0.39
Gold
700.12
-
-
-
-
700.12
Silver
30.78
-
-
-
-
30.78
Palladium
258.27
-
-
-
-
258.27
Lead
-
0.00
-
-
-
0.09
Lithium cobalt oxide
-
-
-
-
-
-
- = Zero emissions.
Step 2. Calculate GHG emissions for recycled production of one short ton of the secondary
product. EPA then applied the same carbon coefficients to the energy data for the production of the
secondary products from recycled electronics, and calculates non-energy process GHGs by converting
1-11

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data found in the sources cited in Exhibit 1-13 to metric tons of gas per short ton of secondary product.
Exhibit 1-17, Exhibit 1-18 and Exhibit 1-19 present the results for secondary product process energy
emissions, transportation energy emissions and process non-energy emissions, respectively.
Exhibit 1-17: Process Energy GHG Emissions Calculations for Recycled Production of Electronics Secondary
Products
Material
Process Energy per Short Ton Made
from Recycled Inputs (Million Btu)
Energy Emissions (MTC02E/Short
Ton)
Steel
18.07
1.12
Aluminum
26.37
1.38
Copper
101.05
5.34
Nickel
19.28
1.20
HDPE
5.19
0.31
PET
11.77
0.69
Precious metals (gold, silver, and palladium)
9.17
0.58
Lead
4.23
0.40
Lithium cobalt oxide
5.31
0.29
Exhibit 1-18: Transportation Energy GHG Emissions Calculations for Recycled Production of Electronics
Secondary Products
Material
Transportation Energy per Ton
Made from Recycled Inputs (Million
Btu)
Transportation Emissions
(MTC02E/Short Ton)
Steel
IE
IE
Aluminum
IE
IE
Copper
2.17
0.16
Nickel
IE
IE
HDPE
2.31
0.17
PET
2.60
0.19
Precious metals (gold, silver, and palladium)
IE
IE
Lead
IE
IE
Lithium cobalt oxide
IE
IE
Note: The transportation energy and emissions in this exhibit do not include retail transportation
IE = Included elsewhere. Process energy emissions are assumed to encompass transportation energy.
Exhibit 1-19: Process Non-Energy Emissions Calculations for Recycled Production of Electronics Secondary
Products






Non-Energy

co2
ch4

c2f6
n2o
Carbon

Emissions
Emissions
CF4 Emissions
Emissions
Emissions
Emissions

(MT/Short
(MT/Short
(MT/Short
(MT/Short
(MT/Short
(MTC02E/Sh
Material
Ton)
Ton)
Ton)
Ton)
Ton)
ortTon)
Steel
-
-
-
-
-
-
Aluminum
-
-
-
-
-
-
Copper
0.00
-
-
-
-
0.00
Nickel
-
-
-
-
-
-
HDPE
-
-
-
-
-
-
PET
-
-
-
-
-
-
Precious metals (gold,






silver, and palladium)
-
-
-
-
-
-
Lead
-
-
-
-
-
-
Lithium cobalt oxide
1.49
-
-
-
-
1.49
- = Zero emissions.
1-12

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Step 3. Account for recycling losses. In the case of electronics, data indicated that the recovery
rate varies by component. EPA assumed that the portion of electronics components not recovered for
recycling were landfilled. Exhibit 1-20 shows the recovery rates for each electronics component based
on data found in the sources cited in Exhibit 1-13.
Exhibit 1-20: Recovery Rates for Electronics Components Recycled into Secondary Products
Primary Component from
Recycled Electronics
Secondary Product from Recycled
Electronics
Short Tons Product Made per Short
Ton Component Recycled
Ferrous metal
Steel sheet
95.00%
Aluminum
Aluminum sheet
87.00%
Copper
Copper wire
57.00%
Other metals
Nickel
28.94%
Plastic
HDPE
9.03%
PET
3.12%
Printed circuit board
Steel sheet
20.34%
Aluminum sheet
3.60%
Copper wire
11.91%
Precious metals (gold, silver, and palladium)
0.14%
Flat panel display module
Aluminum sheet
0.66%
Copper wire
35.92%
CRT glass and lead
Lead bullion
17.60%
Battery
Lithium cobalt oxide
33.47%
Step 4. Calculate the difference in emissions between virgin and recycled production. EPA then
subtracted the recycled product emissions (Step 2) from the virgin product emissions (Step 1) and
multiplied by the recovery rate (Step 3) to get the GHG savings. These results are shown in Exhibit 1-21.
The differences in emissions from process energy, transportation energy and non-energy processing
were then adjusted to account for the loss rates by multiplying the final three columns of Exhibit 1-21 by
the retention rates in column (d) of Exhibit 1-20.
Exhibit 1-21: Differences in Emissions between Recycled and Virgin Electronics Secondary Products Manufacture
MTCChE/Short Ton)	
Primary
Component
Secondary
Product
Product Manufacture Using
100% Virgin Inputs
(MTCOzE/Short Ton)
Product Manufacture Using
100% Recycled Inputs
(MTC02E/Short Ton)
Difference Between Recycled
and Virgin Manufacture
(MTC02E/Short Ton)
Process
Energy
Transpor
-tation
Energy
Process
Non-
Energy
Process
Energy
Transpor
-tation
Energy
Process
Non-
Energy
Process
Energy
Transpor
-tation
Energy
Process
Non-
Energy
Ferrous
metal
Steel sheet
2.32
-
-
1.12
-
-
-1.14
-
-
Aluminum
Aluminum
sheet
5.90
-
-
1.38
-
-
-3.93
-
-
Copper
Copper wire
6.72
0.03
0.00
5.34
0.16
0.00
-0.79
0.07
-
Other
metals
Nickel
6.88
-
-
1.20
-
-
-1.64
-
-
Plastic
HDPE
0.06
0.00
0.01
0.02
0.01
-
-0.03
0.00
-0.01
PET
0.12
0.02
0.02
0.03
0.02
-
-0.07
0.00
-0.02
Printed
circuit board
Steel sheet
0.47
-
-
0.23
-
-
-0.25
-
-
Aluminum
sheet
0.21


0.05


-0.16

-
1-13

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Product Manufacture Using
Product Manufacture Using
Difference Between Recycled


100% Virgin Inputs
100% Recycled Inputs
and Virgin Manufacture


(MTCOzE/Short Ton)
(MTC02E/Short Ton)
(MTC02E/Short Ton)



Transpor
Process

Transpor
Process

Transpor
Process
Primary
Secondary
Process
-tation
Non-
Process
-tation
Non-
Process
-tation
Non-
Component
Product
Energy
Energy
Energy
Energy
Energy
Energy
Energy
Energy
Energy

Copper wire
0.80
0.00
0.00
0.64
0.02
0.00
-0.16
0.01
-

Precious
2.23

0.34
0.58
_
0.07
-1.65

-0.27

metals (gold,










silver, and










palladium)









Flat panel
Aluminum
0.04


0.01
_

-0.03

_
display
sheet









module
Copper wire
2.42

::::::
1.92
0.06
::::::
-0.50
:::v:
-
CRT glass
Lead bullion
0.36

0.02
0.07

_
-0.29

-0.02
and lead










Battery
Lithium cobalt
oxide
0.59


0.10

0.50
-0.49

0.50
Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
Totals may not sum due to independent rounding.
- = Zero emissions.
Step 5. Weight the results by the percentage of recycled electronics that the component makes
up. Using the percentages provided in Exhibit 1-6, EPA weighted the individual GHG differences from
Step 4 for each of the components in a given electronics material. Each product's process energy,
transportation energy and process non-energy emissions were weighted by the percentages in Exhibit
1-6 and then summed as shown in the final column of Exhibit 1-22.
Exhibit 1-22: Electronics Recycling Emission Factors (MTCOzE/Short Ton)

Recycled Input Credit for Recycling One Short Ton of Electronics

Weighted Process
Weighted
Weighted Process


Energy
Transport Energy
Non-Energy
Total (MTCOzE/Short

(MTCOzE/Short Ton
(MTCOzE/Short Ton
(MTCOzE/Short Ton of
Ton of Electronics
Material
of Each Material)
of Each Material)
Each Material)
Recycled)
Desktop CPUs
-1.47
0.01
-0.04
-1.50
Portable




Electronic




Devices
-1.14
0.01
0.04
-1.09
Flat-panel




Displays
-1.01
0.01
-0.02
-1.01
CRT Displays
-0.56
0.00
-0.04
-0.60
Electronic




Peripherals
-0.39
0.02
-0.03
-0.40
Hard-copy




Devices
-0.56
0.00
-0.03
-0.59
Mixed




Electronics
-0.79
0.01
-0.03
-0.81
Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
NA = Not applicable.
Totals may not sum due to independent rounding.
Step 6. Factor in materials management emissions for process emissions from demanufacturing
electronics and landfilling unrecovered materials. EPA assumed that electronics are shredded to extract
the materials that are recycled into secondary products. The act of shredding electronics consumes
electricity, and the GHG emissions associated with this electricity use are allocated to the total emission
factor for recycling one short ton of electronics (Bigum et al2012). The unrecovered materials are
1-14

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landfilled, resulting in process and transportation energy emissions as described in Section 1.4.5. The
final electronics recycling emission factor is the sum of the weighted secondary products' emission
factors from Exhibit 1-22 and the process emissions from demanufacturing electronics and landfilling
unrecovered materials as shown in Exhibit 1-23.
Exhibit 1-23: Calculation of Recycling Emission Factor for Electronics



Total Waste


Demanufacturing
Landfilling Process and
Management
Net Recycling

Process Energy
Transportation Energy
Emissions
Emissions
Material
(MTCOzE/Short Ton)
(MTC02E/Short Ton)
(MTC02E/Short Ton)
(MTCOzE/Short Ton)
Desktop CPUs
0.01
0.00
0.01
-1.49
Portable Electronic
0.01
0.01
0.02

Devices



-1.07
Flat-panel Displays
0.01
0.01
0.02
-1.00
CRT Displays
0.01
0.01
0.02
-0.57
Electronic Peripherals
0.01
0.01
0.02
-0.37
Hard-copy Devices
0.01
0.01
0.02
-0.57
Mixed Electronics
0.01
0.01
0.02
-0.79
Totals may not sum due to independent rounding.
1.4.3	Composting
Because electronics are not subject to aerobic bacterial degradation, they cannot be composted.
Therefore, WARM does not consider GHG emissions or storage associated with composting.
1.4.4	Combustion
GHG emissions from combusting electronics result from the combustion process as well as from
indirect emissions from transporting electronics to the combustor. Combustion also produces energy
that can be recovered to offset electricity and GHG emissions that would have otherwise been produced
from non-baseload power plants feeding into the national electricity grid. Finally, most waste-to-energy
(WTE) plants recycle steel that is left after combustion, which offsets the production of steel from other
virgin and recycled inputs. All of these components make up the combustion factors calculated for
electronics.
It is likely that very few whole electronics are combusted, since components of electronics can
interfere with the combustion process and the combustion of CRT monitors in particular can deposit
lead that exceeds permitted levels in the combustion ash. Consequently, some level of disassembly and
sorting is likely required to separate combustible plastics from other electronic components (EPA, 2008;
FAL, 2002), although this is not included in WARM'S combustion modeling approach. WARM accounts
for the GHG emission implications of combusting electronics, but material managers should ensure that
electronics are appropriately processed and sorted before sending the components to combustors.
For further information, see the Combustion chapter. Because WARM'S analysis begins with
materials at end of life, emissions from RMAM are zero. Exhibit 1-24 shows the components of the
emission factor for combustion of electronics. Further discussion on the development of each piece of
the emission factor is provided below.
1-15

-------
Exhibit 1-24: Components of the Combustion Net Emission Factor for Electronics (MTCOzE/Short Ton)

Raw Material







Acquisition







and





Net

Manufacturing





Emissions

(Current Mix
Transportation
C02 from
N20 from
Utility
Steel
(Post-
Material
of Inputs)
to Combustion
Combustion
Combustion
Emissions
Recovery
Consumer)
Desktop CPUs
-
0.01
0.40
-
-0.12
-0.95
-0.66
Portable







Electronic Devices
-
0.01
0.88
-
-0.12
-0.12
0.65
Flat-panel Displays
-
0.01
0.73
-
-0.12
-0.60
0.03
CRT Displays
-
0.01
0.63
-
-0.12
-0.08
0.45
Electronic







Peripherals
-
0.01
2.22
-
-0.12
-0.03
2.08
Hard-copy Devices
-
0.01
1.91
-
-0.12
-0.60
1.20
Mixed Electronics
-
0.01
0.86
-
-0.12
-0.37
0.39
Note: Negative values denote net GHG emission reductions or carbon storage from a materials management practice.
1.4.4.1 Developing the Emission Factor for Combustion of Electronics
EPA estimated that electronics have a carbon content ranging from 12 percent to 68 percent,
depending on the material type. This carbon is contained within the plastics in electronics. EPA also
assumed that 98 percent of that carbon is converted to C02 during combustion. The resulting direct C02
emissions from combustion of carbon in electronics are presented in Exhibit 1-25.
Exhibit 1-25: Electronics Combustion CO2 Emission Factor Calculation (MTCOzE/Short Ton)
Material
Non-Biomass
Carbon
Content
Carbon Converted
to C02 during
Combustion
Combustion C02
Emissions
(MTCOzE/Short Ton)
Desktop CPUs
12%
98%
0.40
Portable Electronic Devices
27%
98%
0.88
Flat-panel Displays
22%
98%
0.73
CRT Displays
20%
98%
0.63
Electronic Peripherals
68%
98%
2.22
Hard-copy Devices
59%
98%
1.91
Mixed Electronics
27%
98%
0.86
EPA estimated C02 emissions from transporting electronics to the WTE plant and transporting
ash from the WTE plant to the landfill using data provided by FAL.
Most utility power plants use fossil fuels to produce electricity, and the electricity produced at a
WTE plant reduces the demand for fossil-derived electricity. As a result, the combustion emission factor
for electronics includes avoided GHG emissions from utilities. EPA calculated the avoided utility C02
emissions based on the energy content of the plastics within electronics; the combustion efficiency of
the WTE plant, including transmission and distribution losses; and the national average carbon-intensity
of electricity produced by non-baseload power plants. Exhibit 1-26 shows utility offsets from electronics
combustion.
1-16

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Exhibit 1-26: Utility GHG Emissions Offset from Combustion of Electronics
(a)
(b)
(c)
(d)
(e)


Combustion
Emission Factor for Utility-
Avoided Utility GHG per

Energy Content
System
Generated Electricity (MTC02E/
Short Ton Combusted

(Million Btu per
Efficiency
Million Btu of Electricity
(MTC02E/Short Ton)
Material
Short Ton)
(%)
Delivered)
(e = b x c x d)
Desktop CPUs
3.07
17.8%
0.21
0.12
Portable Electronic Devices
3.07
17.8%
0.21
0.12
Flat-panel Displays
3.07
17.8%
0.21
0.12
CRT Displays
3.07
17.8%
0.21
0.12
Electronic Peripherals
3.07
17.8%
0.21
0.12
Hard-copy Devices
3.07
17.8%
0.21
0.12
Mixed Electronics
3.07
17.8%
0.21
0.12
The combustion of electronics at WTE facilities also includes steel recovery and recycling
processes. Approximately 90 percent of combustion facilities have ferrous recovery systems. The steel
content of electronics varies by material. Since some of this steel is lost during combustion, we included
a ferrous recovery factor of 98 percent. The emission impacts of recycling of this recovered steel are
shown in Exhibit 1-27.
Exhibit 1-27: Steel Production GHG Emissions Offset from Steel Recovered from Combustion of Electronics
Material
Short Tons of Steel
Recovered per Short Ton
of Waste Combusted
Avoided C02 Emissions per Ton
of Steel Recovered
(MTC02E/Short Ton)
Avoided C02 Emissions per
Ton of Waste Combusted
(MTC02E/Short Ton)
Desktop CPUs
0.52
1.83
0.95
Portable Electronic Devices
0.06
1.83
0.12
Flat-panel Displays
0.33
1.83
0.60
CRT Displays
0.04
1.83
0.08
Electronic Peripherals
0.02
1.83
0.03
Hard-copy Devices
0.33
1.83
0.60
Mixed Electronics
0.20
1.83
0.37
1.4.5 Landfilling
1.4.5.1 Overview and Developing the Emission Factor for Landfilling of Electronics
In WARM, landfill emissions comprise landfill CH4 and C02 from transportation and landfill
equipment. WARM also accounts for landfill carbon storage, and avoided utility emissions from landfill
gas-to-energy recovery. However, since electronics are inorganic and do not contain biogenic carbon,
there are zero emissions from landfill CH4, zero landfill carbon storage, and zero avoided utility
emissions associated with landfilling electronics, as shown in Exhibit 1-28. Greenhouse gas emissions
associated with RMAM are not included in WARM'S landfilling emission factors. As a result, the emission
factor for landfilling electronics represents only the emissions associated with collecting the waste and
operating the landfill equipment. For more information, refer to the Landfilling chapter.
Exhibit 1-28: Landfilling Emission Factor for Electronics (MTCOzE/Short Ton)

Raw Material






Acquisition and


Avoided C02



Manufacturing


Emissions
Landfill
Net Emissions

(Current Mix of
Transportation
Landfill
from Energy
Carbon
(Post-
Material
Inputs)
to Landfill
ch4
Recovery
Storage
Consumer)
Desktop CPUs
-
0.02
-
-
-
0.02
1-17

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Material
Raw Material
Acquisition and
Manufacturing
(Current Mix of
Inputs)
Transportation
to Landfill
Landfill
ch4
Avoided C02
Emissions
from Energy
Recovery
Landfill
Carbon
Storage
Net Emissions
(Post-
Consumer)
Portable Electronic
Devices

0.02



0.02
Flat-panel Displays
-
0.02
-
-
-
0.02
CRT Displays
-
0.02
-
-
-
0.02
Electronic Peripherals
-
0.02
-
-
-
0.02
Hard-copy Devices
-
0.02
-
-
-
0.02
Mixed Electronics
-
0.02
-
-
-
0.02
NA = Not applicable.
- = Zero emissions.
1.4.6 Anaerobic Digestion
Because of the nature of electronic components, electronics cannot be anaerobically digested,
and thus, WARM does not include an emission factor for the anaerobic digestion of electronics.
1.5 LIMITATIONS
There are several limitations to this analysis, which is based on several assumptions from expert
judgment. The limitations associated with the source reduction and recycling emission factors include:
•	The primary source for characterizing the components of electronics (Babbitt et al., 2017)
provides a recent, comprehensive data set for electronic product material make-up. However,
the authors aggregated component data into a select number of component types, with several
products having a mass percentage listed as "uncategorized". Based on discussions with the
authors, EPA assumed excluded the "uncategorized" mass percentage and scaled-up the
remaining component mass percentages to account for the complete product mass.
•	Whenever possible, EPA used the most recent, comprehensive and relevant LCI data in
developing the source reduction and recycling emission factors. However, product design and
recycling practices can vary across electronics materials and components, and there can be
inaccuracies when using a limited set of component-specific data sources and assumptions that
often do not account for these variations.
•	The open-loop recycling process has several limitations, including limited availability of
representative life-cycle data for electronics and the materials recovered from them as well as
the high variability in electronics recycling practices in the United States.
•	Data sources used in modeling source reduction and recycling of electronics often do not
distinguish between process energy (e.g., fossil fuels combusted on-site during production) and
transportation energy (i.e., fuel used to transport raw materials to manufacturing facilities).
Where transport energy was not disaggregated in the underlying data sources, EPA assumed it
was included as part of the process energy.
•	Recycling rates can have a significant impact when estimating the energy and GHG emission
impacts of recycling operations. EPA sought to apply the most recent and relevant recycling
rates from available literature, but these rates may not reflect variations across different
recycling systems, programs, and technologies.
1-18

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•	Existing literature indicates that lithium-ion batteries have been used in the majority of portable
electronics for several years, largely replacing nickel-based batteries (Deng 2015). EPA was
unable to locate available data from the literature that quantitatively documented the share of
battery types currently entering the waste stream; however, EPA (2016a) estimates of average
product lifespan suggest that there should be a minimal number of products relying on nickel-
based batteries still in circulation, limiting the impact of these batteries on overall battery
modeling results. Based on this understanding, EPA limited the modeling for source reduction
and recycling to lithium-ion batteries.
•	The electronics updates in WARM Version 15 do not include the addition of a separate
management practice for product reuse. EPA may consider including the addition of a reuse
pathway for electronics and other materials (e.g., food donation, C&D material reuse) as part of
future WARM updates using a consistent methodology and assumptions. To address reuse in
the near term, EPA my consider addressing reuse through updates to the existing "Modeling
Reuse in EPA's Waste Reduction Model" guidance document, which suggests ways that the
source reduction pathway can be used as a proxy for reuse.
•	EPA has not conducted a comprehensive analysis of the degree to which the electronics
materials modeled in WARM can serve as reasonable proxies for other electronics not modeled
in WARM. However, some preliminary, high-level review by EPA indicates that the following
reasonable proxies
o Video game consoles can be modeled using the Desktop CPUs material
o Audio/video players (i.e., VCRs, DVD players, and Blu-Ray players) can be modeled using
the Mixed Electronics material
o Digital cameras can be modeled using the Portable Electronic Devices material
1.6 REFERENCES
Andrea, A.S.G. and Vaija, M.S. (2014). To Which Degree Does Sector Specific Standardization Make Life
Cycle Assessments Comparable?—The Case of Global Warming Potential of Smartphones.
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