Measuring Emissions for Consumer Devices

Overview of Emissions by Device

This graphic, from Malmodin and Lundén, is a useful overview of emissions from production vs use phase. Note that the numbers here are slightly different than the aggregated conclusions we draw below. Footprint by device

Calculating Lifecycle Emissions Per Second of Use

The Lifecycle Annual Footprint (LAF) of a particular device, per Belkhir and Elmeligi, is the Use Phase Energy (UPE) plus the Production Energy (PE) divided by the Useful Life (UL). In other words, “the Lifecycle Annual Footprint accounts for the annual footprint of both the use phase as well as the production energy, depreciating the production energy over the useful lifetime of the device. LAF = (UPE + PE) / UL Production is done around the world, not where consumer use occurs, whereas we need to calculate the UPE based on the consumer’s grid mix. We calculate Production Energy per Use Second (PEPS) using the daily usage in hours (DU): PEPS = PE / (365 • UL • DU • 3600) To calculate the Lifecycle Emissions Per Second of Use (LEPS), we multiply the grid intensity of the consumer’s location (GI) and the usage energy of the consumer device (UEPS) and add this to the production energy per second (PEPS). LEPS = PEPS + GI • UEPS The following sections outline the sources and assumptions used to calculate these metrics for various device types.

Personal Computer

From Negaoctet:
DeviceLifetime impact excluding use (kgCO2e)Description
Desktop277Desktop; personal use; average configuration: 1 CPU, 10 GB RAM, 1173 GB HDD, 442 GB SSD, mix of integrated or separated graphic card, 6 years lifespan; RAS
Laptop175Laptop; use mix, personal use; average configuration: 14,6 inches screen, 1 CPU, 11 GB RAM, 497 GB SSD, 5 years lifespan; RAS
Monitor69Computer monitors; use mix, personal and professional use; average dimension (24 inches) and technology (98.6% LCD, 1.4% OLED), 6,6 years lifespan; RAS
From Urban et al:
DeviceInstalled base (M)Power Draw (w)Usage (h/day)
Desktop7259 (idle), 85 (active)4.6 (idle), 4.8 (active)
Laptop12211 (idle), 22 (active)3.0 (idle), 3.7 (active)
Monitor101305.5
Since we do not know the exact device a consumer is using (most reporting is aggregated to device type), we use install base to create a synthetic “personal computer”. See PC emissions model. Based on this analysis, a personal computer uses an average of 53.2 W of energy while in use, and has Production Energy of 0.005 gCO2e per second of use. Visual representation of the PC emissions model

Tablet

From Negaoctet, a “Tablet; use mix, personal or professional use; average configuration: 10.44 inches screen mix of LCD screen, 4 GB RAM, 121 GB memory, 3 years lifespan; RAS” has 25.3 kgCO2e per year of embodied emissions. We don’t have a stat on daily usage of tablets. Assuming that people use them in lieu of a laptop, taking the laptop number of 6.7 hours a day. This yields a PEPS of 0.00287 gCO2e/s. For energy use, iBatteryLife compares multiple iPad models and battery life is around 10 hours for each. The average iPad, per Sir Apfelot, has around 30 Wh of battery capacity. Thus, a tablet has an average power draw of 3W.

Smartphone

From Negaoctet, a “smartphone; use mix, personal use; average configuration: 6,61 inches screen mix of LCD and OLED technologies, 7,3 GB RAM, 180 GB memory, 2,5 years lifespan; RAS” has 33.6 kgCO2e per year of embodied emissions. The typical person uses her phone for 4 hours and 23 minutes a day per Statista. This yields a PEPS of 0.0058 gCO2e/s. (Note: SRI uses a 3 hrs/day number) As an example, per GSM Arena, the Apple iPhone 13 takes 16 hours and 8 minutes to run out of battery when browsing the internet (similar to video playback). In idle mode, it takes 174 hours to discharge. It has 12.41Wh of battery capacity per Macworld. Thus, the iphone consumes 0.77W when active, and 0.071W when idle.

Television

From Urban et al:
DeviceInstalled base (M)Power Draw (w)Usage (h/day)
Television284743.9
STB: Non-DVR1132211.7
STB: DVR541311.7
STB: Thin Client33711.7
STB: DTA Adapter31524
Sound Bar2014 (active) 9 (idle)4.4 (active) 5.7 (idle)
We combine these using install base to create a synthetic “TV System” that represents the full power draw of the consumer setup. The weighted power draw of a typical setup is 87.4 watts. From the Negaoctet database, the production emissions from a 45” television (98.6% LCD, 1.4% OLED) are 45 kgCO2e per year over an 8 year useful life. Based on the above Urban data, 58.8% of TVs have set top boxes. From the Negaoctet data, the production emissions from a set top box are 7.22 kgCO2e per year for a “Modem; use mix, personal and professional use; xDSL, FTTx, 5 years lifespan; RAS” Based on 3.9 hours/day of usage, the embodied emissions from a TV and set top box are 0.0096 gCO2e/s. A detailed study of many TV models can be found at ecocostsavings.com, indicating that the average power draw of a TV in the US is 59W active, 0.5W standby. This data is not tied to a scientific study but does indicate that overall power usage may have declined since the Urban study above.

Smart Speaker

From a NRDC report by Horowitz, Hardy, and Tian:
DeviceInstalled base (M)Power draw (W)Usage (h/day)
Google Home Mini41.73.5
Amazon Echo (2nd gen)352.43.5
Google Home82.23.5
Apple HomePod35.93.5
The weighted power draw of a typical smart speaker is 2.5 watts. Assuming a use life of 3 years for a smart speaker (similar to a tablet) and 84 kgCO2e of impact from (Amazon Echo Dot LCA) and 3.5 hours/day of usage, the embodied emissions from a smart speaker are 0.0061 gCO2e/s.

Radio

Since we do not have deterministic data on the devices used to listen to a given radio spot, we define a “synthetic Radio system” representative of the average listener. Similar to the Television device, we calculate the average use and embodied impacts for each type of receiver and combine this with a usage distribution to get a representative number. Below, we detail our assumptions and sources for each component of the calculation.

Device lifespan

Studies / SourceCar Audio (years)Portable Receiver (years)Hi-Fi (years)Alarm Clock Radio & Docking Station (years)
ADEME ARCEP - France (2024)10555
ACEA - Europe (2022)12.3
Bureau of Transportation Statistics - USA (2024)14
Department for Transport & Ricardo - UK (2024)14
FordAV - Global (N/A)10+
WW Assumption105105

Daily Usage

Studies / SourceCar Audio (hours per day)Portable Receiver (hours per day)Hi-Fi (hours per day)Alarm Clock Radio & Docking Station (hours per day)
ADEME ARCEP - France (2024)0.75222
ICT Impact - Europe (2020)222
EBU Audio in Cars - Europe (2022)0.5
Rajar All Radio Listening - UK (2024)0.73 (20.5 hours per week, 25% in car)
Edison Research Share of Ear - USA (2022)0.6 (1 hour and 3 min daily audio in car from which 59% is AM/FM)
WW Assumption0.75222

Embodied Emissions

Studies / SourceCar Audio (kgCO2e)Portable Receiver (kgCO2e)Hi-Fi (kgCO2e)Alarm Clock Radio & Docking Station (kgCO2e)
Derived from ADEME ARCEP LCAs3.62E+011.66E+013.62E+011.66E+01
WW Assumption3.62E+011.66E+013.62E+011.66E+01

Use Emissions

Energy Consumption and Electricity SourceCar Audio (W)Portable Receiver (W)Hi-Fi (W)Alarm Clock Radio & Docking Station (W)
ADEME ARCEP - France (2024)38 (diesel)4.8 (grid)38 (grid)4.8 (grid)
Intertek - UK (2013)4.69 (grid)
WW Assumption38 (diesel) - conservative4.8 (grid)38 (grid)4.8 (grid)
For the usage phase of Car Audio, we use the ADEME ARCEP approach considering the power consumption of a car radio to be equal to that of Hi-Fi systems, at 38 Wh/h. Using a thermal engine efficiency of 40%, an alternator efficiency of 80%, and an energy content of 8.9 kWh per liter of fuel, the volume of fuel required for the operation of the car radio over a given period of time is calculated. We use an average Diesel oil combustion emission factors (2.7 kgCO2e/l) based on several sources: We calculate that supplying 38W of electricity requires 118.75W from a diesel car engine: (38(W) / 0.8 (alternator) / 0.4 (thermal engine)).
  • Converted in liters of diesel: 118.75 / 8900 = 0.0133 liter.
  • Converted in GHG emissions: 0.0133 * 2.7 = 0.036 kgCO2e per hour.

Linear Radio Consumption Distribution by Device

MarketCar AudioPortable ReceiverHi-FiAlarm Clock Radio & Docking StationSource
FR43%22%17.5%17.5%ADEME ARCEP p.111 Sankey Diagram
USdominant (50-60%)Edison Research - Share of Ear
UK62%Ofcom Audio Survey 2025 (p93) indicates share of ears by location
AU~40+%GfK Australian Share of Audio 2022 p.20
WW Suggestion50%25%12.5%12.5%

Synthetic Radio Device Profile

DeviceLifespan (years)Daily Usage (hours)Total HoursTotal Embodied Emissions (kgCO2e)Embodied Emissions per s (gCO2e)Energy consumption per s (W)Use Emissions per s (gCO2e)Distribution
Car Audio.100.752700 (103600.75)3,62E+013,72E-03 (3,62E+01 / (2700 * 3600)*1000)380.01 (0.036 kgCO2e per hour)50%
Portable Receiver5236001,66E+011,28E-034.8electricity grid EF25%
Hi-Fi10272003,62E+011,40E-0338electricity grid EF12.5%
Alarm Clock Radio & Docking Station5236001,66E+011,28E-034.8electricity grid EF12.5%
Synthetic Radio Device8.1251.37536002.88E+010.0025143756.55 (excl. car audio)

Summary

DevicePower Draw (W)PEPS (gCO2e/s)
Personal computer53.20.007
Tablet30.0029
Smartphone0.770.0058
TV System87.40.0096
Smart Speaker2.50.0061
Radio6.55 (excl. in-car)0.0025

Notes and Caveats

  • All of our data is US-centric and probably does not represent typical devices or configurations in less-wealthy countries.

References

Belkhir and Elmeligi, 2018

Lotfi Belkhir, Ahmed Elmeligi, Assessing ICT global emissions footprint: Trends to 2040 & recommendations, Journal of Cleaner Production, Volume 177, 2018, Pages 448-463, ISSN 0959-6526.

Macworld

iPhone Battery Capacities Compared

GSM Arena

GSM Arena battery calculator

Urban et al, 2019

Urban, Bryan & Roth, Kurt & Singh, Mahendra & Howes, Duncan. (2019). Residential Consumer Electronics Energy Consumption in the United States in 2017. 10.2760/667696.

Hischier and Baudin, 2010

Hischier, Roland & Baudin, Isabelle. (2010). LCA study of a plasma television device. The International Journal of Life Cycle Assessment. 15. 428-438. 10.1007/s11367-010-0169-2.

Kwiecień et al, 2019

Kwiecień, Klaudia & Kania, Gabriela & Malinowski, Mateusz. (2019). The life cycle assessment (LCA) of selected TV models.

Malmodin and Lundén, 2018

Malmodin J, Lundén D. The Energy and Carbon Footprint of the Global ICT and E&M Sectors 2010–2015. Sustainability. 2018; 10(9):3027.

Negaoctet

Description of Negaoctet Negaoctet ADEME database 1.4

NRDC, 2019

Horowitz, Hardy, and Tien. The Energy Impacts of Smart Speakers and Video Streaming Devices, August 2019

Amazon, 2023

Amazon Echo Show 5 3rd Gen Product Sustainability Fact Sheet

ADEME ARCEP, 2024

Study of the Environmental Impact of Audiovisual Usage in France - ADEME ARCEP, (FR)