World Average Electricity Carbon Footprint & Environmental Impact

Carbon Footprint:

• The Carbon Footprint of all energy sources except for Solar is based on NREL (2021), which uses cradle to grave emissions factors. The share of energy sources is based on the International Energy Agency (IEA, 2022) with 2019 data. See the table below for individual source emission values and weights.
  • The value for “Supercritical Pulverized Coal” in NREL (2021) is assumed for “Coal” in the IEA Database.
  • The average value for “Natural Gas” of all technologies from NREL (2021) is assumed for “Natural Gas” in the IEA Database.
  • The value for “Oil” in NREL (2021) is used for “Oil” in the IEA Database.
  • The value for “Light Water Reactors” in NREL (2021) is used for “Nuclear” in the IEA Database.
  • The average value for “Wind” for all technologies in NREL (2021) is used for “Wind” in the IEA Database.
  • The average value for “Hydropower” for all technologies in NREL (2021) is used for “Hydro” in the IEA Database.
  • The average value for “Biopower” in NREL (2021) is assumed for “Biofuels” in the IEA Database.
  • The average value for “Geothermal” for all technologies in NREL (2021) is used for “Geothermal” in the IEA Database.
  • The average value for “Concentrating Solar Power” in NREL (2021) is used for “Solar Thermal” in the IEA Database. Value is not adjusted for average solar radiation of each country because a reference solar radiation value is not given.
  • The value for “Waste” in the IEA Database is based on Pfadt-Trilling et al. (2021), who performed a lifecycle of waste, including diverted waste streams from energy recovery, or Waste-to-Energy. The study found a net emission of 0.0824 kg CO2e / kWh, or 82.4 kg CO2e / MWh, which is used for the emission factor or waste energy. Value does not include methane recovery.
  • The value for “Ocean” in NREL (2021) is used for “Tide” in the IEA Database.
  • The weighted average value for all energy sources is used for “Other Sources” in the IEA Database. These sources primarily include energy recovery and purchases of waste heat from other industrial processes. “Other Sources” only made up 0.18% of world energy generation in 2019.
  • See the “Further Resources” Section below for individual assumptions made for each additional fuel source.
   
• The carbon footprint of solar PV is based on the harmonized value of 25 g CO₂e / kWh for monocrystalline solar PV reported by Louwen et al. (2016). Original value is based on Wetzel & Borchers (2015).
  • Solar radiation value of 1,718 kWh m² / yr is based on the Global Solar Atlas (2022) Global Horizontal Irradiation average for all of all land below 60 degrees latitude. Average raster file value was obtained using QGIS (2022). Note this value is likely an underestimation of installed solar capacity, as solar is more likely to be installed in areas with higher solar radiation.
  • Value adjusted to 24.7 g CO₂e / kWh to adjust for 1,700 kWh / m² / yr solar radiation reference value used in Wetzel & Borchers (2015).
  • For further details see the Solar Panels Carbon Footprint & Environmental Impact Page.
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 Land Use:

• The Square Footprint of all energy sources except for Solar is based on Trainor et al. (2016). The share of energy sources is based on the International Energy Agency (2022) with 2020 data. See the table below for individual source emission values and weights.
  • Land use for nonrenewable resources is based on 100 years of resource extraction. Land use of renewable resources stays constant, and the disturbed land only happens once in the lifecycle of energy production. Thus, as additional renewable energy capacity is added, land use change occurs, but only during installation, and not replacement.
  • The values for “Underground Coal” and “Surface Coal” from Trainor et al. (2016) are assumed for “Coal” in the IEA Database. Mining type percentage based on Global Energy Monitor (2022) who states that 51.07% of global coal mines use Surface Coal.
  • The values for “Conventional Natural Gas,” “Shale Gas,” and “Tight Gas” from Trainor et al. (2016) are assumed for “Natural Gas” in the IEA Database. Based on EIA (2016), world Shale Gas production was 42 billion cubic feet per day (bcf/d), out of a total of 342 bcd/f, which totals 12.3%. Exact numbers are not available for the other fuel sources, and therefore a value of 10% is assumed for Coalbed Methane and Tight Gas combined. Therefore, Conventional Natural Gas is assumed to contribute 77.7% of world natural gas production in 2015.
  • The value for “Conventional Oil” of 0.56 km² / TWh / yr (0.56 m² / MWh/ yr) in Trainor et al. (2016) is assumed for “Oil” in the IEA Database.
  • The value for “Nuclear” in Trainor et al. (2016) is assumed for “Nuclear” in the IEA Database. 2020 value is based on 2019 generation.
  • The value for “Wind” in Trainor et al. (2016) is assumed for “Wind” in the IEA Database.
  • The value for “Hydropower” in Trainor et al. (2016) is assumed for “Hydro” in the IEA Database.
  • The value for “Biomass” in Trainor et al. (2016) is assumed for “Biofuels” in the IEA Database.
  • The value for “Geothermal” Trainor et al. (2016) is assumed for “Geothermal” in the IEA Database.
  • The value for “Waste” in the IEA Database is assumed to be 0, as waste energy recovery does not contribute to land use change, and the benefits are considered to be ancillary to the primary land use for waste storage.
  • The value for “Tide” in the IEA Database is assumed to be 0, as it does not affect land use above sea level.
  • The weighted average value for all energy sources is used for “Other Unknown Fuels” in the IEA Database.
  • See the Further Resources Section below for individual assumptions made for each additional fuel source.
   
• The Square Footprint of “Solar PV” and “Solar Thermal” is based on Van de Ven et al. (2021). Average solar generation latitude of 30 degrees is based on Stack Exchange (2021), which states that the average latitude of a sphere is 30 degrees latitude, as well as from Popular Science (2013), which states that most people in the world live at 27 degrees of latitude, which is where power generation is most likely to occur. The average latitude is rounded to 30 degrees as a simplification. See the Solar Land Use Page for further details.
  • Solar radiation value of 1,718 kWh m² / yr is based on the Global Solar Atlas (2022) Global Horizontal Irradiation average for all of world land below 60 degrees latitude. Average raster file value was obtained using QGIS (2022). Note this value is likely overestimates the emission factor of installed solar capacity, as solar is more likely to be installed in areas with higher solar radiation.
  • Assume that 12.3% of installed solar capacity is for rooftop solar PV, based on the average of the middle scenarios presented in Jan Van de Ven (2021). Rooftop solar is considered to have a land use of 0.
   
• Square Footprint of a Parking Space is 144 ft², based on the average dimensions stated by Franklin Street (2019).

• The data presented does not factor energy imports or exports from other countries.
• Average 2020 US Household annual electricity of 10,715 kWh is based on EIA (2021A).
• Carbon Footprint of gasoline is 8.50 kg CO₂e / gallon, based on EIA (2021B).

• Coal Power Carbon Footprint & Environmental Impact
• Geothermal Power Carbon Footprint & Environmental Impact
• Hydropower Carbon Footprint & Environmental Impact
• Natural Gas Power Carbon Footprint & Environmental Impact
• Nuclear Power Carbon Footprint & Environmental Impact
• Solar Land Use
• Solar Panels Carbon Footprint & Environmental Impact
• Wind Power Carbon Footprint & Environmental Impact