Environment in Data

Environmental data including emissions, energy, water and waste

Carbon emissions

Direct (Scope 1) Emissions
2021metric tons CO2e 2020metric tons CO2e 2019metric tons CO2e
Direct (Scope 1) emissions 21,370,485 15,485,363 34,406,941
Mainline aircraft gross emissions 21,253,316 15,392,492 34,263,909
Mainline aircraft – sustainable aviation fuel savings1 (4,790) (4,708) (6,850)
Mainline aircraft net emissions 21,248,526 15,387,784 34,257,059
Mainline vehicles (diesel, gasoline, CNG, LPG) 38,242 24,766 65,161
Facilities (natural gas combustion, engine test cells) 81,997 70,797 80,573
Dry ice from catering 1,720 2,015 4,147
Indirect (Scope 2) emissions
2021metric tons CO2e 2020metric tons CO2e 2019metric tons CO2e
Indirect (Scope 2) emissions 160,794 175,087 189,682
Electricity consumption (location-based) 183,311 196,066 201,690
Electricity consumption (market-based) 160,794 175,087 189,682
Steam consumption 0 0 0
Other Indirect (Scope 3) Emissions
2021metric tons CO2e 2020metric tons CO2e 2019metric tons CO2e
Other Indirect (Scope 3) emissions 5,561,745 4,280,317 7,471,298
Regional aircraft and bus-operated flights (conventional fuel) 5,294,725 4,053,435 7,025,889
Regional vehicles (diesel, gasoline, CNG, LPG) 15,481 13,658 24,588
Ownership stake in Azul Brazilian Airlines 199,099 132,220 244,605
UAV investments2 162 24 12
Employee commuting 52,278 80,980 176,205
Other Indirect (Scope 3) Emissions
2021metric tons CO2e 2020metric tons CO2e 2019metric tons CO2e
Gross GHG emissions 27,093,024 19,940,767 42,067,921
Carbon offsets3 0 (4,106) (15,425)
Net GHG emissions 27,093,024 19,936,661 42,052,496
Other Indirect (Scope 3) Emissions
2021metric tons CO2e 2020metric tons CO2e 2019metric tons CO2e
Revenue ton-miles (RTMs, in millions)4 15,371 9,755 26,655
Metric tons CO2e/million RTMs5 1,401 1,605 1,298
Available seat-miles (ASMs)6 178,684 122,804 284,999
Metric tons CO2e/million ASMs7 150 161 146
Energy consumption
2021 2020 2019
Aircraft — Mainline conventional fuel (millions of gallons) 2,205 1,600 3,562
Aircraft — Mainline sustainable aviation fuel (millions of gallons) 1 1 1
Aircraft — regional conventional fuel (millions of gallons) 523 404 729
Electricity (MWh) 447,714 477,751 489,197
Natural gas (MM BTUs) 1,494,698 1,264,964 1,432,250
Local air quality
2021tons 2020tons 2019tons
NOx emissions 10,813 8,694 17,349
SO2 emissions 1,022 730 1,426
CO emissions 5,503 3,743 8,010
Waste management
2021metric tons 2020metric tons 2019metric tons
Waste — total 31,407 26,667 53,832
Hazardous and non-hazardous waste generation 24,253 15,602 26,621
Catering — Municipal waste 10,367 11,066 27,210
Recycling — total 5,818 4,468 8,332
Non-catering — recycled 4,446 3,302 4,489
Catering — recycled 1,372 1,166 3,843
Water consumption
2021millions of gallons 2020millions of gallons 2019millions of gallons
Billed water consumption8 661 484 521

Footnotes

  1. United accounts emissions reductions associated with the use and combustion of sustainable aviation fuel (SAF) to be a Scope 1 reduction, as it is in-sector and a sustainable alternative to the conventional jet fuel usage that is accounted in the gross emissions of this Scope. This is an interpretation of the GHG Protocol, until such time that an accepted GHG accounting methodology is developed to reflect in-sector reductions associated to biogenic products.
  2. United Airlines Ventures investments in Alder Fuels, Archer Aviation, Boom, Clear, Fulcrum BioEnergy, Heart Aerospace, and ZeroAvia (some of which may not have developed GHG inventories yet)
  3. Offset purchases made in 2019 and 2020 were part of discrete promotional campaigns originally offered in late 2019 through the beginning of 2020. These promotions were offered prior to United’s announcement in December 2020 of its commitment to reduce 100% of its GHG emissions by 2050 without the voluntary use of traditional offsets and are no longer part of United’s promotional campaigns. United may be subject to future regulatory requirements that require the purchase of carbon offsets
  4. The number of revenue, passenger and cargo, tons transported multiplied by the number of miles flown on each segment
  5. Scope 1+2 emissions/Mainline RTMs; metric used for tracking progress against industry goal of 1.5%/year efficiency improvement
  6. The number of seats available for passengers multiplied by the number of scheduled miles those seats are flown
  7. Scope 1+2+3 Regional emissions/Mainline+Regional ASMs; metric used for tracking progress against our 2035 and 2050 climate change goals
  8. Does not account for all United locations or locations shared with other businesses (e.g., terminals) and as a result may change considerably from year to year

Totals may not add up due to rounding.