Fuel efficiency and emissions reduction

Improvements in fuel efficiency

Carbon footprint management and fuel efficiency improvement are critical to our commitment to operate an environmentally sustainable airline in the air, on the ground and at our facilities.

Here are the actions we take to improve our fuel efficiency.

In the air

Since 1994, we've improved our fuel efficiency by more than 35 percent. In an effort to maintain this commitment, United has made significant investments in a modern, fuel-efficient fleet while implementing operational and procedural changes to drive fuel conservation.

Weight reductions

We constantly review the amenities of our aircraft for lighter-weight alternatives, as lighter aircraft burn less fuel and produce fewer emissions. Learn more

Single-engine taxiing

Shutting down one engine and taxiing on the other saves five million gallons per year, or the equivalent of removing 9,000 cars from the road.

Continuous descent approaches

By avoiding applying thrust in the higher density air at low altitudes, aircraft can save fuel—while also reducing noise impacts to cities such as Los Angeles.

Towing aircraft

Rather than taxiing aircraft between flights, United’s fleet of 69 SuperTugs at 10 airports saves eight million gallons each year by moving nearly 500 aircraft every day between the gates and hangars.

Engine washes

We routinely wash our aircraft engines to reduce drag and emissions.

Auxiliary power unit savings

Where possible, we provide aircraft parked at the gate with air conditioning and electric power via alternative, emissions-reducing methods rather than using the aircraft’s own auxiliary power unit.

On the ground and at our facilities

On the ground

Over 4,000 of our ground service equipment (GSE) around the world is electric or uses alternative fuels. That percentage is even higher at specific locations, including Denver (50 percent), San Francisco (65 percent), Houston Intercontinental (70 percent) and Los Angeles (70 percent). United also encourages employee ridesharing and provides commuter rail benefits and electric vehicle charging at select locations.

At our facilities

United has LEED certified buildings in Chicago, Houston and San Francisco. One of the largest green roofs in Chicago is on our United Cargo building at O’Hare. Also, we’re conducting an energy efficiency audit on our top 10 energy using facilities in our network, which make up 85 percent of our non-fuel energy use.


Chart, aviation’s impact on the environment.  The entire aviation industry produces approximately two percent of human-induced carbon dioxide emissions. Other industries account for 98 percent of human-induced carbon dioxide emissions. Major contributors include: electricity and heat production, 25 percent; agriculture, forestry and other land use, 24 percent; industry, 21 percent; non air transportation, 12 percent; other energy, 10 percent; buildings, 6 percent.

Aviation’s impact on the environment

Aviation stimulates the economy, trade and tourism, generates business opportunities and enhances quality of life in both developed and developing regions. However, aviation does produce approximately two percent of human-induced CO2 emissions.

We support a global approach to addressing greenhouse gas emissions. Together with other airlines, engine and airframe manufacturers, fuel suppliers, airports and governments, we’re working towards a collective industry goal of 1.5 percent average annual fuel efficiency improvement through 2020, carbon neutral growth beginning in 2020 and a 50 percent reduction in airline CO2 emissions by 2050.

United is involved with the Carbon Disclosure Project (CDP), becoming the first U.S. airline to fully participate. For additional information on our carbon footprint and climate change strategy, view our latest CDP questionnaire responses.

You can also view our entire emissions footprint on our Corporate Responsibility Report. Read more

There are three types of emissions we have, explained below this image. The total emissions for Scope 1, labeled in blue, are 31,447,052 metric tons of carbon dioxide equivalent. The total emissions for Scope 2, labeled in yellow, are 291,543 metric tons of carbon dioxide equivalent. The total emissions for Scope 3, labeled in teal, are 6,268,793 metric tons of carbon dioxide equivalent. There are three types of emissions we have, explained below this image. The total emissions for Scope 1, labeled in blue, are 31,447,052 metric tons of carbon dioxide equivalent. The total emissions for Scope 2, labeled in yellow, are 291,543 metric tons of carbon dioxide equivalent. The total emissions for Scope 3, labeled in teal, are 6,268,793 metric tons of carbon dioxide equivalent. There are three types of emissions we have, explained below this image. The total emissions for Scope 1, labeled in blue, are 31,447,052 metric tons of carbon dioxide equivalent. The total emissions for Scope 2, labeled in yellow, are 291,543 metric tons of carbon dioxide equivalent. The total emissions for Scope 3, labeled in teal, are 6,268,793 metric tons of carbon dioxide equivalent.
Blue - Scope 1

Emissions from sources that are owned and/or controlled by United. This includes:

Jet fuel for United flights -31,282,902*

Biofuel - 10,237

Vehicles - 78,196

Facilities - 72,486

Dry ice from catering - 3,231

*in metric tons CO2e

Yellow - Scope 2

Emissions from the consumption of purchased electricity or other energy sources. This includes:

Electricity consumption - 291,543

Green - Scope 3

Emissions from sources not directly owned and/or controlled by United. This includes:

Regional jet fuel - 6,157,267

Ownership stakes in other companies - 109,678

Vehicles - 1,847

United Global Performance Commitment

Our industry-leading program for select corporate travel partners represents our continued commitment to operational performance excellence throughout the entire travel process. In 2017, United added an environmental commitment that we’ll have a lower gross carbon footprint than American and Delta.

Learn more

United Eco-Skies CarbonChoice carbon offset program

Through the Eco-Skies® CarbonChoice program, United offers customers and businesses the opportunity to purchase carbon offsets to reduce the carbon footprint associated with their air travel and cargo shipments.

Learn more

Emissions and other data

Every year, we report on our carbon emissions, local air quality, waste management, water and energy consumption and more. See the table below for our latest data.

Carbon emissions

Carbon emissions - Direct (Scope 1) emissions
 
2016 in metric tons CO2e
2015 in metric tons CO2e
2014 in metric tons CO2e
Direct (Scope 1) emissions31,447,05231,446,16631,132,366
Aircraft (jet fuel)31,282,90231,279,28830,966,621
Aircraft (biofuel)10,23700
Vehicles (diesel, gasoline, CNG, LPG)78,19678,31575,361
Facilities (natural gas combustion, engine test cells)72,48688,56390,384
Dry ice from catering3,231Not reportedNot reported
Intensity ratio (Scope 1+2 metric tons CO2e / 1000 RTMs)11.3631.3911.423

Carbon emissions - Direct (Scope 1) emissions

  • 2016 in metric tons CO2e
    31,282,902
  • 2015 in metric tons CO2e
    31,279,288
  • 2014 in metric tons CO2e
    30,966,621

  • 2016 in metric tons CO2e
    10,237
  • 2015 in metric tons CO2e
    0
  • 2014 in metric tons CO2e
    0

  • 2016 in metric tons CO2e
    78,196
  • 2015 in metric tons CO2e
    78,315
  • 2014 in metric tons CO2e
    75,361

  • 2016 in metric tons CO2e
    72,486
  • 2015 in metric tons CO2e
    88,563
  • 2014 in metric tons CO2e
    90,384

  • 2016 in metric tons CO2e
    3,231
  • 2015 in metric tons CO2e
    Not reported
  • 2014 in metric tons CO2e
    Not reported

  • 2016 in metric tons CO2e
    1.363
  • 2015 in metric tons CO2e
    1.391
  • 2014 in metric tons CO2e
    1.423

Carbon emissions - Indirect (Scope 2) emissions
 
2016 in metric tons CO2e
2015 in metric tons CO2e
2014 in metric tons CO2e
Indirect (Scope 2) emissions291,543283,499416,062
Electricity consumption291,543283,499416,062

Carbon emissions - Indirect (Scope 2) emissions

Indirect (Scope 2) emissions

  • 2016 in metric tons CO2e
    291,543
  • 2015 in metric tons CO2e
    283,499
  • 2014 in metric tons CO2e
    416,062


Electricity consumption

  • 2016 in metric tons CO2e
    291,543
  • 2015 in metric tons CO2e
    283,499
  • 2014 in metric tons CO2e
    416,062

Carbon emissions - Other Indirect (Scope 3) emissions
 
2016 in metric tons CO2e
2015 in metric tons CO2e
2014 in metric tons CO2e
Other Indirect (Scope 3) emissions6,268,7936,474,3147,022,328
Regional jet fuel6,157,2676,472,5047,020,223
Vehicles (diesel, gasoline, CNG, LPG)1,8471,8092,105
Ownership stakes in other companies109,678Not reportedNot applicable

Carbon emissions - Other Indirect (Scope 3) emissions

  • 2016 in metric tons CO2e
    6,268,793
  • 2015 in metric tons CO2e
    6,474,314
  • 2014 in metric tons CO2e
    7,022,328

  • 2016 in metric tons CO2e
    6,157,267
  • 2015 in metric tons CO2e
    6,472,504
  • 2014 in metric tons CO2e
    7,020,223

  • 2016 in metric tons CO2e
    1,847
  • 2015 in metric tons CO2e
    1,809
  • 2014 in metric tons CO2e
    2,105

  • 2016 in metric tons CO2e
    109,678
  • 2015 in metric tons CO2e
    Not reported
  • 2014 in metric tons CO2e
    Not applicable


Local air quality

Local air quality - NOx emissions
 
2016 in tons NOx
2015 in tons NOx
2014 in tons NOx
NOx emissions17,88113,13913,027
Mainline aircraft (jet fuel)16,82311,98811,864
Vehicles (diesel, gasoline, CNG, LPG)9461,0221,032
Facilities (Natural gas combustion, engine test cells)111129131

Local air quality - NOx emissions

  • 2016 in tons NOx
    17,881
  • 2015 in tons NOx
    13,139
  • 2014 in tons NOx
    13,027

  • 2016 in tons NOx
    16,823
  • 2015 in tons NOx
    11,988
  • 2014 in tons NOx
    11,864

  • 2016 in tons NOx
    946
  • 2015 in tons NOx
    1,022
  • 2014 in tons NOx
    1,032

  • 2016 in tons NOx
    111
  • 2015 in tons NOx
    129
  • 2014 in tons NOx
    131

Local air quality - SO2 emissions
 
2016 in tons SO2
2015 in tons SO2
2014 in tons SO2
SO2 emissions1,5981,1731,171
Mainline aircraft (jet fuel)1,5971,1721,170
Facilities (Natural gas combustion, engine test cells)111

Local air quality - SO2 emissions

  • 2016 in tons SO2
    1,598
  • 2015 in tons SO2
    1,173
  • 2014 in tons SO2
    1,171

  • 2016 in tons SO2
    1,597
  • 2015 in tons SO2
    1,172
  • 2014 in tons SO2
    1,170

  • 2016 in tons SO2
    1
  • 2015 in tons SO2
    1
  • 2014 in tons SO2
    1

Local air quality - CO emissions
 
2016 in tons CO
2016 in tons CO
2016 in tons CO
CO emissions11,0349,164
9,231
Mainline aircraft (jet fuel)9,0586,3706,324
Vehicles (diesel, gasoline, CNG, LPG)1,9182,7242,836
Facilities (Natural gas combustion, engine test cells)587071

Local air quality - CO emissions

  • 2016 in tons CO
    11,034
  • 2016 in tons CO
    9,164
  • 2016 in tons CO
    9,231

  • 2016 in tons CO
    9,058
  • 2016 in tons CO
    6,370
  • 2016 in tons CO
    6,324

  • 2016 in tons CO
    1,918
  • 2016 in tons CO
    2,724
  • 2016 in tons CO
    2,836

  • 2016 in tons CO
    58
  • 2016 in tons CO
    70
  • 2016 in tons CO
    71


Waste management

Waste - total
 
2016 in metric tons
2015 in metric tons
2014 in metric tons
Waste — total41,78643,756
49,948
Catering — Municipal waste25,057Reported in another categoryReported in another category
HazardousMoved to new category2,565555
Non-hazardous/other wasteMoved to new category41,191
49,393
Recycling — total5,82414,942
9,329
Non-Catering — recycled4,09312,8406,454
Catering — recycled1,7302,1022,875

Waste - total

  • 2016 in metric tons
    41,786
  • 2015 in metric tons
    43,756
  • 2014 in metric tons
    49,948

  • 2016 in metric tons
    25,057
  • 2015 in metric tons
    Reported in another category
  • 2014 in metric tons
    Reported in another category

  • 2016 in metric tons
    Moved to new category
  • 2015 in metric tons
    2,565
  • 2014 in metric tons
    555

  • 2016 in metric tons
    Moved to new category
  • 2015 in metric tons
    41,191
  • 2014 in metric tons
    49,393

  • 2016 in metric tons
    5,824
  • 2015 in metric tons
    14,942
  • 2014 in metric tons
    9,329

  • 2016 in metric tons
    4,093
  • 2015 in metric tons
    12,840
  • 2014 in metric tons
    6,454

  • 2016 in metric tons
    1,730
  • 2015 in metric tons
    2,102
  • 2014 in metric tons
    2,875


Water consumption

Water consumption
 
2016 in gallons
2015 in gallons
2014 in gallons
Billed water consumption2453,388,311343,393,628
355,318,889

Water consumption

Billed water consumption2

  • 2016 in gallons
    453,388,311
  • 2015 in gallons
    343,393,628
  • 2014 in gallons
    355,318,889


Energy consumption

Energy consumption
 
2016
2015
2014
Electricity (MWh)616,396561,586
763,023
Aircraft (Mainline jet fuel – millions of gallons)3,2613,216
3,183
Natural gas (MM BTUs)1,279,5451,579,0851,204,290

Energy consumption

  • 2016
    616,396
  • 2015
    561,586
  • 2014
    763,023

  • 2016
    3,261
  • 2015
    3,216
  • 2014
    3,183

  • 2016
    1,279,545
  • 2015
    1,579,085
  • 2014
    1,204,290


Other

Other
 
2016
2015
2014
Revenue Ton-Miles (RTMs — millions)123,28222,813
22,176
CO2e/1,000 RTMs11.3631.3911.423

Other

Revenue Ton-Miles (RTMs — millions)1

  • 2016
    23,282
  • 2015
    22,813
  • 2014
    22,176

CO 2 e/1,000 RTMs1

  • 2016
    1.363
  • 2015
    1.391
  • 2014
    1.423

Footnotes

1Scope 1+2/Mainline only; calculation changed in 2016 based on better passenger weight assumptions; new values are approximately 9% higher

2Does not account for all United locations or locations shared with other businesses (e.g., terminals)