Carbon Management

Carbon Management

The airport community pledges to reduce airport-wide carbon intensity by 10% from 2015 levels by 2020.

The aviation industry is responsible for around 2% of global human greenhouse gas (GHG) emissions1, and of the total aviation emissions, airport operations only account for 2-3%2. Hong Kong International Airport (HKIA) is committed to addressing the impact of climate change. We have developed an airport-wide carbon reduction strategy to drive energy efficiency and further reduce greenhouse gas emissions.

Note 1: Source: “Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report: Climate Change 2007”

Note 2: Source: “Airport Carbon Accreditation Annual Report 2017-2018” ACI-Europe and WSP

Our Story

The “4Ps” approach to reduce airport-wide carbon

Since 2008, the HKIA Carbon Reduction Programme has provided a platform for us to work with business partners to measure, reduce and report carbon emissions.

The success and achievements of the HKIA Carbon Reduction Programme are attributable to the “4Ps”: pledge, platform, partnership and performance.

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In 2008, the Airport Authority (AA) and 40 business partners pledged to reduce airport-wide carbon intensity by 25% by 2015 from a 2008 baseline.

In 2016, the AA and 53 business partners made a second airport-wide carbon reduction pledge to further reduce carbon intensity by 10% by 2020, compared with 2015 levels. The pledge, supported by the Hong Kong Government, the AA’s senior management, business partners and environmental non-governmental organisations, demonstrated the entire airport community’s commitment to further reducing HKIA’s carbon footprint.


The AA developed the Carbon Audit System (CAS) as an online reporting platform to calculate and monitor HKIA’s airport-wide carbon emissions. The business partners participating in the programme can use the system at no cost, enabling them to calculate and analyse their carbon performance on a single, unified platform.


The AA plays an important role in supporting business partners through:

  • Hosting Senior Executive Roundtables to discuss high-level environmental issues;
  • Creating a benchmarking scheme to provide more transparent data about reduction performance;
  • Establishing Technical Working Groups to share the latest developments in carbon and energy saving technologies;
  • Introducing a Carbon Reduction Award Scheme to raise the profiles of top performers and companies adopting best practices.


Despite a strong increase in passenger and cargo throughput between 2008 and 2015, HKIA has significantly accelerated the rate of carbon reduction at HKIA. In 2015, HKIA achieved a 25.6% reduction in carbon intensity compared to the 2008 baseline.

The AA’s continuous engagement has seen the number of business partners joining the HKIA Carbon Reduction Programme growing to 54 in 2017, enhancing awareness of carbon management throughout the airport community. At the end of 2017, a reduction of 5.7% in carbon intensity has been achieved. This is more than halfway towards the airport-wide target to reduce carbon intensity by 10% by 2020 on 2015 levels.


Green buildings and sustainable design

HKIA's terminals are designed to be thermally efficient. They use modern glass façades and building envelopes to reflect heat and reduce cooling loads. North-facing roof skylights optimise natural light during daytime, while minimising heat gain from direct sunlight entering the buildings. Light sensors automatically reduce indoor lighting when there is sufficient daylight. Innovative cooling systems in Terminals 1 cool only the bottom three metres of our large indoor spaces, leaving the air above at ambient temperatures.

The T1 Midfield Concourse is designed to be highly environmentally friendly, and achieved BEAM Plus News Buildings Gold rating. The building has adopted 35 green initiatives covering aspects from material, energy and water use to high-efficiency construction methods.

Massive LED replacement programme

Operating round-the-clock every day, HKIA is a transportation hub that never sleeps. Simply lighting the facilities requires over 130,000 special lighting of different types – accounting for around 10% of the total energy consumption at the airport. In 2009, the AA spearheaded a project to upgrade 100,000 conventional lighting units with more environmentally-friendly Light-Emitting Diodes (LEDs), which was the largest project of its kind in Hong Kong.

LEDs consume less energy than conventional lighting, helping to reduce environmental impact and energy costs. The project, completed in 2015, has saved around 18.2 million kWh of electricity annually and reduced CO2 emissions by 11,500 tonnes.

As these LEDs reach the end of their service life, the AA will replace them with more efficient models by 2020.

ISO 50001 Energy Management System

In November 2016, the AA established its Energy Policy according to the ISO 50001 international standard. The policy acts as a cornerstone for the AA's energy management and demonstrates our commitment to improving our energy performance. Click here to view the Energy Policy.

In February 2017, the AA achieved ISO 50001:2011 Energy Management System (EnMS) Certification for Terminal 1, which specifies the requirements for establishing, implementing, maintaining and improving the energy management system.

The AA will expand the scope to include other terminal areas, office buildings and the apron area, as part of its goal is to operate the world’s most energy efficient international airport.

Airport Carbon Accreditation (ACA)

Airport Carbon Accreditation (ACA) was initially launched by Airports Council International Europe in June 2009 and is the only institutionally endorsed carbon management certification standard for airports. The programme independently assesses the efforts of airports with four progressive levels of accreditation, including "Mapping", "Reduction", "Optimisation" and "Neutrality".

To achieve "Optimisation", or level 3, an airport must show that it has mapped and reduced its carbon emissions and has also engaged stakeholders, including airlines, caterers, ground handlers and others, to reduce their carbon footprints. Our airport-wide Carbon Reduction Programme enabled HKIA to be the first airport in Asia-Pacific to secure ACA level 3 "Optimisation" in 2013, and the first airport in Asia-Pacific to secure a 3-yearly renewal in 2016. In March 2019, HKIA successfully achieved level 3 "Optimisation" again, which is the second 3-yearly renewal under the programme.

Quick Facts


HKIA Carbon Reduction Programme was first implemented in 2008


Airport-wide carbon intensity had been reduced by 25.6% by 2015


10% further reduction in airport-wide carbon intensity by 2020


53 business partners have participated in HKIA’s Carbon Reduction Programme


18m kWh of electricity consumption has been saved by upgrading 100,000 traditional lights to LEDs


The AA accounts for 40% of HKIA’s carbon emissions, while 60% comes from business partners


>400 carbon reduction initiatives have been completed


Absolute GHG emissions (Tonnes of CO2-e)
Intensity-based GHG emissions (kgCO2-e/WLU)
Absolute GHG emissions (Tonnes of CO2-e)
Intensity-based GHG emissions (kg CO2-e/WLU)
  • In 2015, HKIA achieved a 25.6% reduction in carbon intensity compared to the 2008 baseline.
  • Includes AA's facilities such as Terminal 1, T1 Satellite Concourse, SkyPier, HKIA Tower, HKIA Commercial Building, T1 Midfield Concourse, etc. and participating business partners.
  • The methodologies and emission factors applied for the quantification of GHG emissions and removals were in accordance with the Guidelines to Account for and Report on Greenhouse Gas Emissions and Removals for Buildings (Commercial, Residential or Institutional Purposes) in Hong Kong, 2010 Edition issued by EMSD and EPD.
  • The operational boundary covers Scope 1, Scope 2 and selected Scope 3 emission.
  • Workload Unit (WLU): One workload unit is equal to one passenger or 100kg of cargo.
  • The 2008 emission factor as provided by CLP Power Hong Kong Limited, the AA’s electricity provider, was used in the calculation to enable year-on-year comparison of emissions from purchased electricity.


The HKIA Carbon Reduction Programme has earned the AA a number of environmental and sustainability awards, both in Hong Kong and abroad, including

ACI-Airport Carbon Accreditation (ACI-ACA) - level 3 "Optimisation"
Responsible Travel - 2015 World Responsible Tourism Awards - Best Innovation for Carbon Reduction: Silver Award
Hong Kong Green Organisation Certification - Carbon Reduction Certificate
Hong Kong Green Organisation Certification - Energywi$e Certificate (Excellence Level)