This achievement surpassed the original target of reducing carbon intensity by 25%, set in 2010.
Operator Airport Authority Hong Kong and its business partners have also announced a new 10% reduction target as compared with 2015 level for the five-year period from 2016 to 2020.
A pledging ceremony was held at HKIA, officiated by professor Anthony Cheung Bing-leung, Hong Kong's Secretary for Transport and Housing; Wong Kam-sing, Secretary for the Environment; and Fred Lam, CEO of the AAHK.
Lam said: “Today, we are pleased to announce that the airport authority and the airport community have pledged to reduce carbon intensity at HKIA by 10% from the 2015 baseline by 2020.
"We will encourage and provide full support to our business partners in pushing forward low-carbon operations via exchanging experience with their management, establishing technical working groups, organising award schemes, and more.
"Today’s pledge has demonstrated once again that the entire airport community is determined to protect the environment, while operating and developing a world-class airport at the same time.”
Professor Cheung notes: “I would like to express my appreciation to the AAHK and all its business partners for their dedication and joint efforts in working towards a green airport over the past five years.
"I hope the airport authority will continue to enlist support from more business partners and further reduce greenhouse gas emissions."
He adds: "I would like to call upon all players in the aviation industry to share their experience in carbon reduction, and continue to work hand-in-hand with the AAHK to support and realise the new carbon reduction goal, so that HKIA will maintain its pioneering position as the world’s most environmental-friendly and greenest airport.”
Hong Kong's Secretary for the Environment, Wong, says: “It is everyone’s responsibility for tackling climate change.
"I am pleased to see that the airport has received multiple awards and recognitions for its achievements in environmental protection and sustainable development, and its successful completion of the carbon reduction pledge from 2010 to 2015.
"I sincerely hope that the airport would facilitate more aggressive low-carbon initiatives and enlist support from more business partners.
"I look forward that the airport community can reach or even surpass the new goal and create a low-carbon and sustainable society together."
Since 2010, the airport community has completed more than 400 carbon reduction initiatives to achieve its carbon intensity reduction goal.
These include installing over 100,000 LED lights at HKIA and improving cooling systems, as well as introducing electric vehicles and charging facilities.
An online carbon audit system has also been developed for the AAHK and its participating business partners to monitor and report on progress.
In 2013, HKIA received the Airport Carbon Accreditation 'Optimisation/ certificate from ACI in recognition of its carbon emissions management and reduction efforts.
Currently, the number of participating business partners has increased to more than 50. To achieve the new goal, the airport and the airport community will implement more measures to enhance energy efficiency, including optimising the energy consumption of the air-conditioning systems and enhancements to the cooling and lighting systems.
Some of the key initiatives for HKIA include the replacement of over 80,000 LED lights at Terminal 1 to further enhance energy efficiency, optimising the energy consumption of Midfield Concourse, and the conversion of apron high-mast lighting to LED light sources.
The airport has also pledged to collaborate with local and foreign universities to develop smart and quick charging solutions for electric vehicles, and seek to achieve the best energy efficiency with cloud-based analytic energy management system.
Meanwhile, business partners of the airport community will optimise energy consumption of the air conditioning system and install energy-efficient lighting to work towards the reduction goal.