The Airport Carbon Accreditation (ACA) programme
[25]
was launched in 2009 by the Airports Council International Europe and, as of November 2021, includes 362 airports on a global basis. The ACA is a voluntary industry led initiative, overseen by an independent Administrator and Advisory Board, that provides a common framework for carbon management with the primary objective to encourage and enable airports to reduce their CO
2 emissions. All data submitted by airports is externally and independently verified. As of the latest mid 2019 to mid 2021 reporting period, there were 155 European airports participating in the programme corresponding to 65.2% of European passenger traffic (
).
The ACA programme was initially structured around four levels of certification (Level 1: Mapping, Level 2: Reduction, Level 3: Optimisation; Level 3+: Neutrality) with increasing scope and obligations for carbon emissions management (Scope 1: direct airport emissions, Scope 2: indirect emissions under airport control from consumption of purchased electricity, heat or steam and Scope 3: emissions by others operating at the airport such as aircraft, surface access, staff travel).
In 2020, Levels 4 (Transformation48) and 4+ (Transition49) have been added as interim steps towards the long-term goal of achieving net zero CO2 emissions and to align it with the objectives of the Paris Agreement. Guidelines were also published to inform airports about offsetting options, requirements and recommendations, as well as dedicated guidance on the procurement of offsets
[26]
. When applying for Levels 4 and 4+ airports are required to develop both a Carbon Management Plan and a Stakeholder Partnership Plan in order to formulate a long-term absolute reduction trajectory and target for all Scope 1 & 2 emissions, and possibly also Scope 3 emissions. A carbon footprint for the airport’s emissions shall include additional emissions sources compared to the requirements of Levels 3 and 3+ (e.g. deicing substances, refrigerant losses, third non-road emissions, aircraft full flight emissions and offsite emissions such as waste incineration).
As of November 2021, 7 European airports have already achieved accreditation at the highest Level 4+ (Milan Linate Airport, Cannes-Mandelieu Airport, Nice Côte d’Azur Airport, La Môle-Saint-Tropez Airport, Rome-Fiumicino International Airport, Rome-Ciampino International Airport and Rotterdam The Hague Airport).
Due to the impact of COVID-19, the ACA programme decided to merge Years 11 and 12 and treat them as a single reporting year covering mid 2019 to mid 2021. Consequently, each airport submitted one 12 month carbon footprint at different moments during this two year period. Total direct CO2 emissions which were under the full control of accredited European airports (Scope 1 and 2) were reported as 1.845 million tonnes of CO2. The carbon emission per passenger travelling through European airports at all levels of Airport Carbon Accreditation was 1.14 kg CO2/passenger (
).
A total reduction in Scope 1 and 2 emissions compared to a three year rolling average50 of 0.154 million tonnes of CO2 for all accredited airports in Europe was also reported (
). This represents about 7.9% reduction compared to the three-year rolling average. The Scope 3 emissions showed a smaller increase of 0.679 million tonnes of CO
2 compared to an increase by 1.159 million tonnes of CO
2 in 2017-2018 reporting period.
48Definition of a long-term carbon management strategy oriented towards absolute emissions reductions and aligned with the objectives of the Paris Agreement. Demonstration of actively driving third parties towards delivering emissions reductions.
49All Levels 1 to 4 plus offsetting of the residual carbon emissions over which the airport has control.
50Emissions reductions have to be demonstrated against the average historical emissions of the three years before year 0. As year 0 changes every year upon an airport’s renewal/upgrade, the three years selected for the average calculation do so as well. Consequently, airports have to show emissions reductions against a three-year rolling average.