A global carbon offsetting scheme for aircraft operators is set to start in 2021 and run alongside ongoing improvements in engine technology and efficiency. But what about the airports? In light of the energy needs required to power its buildings, infrastructure, ground transport, aircraft movement and more, airports themselves are a major source of carbon emissions. Fortunately, the airport industry is rising to the challenge of addressing a low-carbon future through innovative initiatives such as the Airport Carbon Accreditation programme.

The first key step is to set a vision and put in place a plan to deliver it. The Airport Carbon Accreditation Programme is providing a robust and consistent framework to help more than 200 airports to manage their carbon emissions. For the past 10 years, WSP has been working with Airports Council International to develop and administer its programme. The programme also works in partnership with the United Nations Framework Convention on Climate Change’s Carbon Neutral Now programme and has set a target to have 100 carbon-neutral airports by 2030.

Energy efficiency is an obvious part of the solution and many airports are pushing hard on LED lighting replacements, introducing better metering, monitoring and targeting systems, improving the control of lighting, more efficient boilers, chillers and HVAC systems and introducing power factor correction. However, there is still plenty of potential to be realised. A recent study conducted by WSP for a UK airport operator identified significant carbon savings that would also help to reduce utility costs by up to £2 million annually.

Despite efforts to maximize energy efficiency, airports will always be energy-intensive consumers. It is therefore critical for airports to move toward energy that has a low, and ultimately zero, carbon content. The rapid growth and the shrinking cost of renewable energy generation is enabling more and more organisations to switch to certified zero carbon electricity. For example, Heathrow Airport has adopted zero carbon electricity supply as part of its long-term strategy to operate zero carbon airport infrastructure by 2050.

Airports are also looking at the potential to generate their own renewable energy. Gatwick Airport is innovating in this area, having become the first airport in the world to dispose of Category 1 food waste from aircraft on-site. The treated material is then used to feed biomass boilers, providing a source of renewable energy to heat the airport’s waste management plant and power its water recovery system. The objective is to boost its recycling rate from 49% in 2017 to 85% by 2020 - higher than any UK airport. In India, Cochin International Airport is the world’s first solar-powered airport, producing 60,000 units of electricity every day, which is more than enough to meet its daily requirement.

However successful airports are in lessening the impact of their buildings, infrastructure and vehicles, the fact remains that aviation’s carbon footprint is dominated by the emissions associated with jet fuel. Seattle-Tacoma International Airport, for example, is seeking to become one of the first airports in the world to offer a reliable supply of biofuels which would cut aircraft emissions by up to 25%. WSP has been advising on the infrastructure needed for the storage and blending of aviation biofuels and its integration into the Sea-Tac fuel farm and hydrant system.

To date, the carbon reduction programmes implemented by airports have focussed almost exclusively on operational emissions. However, it is increasingly recognised that the carbon embodied in the construction of buildings and infrastructure, is a very significant part of the whole-life carbon impact of an airport. Estimates vary but some researchers believe embodied carbon could account for up to 50% of the total whole-life impact and it seems clear that this will need much greater attention in the future.

The final challenge is the sheer scale and complexity of the operations at many of today’s airports. Airport operators typically have direct control over a mere 10% of an airport’s total carbon emissions, with the multitude of airlines, caterers, cargo handlers, retailers and so on, responsible for the large majority. Consequently, effective engagement and partnership will be critical to deliver the low-carbon airports of the future.

Airports have come a long way in the last 10 to 15 years in reducing their carbon impact. However, they acknowledge that there is still much to do if they seek to play their full role in the transition to a low-carbon economy.