The Soaring Cost of Green Skies: Decarbonizing Dublin Airport and the Future of Aviation
The future of flight is facing a stark reality: decarbonization isn’t just about cleaner engines, it’s about massive land use and energy demands. A recent analysis, spearheaded by researchers at University College Cork (UCC), reveals the staggering scale of resources needed to eliminate carbon emissions associated with flights from Dublin Airport. The challenge is particularly acute for Ireland, where per capita air travel is almost double the European average.
Why Aviation is a Climate Challenge
Unlike road transport or power generation, aviation lacks readily available, commercial-scale alternatives to fossil jet fuel. This makes it one of the most difficult sectors to decarbonize. Dublin Airport alone accounts for approximately 85% of Ireland’s total aviation emissions, contributing 6% of the country’s overall emissions in 2024 – equivalent to half of all emissions from power generation.
The Four Pathways to Decarbonization: A Trade-Off Analysis
Researchers at UCC explored four potential approaches, each with its own set of hurdles. These fall into two main categories: replacing fossil fuels with lower-carbon alternatives, and continuing to use jet fuel while actively removing carbon dioxide from the atmosphere.
Replacing Fossil Fuels: Biofuels and Synthetic Fuels
Sustainable aviation fuels (SAF) are currently the only viable low-carbon fuel option for existing aircraft, offering potential emission reductions of up to 80%. However, global supply is severely limited, representing less than 1% of current jet fuel usage. Producing enough bio-SAF in Ireland would require a substantial 0.4 to 1 million hectares of land – 9% to 21% of the country’s agricultural land.
Waste-based fuels offer a solution to the land-use issue, but resources are scarce. Diverting all used cooking oil in Ireland would only cover 0.5% of Dublin Airport’s jet fuel needs. Synthetic fuels, or electro-fuels, created using green hydrogen and captured carbon dioxide, avoid land pressure but are incredibly energy intensive. Replacing all jet kerosene with e-SAF would demand around 42 TWh of electricity – 15% more than Ireland’s total 2024 electricity demand.
Meeting this demand would necessitate significant renewable energy infrastructure, requiring approximately 71,000 hectares of solar farms or 78,000 hectares of wind farms. Alternatively, around 9 GW of offshore wind capacity would be needed, ten times the capacity of one of Ireland’s first planned offshore wind farms.
Carbon Removal: Direct Air Capture and Afforestation
Continuing to use jet fuel while offsetting emissions through carbon removal presents its own challenges. Direct Air Capture (DAC) technology, which separates carbon dioxide from the air, is expensive, energy-intensive, and currently at a very early stage of deployment. Offsetting Dublin Airport’s annual emissions would require 5.7 TWh of electricity annually and land equivalent to Killarney National Park.
Afforestation, or planting trees, is often seen as a natural solution, but the scale required is immense. Offsetting Dublin Airport’s emissions could necessitate between 0.3 to 1.6 million hectares of new forestry – 6% to 34% of Ireland’s agricultural land, an area roughly the size of Co. Tipperary or nearly the entire province of Connacht. Ireland is already falling short of its current afforestation targets, with only 20% of the annual target met in 2023 and 2024.
No Easy Answers: Demand Management and Systemic Change
The analysis underscores that there is no land-free or cheap pathway to decarbonizing aviation. A combination of approaches, alongside demand management, will be crucial. As passenger numbers rise, so too will the scale and cost of the necessary solutions. Decarbonizing aviation will compete with other sectors for land, electricity, infrastructure, and capital.
FAQ: Decarbonizing Aviation in Ireland
Q: What is Sustainable Aviation Fuel (SAF)?
A: SAF is a low-carbon fuel compatible with existing aircraft, offering potential emission reductions of up to 80% compared to conventional jet fuel.
Q: How much land would be needed to produce enough bio-SAF in Ireland?
A: Between 0.4 and 1 million hectares, equivalent to 9% to 21% of Ireland’s agricultural land.
Q: What is Direct Air Capture (DAC)?
A: DAC is a technology that removes carbon dioxide directly from the air, but it is energy-intensive and currently expensive.
Q: Is afforestation a viable solution for offsetting aviation emissions?
A: While afforestation can aid, the scale required is enormous – potentially between 0.3 to 1.6 million hectares of new forestry.
Q: What is the role of demand management in decarbonizing aviation?
A: Reducing the demand for flying is the most direct way to cut emissions, but it is as well politically sensitive.
Did you know? Ireland’s per capita air travel is almost double the European average, making the decarbonization challenge particularly acute.
Pro Tip: Consider alternative travel options, such as rail, for shorter distances to reduce your carbon footprint.
The future of aviation hinges on acknowledging these trade-offs and fostering a transparent conversation about the resources required to achieve meaningful decarbonization. As decisions are made about expanding airport capacity, a clear understanding of these costs is paramount.
Explore more insights on sustainable energy and climate action at UCC’s Energy Policy and Modelling Group.
