Sustainable Aviation Fuels (SAF) 101

WHAT IS SAF?

Sustainable aviation fuels (SAF) represent a broad category of fuels derived from non-fossil sources, including advanced biofuels and e-fuels, offering a sustainable alternative to conventional jet fuel. Generally, SAF exhibits three key features: Firstly, it is considered sustainable, which means it can be sourced repeatedly and continually in a way that aligns with economic, social, and environmental goals. This helps maintain ecological balance by avoiding the depletion of natural resources.

Secondly, it is a fuel designed for aviation that uses alternative, nonconventional or advanced feedstocks for production instead of crude oil. It is also processed to jet fuel in an alternative manner. The feedstocks can take various forms, including plant oils, cooking oils, waste gases, agricultural residues, and municipal waste.

Lastly, SAF is a jet fuel that of course meets the technical and certification requirements for use in commercial aircraft.

WHY DO WE NEED SAF?

The significance of SAF lies in their capability to mitigate the environmental impact of air travel. The aviation industry contributes around 2.5% of global carbon dioxide emissions, and these numbers are set to rise with the increasing demand for air travel. SAF provide an answer to this looming crisis.

The International Air Transport Association (IATA) estimates that SAF could contribute approximately 65% of the emissions reduction necessary for aviation to achieve its goal of reaching net zero CO2 emissions by 2050. SAF could also reduce the lifecycle greenhouse gas emissions by up to 80% when compared to conventional jet fuel.

Besides their environmental benefits, SAF holds practical advantages too. They are 'drop-in' fuels, meaning that they can be blended with conventional jet fuel and used in existing aircraft engines without any need for modification. This attribute can substantially simplify and accelerate the transition from fossil-based fuels to SAF in the aviation industry.

HOW SUSTAINABLE IS SAF?

The use of SAF alone does not necessarily reduce overall carbon emissions. Different production methods can have vastly different impacts.

For instance, a study found that the biofuel made from palm oil produced in Indonesia would have 24 times the impact of SAF produced from grass in the United States due to deforestation associated with palm cultivation.

However, achieving a net reduction in carbon emissions is a crucial reason for using SAF to meet the aviation industry's ambitious climate goals. To ensure that

SAF has a positive impact, it must undergo lifecycle analysis and meet sustainability certification criteria.

Governmental financial incentives for SAF production or use are typically available for SAF that meets sustainability standards. These include the US Renewable Fuels Standard (RFS2), the EU Emissions Trading Scheme (EU ETS), the EU Renewable Energy Directive (RED), and CORSIA. Notably, in the US and EU, only certified SAF can contribute to government mandates for renewable fuel volumes or quotas.

Source: Beginner's Guide to Sustainable Aviation Fuel - ATAG

WHY AREN'T WE SWITCHING TO SAF RIGHT AWAY?

Producing and deploying SAF involves a complex array of challenges that need to be overcome for the widespread adoption of these fuels in the aviation industry. Some of the key challenges include:

High Production Costs

01 02 SAF - STATE OF THE INDUSTRY 2023

Feedstock Availability

The primary challenge for SAF is its high cost of production compared to conventional jet fuels because the production processes of SAF are technically complex and resource-intensive. Plus, the cost of feedstocks and their processing can significantly increase the total cost. The current costs of SAF are 2 to 8 times higher than those of conventional jet fuel. For SAF to become competitive, significant technological improvements and economies of scale are required.

Technological Challenges

While the technology to produce SAF is proven, there are challenges related to efficiency, scalability, and the processing of certain feedstocks. For instance, the technology for producing SAF from algae or municipal waste is still in its nascent stages and needs further development to become commercially viable. For e-fuels, the problem of large-scale production is the same: all the world's renewable electricity would not be sufficient to produce the amount of fuel used by aviation today.

Infrastructure Requirements

SAF are 'drop-in' fuels that can be used in existing aircraft and infrastructure without modifications. However, incorporating SAF into the existing fuel supply chain infrastructure poses logistical challenges. These include segregation and quality control issues during blending, transportation, and storage. Moreover, consider this: the Norsk e-fuel plant could eventually produce 100 million litres of fuel per year, but it would take dozens of similar plants to supply Charles de Gaulle airport in Paris alone.

REGULATORY & POLICY SUPPORT

Regulatory support is vital to stimulate the production and uptake of SAF. Inconsistent policies and regulations across different regions can pose a challenge. Policymakers need to implement a harmonised set of incentives, standards, and mandates to foster the growth of the SAF industry.

The adoption of SAF is not just a technical or economic issue, but also a systemic challenge requiring coordinated efforts from all stakeholders, including fuel producers, airlines, governments, and research institutions. Addressing these challenges is crucial for a sustainable transition towards a low-carbon future for aviation.