What is Sustainable Aviation Fuel?

What is Sustainable Aviation Fuel?

The aviation industry contributes approximately 2% of climate change emissions. It’s a sector that’s hard to decarbonize and the market continues to grow. According to a recent scientific study titled Pathways to net-zero emissions from aviation, improvements in aircraft energy efficiency could collectively mitigate up to 27% of carbon dioxide (CO2)—equivalent to 1.2 billion tons—of projected business-as-usual aviation emissions by 2050. But what if aviation embarks on a path to deep decarbonization ahead of other businesses? The driving force behind this transformation is Sustainable Aviation Fuel (SAF), an innovative fuel produced from renewable and waste resources, targeted at reducing greenhouse gas emissions and improving aircraft performance while promising a cleaner future for the planet.

How sustainable aviation fuel works

In 2022, U.S. airlines experienced a significant surge in passenger numbers, with 194 million more passengers compared to the previous year, representing a 30% year over year increase. Throughout the entire year, U.S. airlines transported a total of 853 million passengers, a notable rise from 658 million in 2021 and 388 million in 2020. 

Corporations are increasingly more responsible for their emissions; offsetting them will be a key driver in scaling SAF along with other carbon solutions that go beyond merely compensating for emissions. SAF tackles the issue at its core: it is a replacement jet fuel, thereby directly reducing the aviation sector's carbon footprint. At AIR COMPANY, we're proud to be leading this transformative shift with our pioneering AIRMADE™ SAF technology. It converts excess CO2 into a cleaner-burning aviation fuel, with the same chemical composition as traditional jet fuel.

This isn't just about reducing carbon emissions; it's a revolutionary approach to long-term effective management of waste.

AIR COMPANY's AIRMADE System is a scalable, modular technology solution that transforms our most problematic greenhouse gas—CO2—into an endless resource. This technology converts it into fuels and carbon-negative* chemicals, effectively decarbonizing some of the world's largest industries. 

The AIRMADE™ System employs a five-step process: it starts by sourcing CO2 captured directly from industrial plants before being released into the atmosphere and combining it with green hydrogen (H2) generated through on-site electrolysis. We are also investigating ways to use direct air capture CO2 as part of our future demonstration plants. The captured CO2 and H2 are fed into our patented Carbon Conversion Reactor system, where they meet our catalyst. This facilitates a chemical reaction that produces a reactor liquid composed of alcohols, alkanes and water. This mixture then undergoes a separation process to reach the desired outputs. 

*Carbon-negative solutions remove more carbon dioxide from the atmosphere than is emitted, resulting in a net reduction of atmospheric CO2

What is our sustainable aviation fuel made of? A step-by-step breakdown of the process

Now that we know what sustainable aviation fuel is, you may be wondering what makes AIR COMPANY unique among other SAF companies. Below, we go into more detail about what our SAF is made of by outlining our production process step-by-step:

  • CO2 Capture: The first step involves capturing CO2 from industrial plants before it's emitted into the atmosphere. The CO2 is then cooled, pressurized and liquified, arriving in tanks ready for the next stage. As we continue to scale, we prefer to work with biogenic CO2 for life cycle emission reasons.

  • Electrolysis: On-site electrolysis powered by renewable energy splits water into hydrogen and oxygen. The oxygen is vented as clean air, while the hydrogen is prepared for the Carbon Conversion Reactor.

  • Carbon Conversion: The core of the AIRMADE™ System is the patented Carbon Conversion Reactor. Here, the captured CO2 and H2 meet in a tubular, fixed-bed flow system filled with a proprietary catalyst. This facilitates a chemical reaction that produces a reactor liquid composed of hydrocarbons and water.

  • Distillation: A specialized distillation process is employed to separate the components of the reactor liquid based on their different boiling points, resulting in impurity-free alcohols and alkanes.

  • Outputs: The final products are either distributed to partners or used in AIR COMPANY's range of AIRMADE™ Products.

Once reactor liquid is gathered, it is divided into aqueous and oil components, setting the stage for subsequent processing. This oil layer, comprising paraffins and aromatics, is the compositional formulation of SAF.

The post-processing stage is integral in refining these elements, aligning them with the rigorous requirements of engine and aircraft Original Equipment Manufacturers (OEMs) and the American Society for Testing and Materials (ASTM) D7566 specification.

The post-processing encompasses four essential phases:

  1. Hydrogenation: This step converts the raw fuel mixture into saturated hydrocarbons by removing impurities, essential for creating a 100% drop-in SAF.

  2. Isomerization: Here, paraffins transform from straight-chain to branched hydrocarbons, enhancing the freezing point, which is crucial for high-altitude performance.

  3. Hydrogenation Pt. II: In this step, carbon-carbon double bonds in aromatics turn into cycloparaffins, improving SAF's density and freezing point.

  4. Distillation and Blending: The most critical step, distillation, sorts SAF components by boiling point to achieve the desired carbon distribution. After, components are blended to meet specific standards.

By scaling this technology across all applicable industries, AIR COMPANY aims to make a significant impact, potentially avoiding 10.8% of global CO2 emissions, equivalent to more than 4.6 billion tons of CO2 annually.

So it's eSAF?

Unlike other sustainable aviation fuels, most of which rely on biological feedstocks, eSAF is a groundbreaking synthetic fuel that uses renewable energy to produce hydrogen and then combines such hydrogen and captured carbon dioxide (biogenic or non-biogenic) to produce a clean, low-carbon alternative to fossil-based jet fuels. 

Short for "electro-fuelled sustainable aviation fuel," eSAF is manufactured through a closed-loop system that essentially recycles carbon emissions, offering a higher reduction in lifecycle greenhouse gas emissions in comparison to its fossil jet fuel counterpart. Every molecule of carbon dioxide emitted during combustion is meticulously equalized by the same amount captured during production. The electricity powering this virtuous cycle is sourced exclusively from renewable energies like solar, wind and hydro, creating a blend of ingenuity and responsibility, setting the stage for the future of sustainable aviation.

eSAF can reduce greenhouse gas emissions by up to 100% compared to conventional jet fuel.

Why should we switch to sustainable aviation fuel?

Technological Innovation

The transition to SAF requires groundbreaking technological solutions that can capture and convert greenhouse gases into usable fuel. AIR COMPANY's AIRMADE™ System exemplifies this innovation, utilizing CO2 directly from industrial plants and converting it into cleaner-burning aviation fuel through a patented Carbon Conversion Reactor system once combined with our proprietary catalyst.

Environmental Stewardship

Adopting SAF offers a holistic approach to environmental conservation beyond just reducing carbon emissions. AIR COMPANY's technologies elevate this stewardship by utilizing a closed-loop system that recycles carbon emissions.

Producing SAF from wet wastes, like manure and sewage sludge, reduces pollution pressure on watersheds.

Performance Breakthroughs

The cleaner combustion properties help reduce harmful emissions, enhancing local air quality around airports and contributing to a healthier planet. Our AIRMADE™ SAF has more favorable fuel properties that indicate a higher density fuel in comparison to conventional jet fuel. The technology also has the potential to improve aircraft performance, making air travel not just feasible but more sustainable in the long term.

More benefits of sustainable aviation fuels (and a few challenges)

SAFs contain fewer aromatic components compared to conventional jet fuels. This reduction leads to less particulate matter being emitted from the engines, which in turn reduces the formation of contrails (condensation trails). These are the white lines you see in the sky behind high-flying jets and are known to contribute to climate change by trapping outgoing longwave radiation. According to several studies, contrails are responsible for around 35% of all of the planetary warming from aviation. NASA and the German Aerospace Center (DLR) conclude that sustainable, cleaner-burning jet fuels can reduce ice crystal contrail formation at cruising altitude by 50%-70%, lessening a flight’s environmental impact.

Not all is clear skies, though. Some of the primary challenges for a full SAF rollout include the funding for research and development, limited networks that impede the development of climate-ready logistics and operations, as well as sustainable feedstock sources (such as waste oils and agricultural residues), which can constrain the industry’s expansion. The current technologies for SAF production are often more expensive than conventional jet fuel production methods, making SAF less economically competitive without subsidies or incentives.

Transitioning to 100% SAF would revolutionize the aviation industry, even though it’s likely unfeasible in the current state of the industry. AIR COMPANY's cutting-edge technology leverages abundant and readily available feedstocks to produce SAF, mitigating the challenges of cost and scalability while positioning us at the forefront of a cleaner, more sustainable future for air travel.

Making a lasting impact

Beyond the numbers and the technology lies an ethical dimension. The International Civil Aviation Organization has adopted a long-term global aspirational goal for international aviation of net-zero carbon emissions by 2050 in support of the UNFCCC Paris Agreement's temperature goal. SAFs, with their potential to dramatically reduce lifecycle carbon emissions, are not just an option; they are a critical variable in the aviation industry's carbon equation. 

Embarking on the journey towards fully embracing sustainable aviation fuels is a challenging path strewn with obstacles, including the scaling of technology, infrastructural inadequacies, elevated production expenses, policy formulation, customer readiness to bear additional costs, financial limitations and the complexities of securing capital. 

When we better understand what SAF is and the impact it can have on the aviation industry and environment, we can more effectively implement this technology, influence policy, and carve out a path toward long-term change.

AIR COMPANY stands as a vanguard in this space, pioneering a SAF technology that leverages CO2—an abundant and untapped prime material. This innovative approach not only circumvents traditional barriers but also recycles carbon emissions, offering a promising pathway to one day make 100% AIRMADE™ SAF adoption a tangible reality.

In the broader context of environmental sustainability, AIR COMPANY is a participant leader among SAF companies, reshaping the narrative around sustainable aviation. By converting excess CO2 into eSAF, we’re igniting a shift in our understanding of waste, resources and sustainability.

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