top of page
worldenvironmentdayPSbig.png

CARBON REMOVAL

Carbon removal is the process by which humans actively and intentionally remove carbon dioxide (CO2) from the atmosphere and store it in longer-lived reservoirs.

worldenvironmentdayPSbig.png

SAF (Sustainable Aviation Fuel)

SAF, which stands for sustainable aviation fuel, is an alternative fuel derived from renewable or sustainable sources that reduces carbon emissions from aviation.

Video caption

SAF, which stands for sustainable aviation fuel, is an alternative fuel derived from renewable or sustainable sources that reduces carbon emissions from aviation. SAF powers aircraft with similar performance as conventional petroleum-made fuel, but can reduce up to 85% of the emissions.

 

99% of SAF today are biofuels made from renewable biomass and waste sources. Bio-made SAF includes resources such as agricultural products, cooking fats/oils, municipal waste streams. However, there are several emerging technologies poised to make up a large share of the SAF market. These include renewable carbon feedstocks produced from the electrochemical conversion of carbon dioxide and other carbon waste.[1]

image.png

Sustainable aviation fuel production cycle. 

[I took this picture from the internet. However, I would love to have a graphic that better represents the technological cycle the carbon undergoes, illustrating why SAF is carbon-neutral.

Benefits of SAF beyond lowering emissions:

  • increased profits for agricultural workers

  • environmental protections

  • fewer pollutants in the atmosphere besides greenhouse gas emissions, such as sulfur oxides

Why do we need SAF?

The transportation sector plays an important role in our energy systems and significantly contributes to greenhouse gas emissions. Transportation accounts for 12% of global emissions; aviation alone contributes to 2% of global emissions. Transportation — aviation in particular — will require innovative solutions to decarbonize and reduce their emissions. Most airlines have committed to net-zero carbon emissions by 2050, and most will rely on SAF to achieve this ambitious goal.

 

 

Most modes of transportation will decarbonize by electrification; however, the aviation sector cannot be fully electrified with current technology. The amount of electricity required to power standard commercial aircraft would have to be stored in extremely large and weighty batteries or hydrogen storage, so large and weighty that a plane could not fly. Furthermore, electric airplanes would require significant retrofitting of aviation infrastructure, introducing additional costs. Thus, decarbonization of air transport will require carbon-neutral "drop-in" fuels: liquid fuels which contain the same chemical composition and functionality as standard jet fuel, but are derived from non-petroleum sources.

Examples of SAF production methods include:
Cooking oils

Vegetable oils and similar products can be refined into biofuels.

1.png
Agricultural waste

Agricultural waste includes any unwanted or unprofitable parts of a crop that are not used for consumption, typically vines, stems, or leaves.

3.png
Algae 

Micro-algae farming yields large amounts of biomass precursor that can be processed into SAF.

5.png
Carbon conversion 

Carbon dioxide is chemically converted into other ethanol and other carbon feedstocks that can be used as SAF.

7.png
Animal waste fat

Animal fat generated as waste by-products of the meat industry, including fat from pigs and cows, are incorporated in biofuels.

2.png
Municipal waste 

Municipal waste includes residential and commercial garbage as well as sewage sludge. 

4.png
Energy crops 

Oil seed cover crops can be grown in rotation during the year with other cereal crops, when that land would otherwise be unused.

6.png
Green hydrogen 

Electricity produced from renewable sources splits water molecules into oxygen and hydrogen. The latter only emits water when burned as a fuel.

8.png
What are the challenges of SAF?

Incorporation of SAF into our energy systems presents several challenges. In order to be used as a "drop-in" fuel that functions in existing airplane infrastructure, SAF must be blended with conventional aviation fuel. Current regulations limiting SAF blending to a maximum 50% component of the fuel. This demands extensive testing and investment to ensure compatibility without compromising safety or performance. Additionally, the high costs associated with SAF production remain a formidable hurdle, hindering widespread adoption. To address this, innovative financing models and government incentives are essential to drive down costs and incentivize investment in SAF production technologies.

 

Moreover, expanding the range of usable waste products to meet SAF demand introduces logistical and environmental considerations. Increasing the sources of feedstock for SAF production must be done carefully to avoid disrupting the food supply chain or triggering detrimental land use changes. The delicate balance between the needs of waste stream sources, food security, and natural ecosystems is paramount. Collaborative efforts between industry stakeholders, policymakers, and environmental advocates are necessary to navigate these challenges and realize the potential of SAF as a viable alternative to traditional jet fuels.

[insert video about SAF here]

Here are some useful resources to learn more about SAF:

Footnotes

[1] References 

[video caption: "Watch here to learn more about SAF... etc.]

bottom of page