#17 Sustainable Aviation Fuel (SAF)

No longer feeling guilty about traveling by plane

Mar 11, 2023

Read time: 4 minutes

In this week’s issue you will learn about a way to massively reduce the emissions from air travel: Sustainable Aviation Fuel (SAF)

“SAF could contribute around 65% of the reduction in emissions needed by aviation to reach net-zero in 2050“ - International Air Transport Association

Top SAF News 🗞️

First flight with CO2 made fuel: Air Company fueled the first-ever test flight using 100% unblended sustainable aviation fuel made directly from CO2, conducted in partnership with the U.S. Air Force.

United Airlines is leading in SAF: Thanks to its environment-focused CEO, the airline is investing in SAF more than double the rest of the world’s airlines combined.

SAF in helicopters: Neste, by far the largest SAF producer, has helped helicopter manufacturer Bell complete its first flight fueled solely by 100% sustainable aviation fuel.

Let’s dive in 🧠

Traveling by plane is awesome but sadly, if you take several flights a year, that’s BY FAR the largest contributor to your carbon footprint.

The aviation industry accounts for 2% to 3% of global CO2 emissions.

AITA (International Air Transport Association) has already drafted a plan to reach net zero by 2050, and at least 65% of getting there is going to happen thanks to SAF.

So what is SAF?

SAF includes many different fuels derived from non-fossil sources or ‘feedstock’.

Nowadays the vast majority of SAF is made out of plants, used cooking oil, food scraps, solid municipal waste, and other types of solid waste.

But, it can't be made from anything that:

Diverts land use from food crops
Consumes too much fresh water
Destroys forests

Because that's not sustainable.

Source: Environmental and Energy Study Institute

Why not just use electric planes or have them use hydrogen as fuel?

Because electric only works for short distance and if you want to use hydrogen you need to change many parts of the plane for it to work properly.

The good thing about SAF is you can use it in today’s planes, it’s “drop-in ready” as they say.

How is it made?

This will depend on the specific waste material used.

But overall you need to collect the waste, purify it a lot, refine it, and turn it into fuel.

All of this requires a lot of energy and transportation. Ideally all powered by renewables.

It’s very difficult to make the whole process carbon neutral, that’s why, even though the raw material is some type of waste, SAF helps achieve around an 80% reduction in overall CO2 emissions.

SAF made from CO2

Now there are several startups coming up with ways to use emitted CO2 as the raw material for making SAF!

The way this works varies by company but the overall idea is this:

Get CO2 from some place emitting high concentrations of CO2 (like a steel factory).
Use renewables to produce green hydrogen from water with an electrolyzer.
Mix the green hydrogen with the captured and distilled CO2.

Currently less than 1% of total fuel available is SAF. Nonetheless, airlines worldwide are investing in it and making partnerships with SAF producers which will boost its use and lower the price rapidly.

Cons

Scale: We currently produce hundreds of millions of litters per year and we need to produce tens of billions. Making SAF is quite a new and complex process so reaching the right scale will take time.

Cost: IATA estimates SAF costs two to four times as much as any aviation fuel. Both Government support and making it available in more locations is needed.

Energy: Producing SAF requires significant energy and it should come from renewables. The issue is we also need that renewable energy for many more things.

Top SAF Companies 💰

All of these startups use captured CO2 as the raw material to make fuel.

Air Company: Their AIRMADE™ SAF offers the highest GHG emission reduction of any sustainable aviation fuel in the world. They have partnerships with Jet Blue, Virgin Atlantic, and the US Air Force among others.

Twelve: They produce E-Jet® with their electrochemical reactor and proprietary catalyst. They have partnerships with Alaska Airlines, Microsoft and others.

Dimensional Energy: They make aviation fuel and other types of fuel from CO2 captured from factories or directly from the open air (DAC).

❗Extreme knowledge area❗

Just in case that wasn’t enough, here are some cool additional resources to keep exploring the subject:

AITA’s net zero plan: All the details about how the International Air Transport Association will achieve net zero by 2050.

Details of making SAF: Check out more details about how Air Company’s SAF is made and compare that to how SAF from used cooking oil is made.

Detailed analysis: The International Energy Agency’s take on the aviation industry.

That’s it for today, 1 climate tech topic in under 5 minutes.

Next week… Air-Source Heat Pumps! 🤯

If you enjoyed today’s issue, the best compliment you could pay me would be to share it with one person who you think would benefit from it :)