United, Honeywell Announce New SAF Investment - AVweb

United Airlines and Honeywell have announced a multimillion-dollar investment in Alder Fuels, a company developing sustainable aviation fuel (SAF) production technologies. According to United, Alder plans to produce SAF at scale by “converting abundant biomass, such as forest and crop waste, into sustainable low-carbon, drop-in replacement crude oil that can be used to produce aviation fuel.” The stated goal of the collaboration is to produce a drop-in replacement for petroleum jet fuel.


This is a companion discussion topic for the original entry at https://www.avweb.com/ownership/fuel-news/united-honeywell-announce-new-saf-investment

So, burning a “different carbon” means the same thing as decarbonizing? That’s funny.

“National Renewable Energy Laboratory” WHAT !! What Congressional Act authorized established of still another bureaucratic entity filled with overpaid and underworked civil servants ? They’re probably all hiding in their basements yet drawing SES pay ?

So “carbon offsets” are “traditional” now?

Really? Not again! Having worked in agriculture for more than five decades, I have had more than a little exposure to the whole bio fuels circus. One of my ongoing interests is to get a technical definition of “sustainable” agriculture. I have yet to get an answer. As for waste biomass conversion to usable fuels, that was the promise of the near future at least 30 years ago when using corn and soybeans to produce ethanol and biodiesel were just temporary steps before converting to waste biomass and the use of cellulosic digestion to make ethanol, and no reasonable substitutes for light oil based products. Everyone is still waiting after decades of research that failed to provide a workable substitution of waste biomass for fuel production.
Hundreds of studies have been done to evaluate the comparative energy and resource inputs to measure whether there is a net gain in energy and carbon offsets from the conversion of crops into combustible fuels. Most of those studies (essentially all if you look outside the corn/soybean belt) show there is usually a net loss in the conversion (you put in more energy and carbon than you get back), a few that suggest a break even outcome, and very occasionally one that shows a small net gain.
The current problems with this scheme include the high energy inputs to collect, haul, and process waste biomass, the lack of direct conversion from biomass to usable fuels, and of course the carbon dioxide release from providing the heat energy and transportation. This does not include air pollution restrictions in states like CA were burning biomass has essentially outlawed by the CA air resources board.
Simply put, more green washing and woke virtue signaling by United and Honeywell, and probably a con job by Alder.

Sustainable aviation fuel is basically the only hope for long haul airline flying over the next 50 years. Flying batteries are not going to cut it, and the greenies WILL have their way. If you thought restrictions on your life for covid were bad, wait till you see the restrictions for climate change. We had better hope that SAF works.

“Hundreds of studies have been done to evaluate the comparative energy and resource inputs to measure whether there is a net gain in energy and carbon offsets from the conversion of crops into combustible fuels. Most of those studies (essentially all if you look outside the corn/soybean belt) show there is usually a net loss in the conversion (you put in more energy and carbon than you get back), a few that suggest a break even outcome, and very occasionally one that shows a small net gain.”

Flying through Brazil years ago on the way to Antarctica in a Cessna Caravan, we toured a “sustainable fuel” project. Many schemes were tried, but unlike our government, Brazil was prescient enough to mandate “You can’t USE FUEL TO MAKE FUEL–unless you can show a net gain, with processing and transportation included.” Most attempted production using sugar cane–unlike corn, it was fast growing, required little land prep or cultivation, and was cheap (best of all, you can burn the stalks to run the distiller–unlike corn). Sugar cane was the only fuel (at the time) that could meet the “net gain” mandate.

According to the latest report I can find–Reuters–Oct. 30 2019, 96% of Brazilian ethanol is from sugar cane. (unfortunately, sugar cane production won’t work in the continental U.S.) According to the same report, “Brazil to remain net ethanol importer”. I’d like to see a study showing that the U.S. actually MAKES net fuel, after subtracting the fuel used to farm the land, transport the corn, and transfer the ethanol for blending in a refinery.

I particularly liked “The current problems with this scheme include the high energy inputs to collect, haul, and process waste biomass, the lack of direct conversion from biomass to usable fuels, and of course the carbon dioxide release from providing the heat energy and transportation. This does not include air pollution restrictions in states like CA were burning biomass has essentially outlawed by the CA air resources board.
Simply put, more green washing and woke virtue signaling by United and Honeywell, and probably a con job by Alder.”

As for me, I’ll do the country a favor, and not use the stuff in the King Air I fly.

Carbon release from burning SAF does not have a carbon footprint, in the same way that the carbon you exhale does not have a carbon footprint. All the carbon you exhale was sucked from the air by plants, so it is a closed loop. So it would be with SAF.

The comment was not about SAF carbon footprint–instead, it addressed whether production of Ethanol actually DOES anything, considering the fuel used in production of Ethanol. In Brazil’s case, the only way to make it productive is using sugar cane–both for the feed stock and the stalks to run the distillery. That doesn’t appear to be an option in the U.S. (or even northern Brazil)

By the time you apply fertilizer, till the ground, harvest the corn, dry it, and transport it, (all requiring fuel) it becomes dubious that any fuel is actually being saved. I’d LIKE to see it work, but have yet to see a “closed loop example”–fuel expended vs. produced. In my childhood, people still discussed “perpetual motion machines” as a way of producing useful work–none have ever been produced. Emilie du Chatelet–"Energy cannot be created or destroyed, it can only be transformed or transferred from one form to another. For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes…"but energy is not CREATED.

Why is this so complicated?

Eat food burn Avgas/Jet A.

Never vice versa.

Well, do-gooders do not thin things though, nor have guts to walk their talk.

Ayup, apperance of doing something while feeding cronies.

Government is rotten with activists who’ve wormed their way in after being violent on streets.

And some companies are.

"Sustainable’ is a scam, based on shortage mentality.

Free people protected by defense and justice systems feed people and invent substitutes where needed.

Dig deep and you’ll find the ideology of fixed-pie economics and drive-to-the-bottom ethics that comes from denial of the effectiveness of the human mind for life - Marxism.

As different from fossil fuel. You should explain.

Fossil fuel is carbon that is stuck deep in the ground, we pull out it out and burn it in airplanes, that adds carbon to the atmosphere because otherwise it will have just stayed in the ground.

When plants or trees grow, they suck carbon out of the atmosphere to create their structure. All of the carbon in a plant or tree comes from the air. You harvest* those for food (or SAF), then you burn it in your stomach or jet engine and release carbon dioxide, but it is exactly the same amount of carbon that was in the plants, which was all taken from the atmosphere, using solar energy. So it’s a closed loop.

The harvest and processing is where things go wrong as Jim points out above. All the energy required for harvest and processing may require carbon, which means it has a carbon footprint unless you are using nuclear or solar or whatever for that part.

It wouldn’t be a perpetual motion machine because sunlight is your input to grow the crops. To be honest I don’t know enough about the state of the technology on it to say whether it is a pipe dream or not. My uninformed impression is that it is a lot more practical to reduce carbon than electric aircraft (that may not be saying much), but it is underfunded due to the aesthetics of it not being pleasing to environmentalist types, who’s preferred solution seems to be population collapse, subsistence farming, drum circles, and shivering in the dark.

Sure it does. There is a difference between carbon which was captured from the atmosphere millions of years ago, and sequestered as petroleum, versus carbon which was captured from the atmosphere in recent months by forests and crops. Spitting the former out of the back of an engine increases the net amount of carbon in the atmosphere. Spitting the latter out, returns carbon to the atmosphere from which it recently came.

Simple. It is a matter of when the carbon came out of the atmosphere, relative to human lifetimes. The carbon released by burning SAF was captured from the atmosphere in recent months by plants. The carbon released by burning petroleum was captured from the atmosphere millions of years ago. That time difference matters for the impact on the climate.

You are missing the point. The question is about what the Jet A is made from: petroleum, or “abundant biomass, such as forest and crop waste”.

That’s even funnier. Chemistry does not care. If anything the process will keep jets flying decades LONGER into the future than they otherwise would and so will increase carbon emissions in the atmosphere HIGHER than otherwise. Duh!