• Dettweiler@lemmy.world
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    1 year ago

    The article doesn’t go into much detail about the production or makeup of SAF, but it sounds like a form of biodiesel/biokerosene.

      • ViciousTangerine@lemmings.world
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        1 year ago

        At least it’s hypothetically possible to create with less net carbon impact than fossil fuels. It still has a long way to go, but we’ve got to invest in things that aren’t practical right now if we ever want aviation to decarbonize.

      • Dettweiler@lemmy.world
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        1 year ago

        The most common method of making biodiesel that I know of involves fermenting farming byproducts, namely corn stalks and manure. However, it still produces CO2 when it combusts.

        • Everythingispenguins@lemmy.world
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          1 year ago

          Yeah but how much energy does it take to keep the ferment going vs how much do you get out of it? Is it scalable to meet world demand? Remember that is basically what dino oil is but with millions of years of energy input from the heat and gravity of earth.

          • Dettweiler@lemmy.world
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            1 year ago

            Fermentation is a natural process, so there’s no energy input to the process. As for output, you get almost the same energy density as standard diesel, and some excellent fertilizer. For a farming area, it’s very self sustaining. Farmers bring their excess crop waste and manure, they get fuel and fertilizer in return. Also, the methane that off-gasses during fermentation is collected and burned to supplement the power grid.

            Considering it’s mostly being used in this application, it works very well. However, I can see it falling way behind if scaled for widespread use in industrial and non-argricultural uses, where dedicated crops would be grown and harvested. Regardless, it’s a good way to cut down demand for standard fuel products for areas that can sustain a large biofuel digester.

  • Everythingispenguins@lemmy.world
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    1 year ago

    Everything I have heard about sustainable jet fuel basically points to it being a pipe dream. Bio fuel is not effectively scalable and shows no hope of being so. Where synthetic fuel just increases the energy input per unit of fuel. Neither one addresses the fact that petroleum combust engines at a high altitude have a much greater impact than ones on the ground due to the fact that they inject particulates into the stratosphere. This needs to be placed in the bin as “clean coal”

  • Eheran@lemmy.world
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    1 year ago

    If only the energy to create it was from nuclear power. But the way it is now and in the foreseeable future … this is nonsense. You lose so much energy on the way, just use regular fuel instead. Use all of that energy in processes where it does not get wasted but saves much more CO2 instead.

    • subtext@lemmy.world
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      1 year ago

      There are ways to create biofuels that are much more environmentally friendly than hydrocarbon fuels, especially when starting from a waste product such as cooking oil or biomass from clearings that would otherwise be wasted.

      Plus, it’s good to test out these not-yet-incredible sustainable fuels so that we can learn, improve, and wean off traditional hydrocarbon fuels.

      • Eheran@lemmy.world
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        1 year ago

        While making it out of existing carbon compounds, of course, removes much of the energy needed, it is still a wasteful process. There are plenty of precesses where you can burn that fuel directly, with zero additional loses. We need to drive CO2 emissions down as fast as possible.

        This is something that can be tackled in 30 years, when/if airplanes still need to burn fuel and other, lower hanging fruits are already gone.

        What they are actually doing is trying to greewash airplanes.