World’s first carbon-negative fuel set to be unveiled at COP24 Summit

A Swedish startup is set to unveil what it claims is the world's first carbon-negative fuel at the COP24 climate summit in Poland, in a bid to help nations decarbonise the hard-to-abate transport and heat sectors.


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The innovative new fuel, which is made entirely from elephant grass and is called NextFuel, is being posited as a viable alternative to carbon-intense cooking and heating fuels such as wood chips, coal and kerosene.

Manufactured in Austria by a startup of the same name, the fuel is made by feeding dried elephant grass into a sealed rotary drum, where oxygen is removed from the air and the material is separated into fuel and waste – a process which takes 30 minutes. Waste gases emitted during this process are captured and used to generate renewable heat or power for the manufacturing facility.

The fuel portion of the rotary drum output is then densified and pressed into briquettes before being cooled. The cool briquettes are then ready to be sold for either industrial or domestic heat and electricity production, with NextFuel claiming they can be burned in existing coal plants without the need for infrastructure upgrades.

NextFuel estimates that if a cement factory currently running on coal-fired power and heat were to switch to its alternative fuel, its annual operational carbon footprint would be reduced by 105%, making it carbon-negative. This is because elephant grass sequesters carbon as it grows and is a renewable resource, capable of growing four metres tall in three months.

“For the first time in the history of mankind, we have the ability to produce a cheap and clean copy of fossil fuel,” NextFuel’s chief executive Stefano Romano said.

“Elephant grass needs a lot of CO2 to grow, and also stores some of this in its roots below ground. In that way, it captures so much carbon from the atmosphere that it can make our entire process carbon-negative in a matter of months.”

The innovative fuel is currently produced at scale by one Austrian factory, with NextFuel having secured funding to scale-up production last year from the European Union (EU) and Austrian engineering firm Andritz. It is set to be supplied to power the first two large-scale projects by the end of 2019 – namely a cement plant in East Africa and a manufacturing facility in South America.

Fueling innovation

In the wake of repeated warnings that the world will fall short on meeting the aims of Sustainable Development Goal 7: Clean Energy for All – largely due to a lack of progress in the heat and transport sectors – companies have moved at a pace to develop innovative, low-carbon fuels in recent months.

British Airways (BA), for example, last month launched a competition aimed at encouraging researchers and innovators to develop a low-carbon jet fuel, with a £25,000 prize being offered to the winner.

Called the BA 2219 or Future of Fuels challenge and launched on Friday (30 November), the scheme challenges academics to develop a fuel capable of powering a long-haul commercial flight of up to 300 customers, generating net-zero or net-negative emissions in the process.

The move forms part of BA’s £6.5bn investment in modernising its fleet and practices in order to drive sustainability, which has already seen the airline forge a partnership with renewable fuel startup Velocys. Under the partnership, the companies will work to co-create a jet fuel from household waste and the gases it emits.

Similarly, Virgin Atlantic recently showcased an innovative jet fuel made from recycled industrial waste gases this year, using the low-carbon alternative to partially power a commercial flight from London to Orlando, Florida.

Developed as part of a partnership with LanzaTech – a firm which recycles industrial waste gases and other waste streams into ethanol-based aviation fuel – Virgin Atlantic claims that the fuel generates up to 70% fewer emissions than regular fossil jet fuel.

LanzaTech claims that the gas-capturing technology could be scaled up and retrofitted at 65% of the world’s steel mills, giving it the potential to meet 20% of the global demand for aviation fuel.

Sarah George

© Faversham House Ltd 2022 edie news articles may be copied or forwarded for individual use only. No other reproduction or distribution is permitted without prior written consent.

Comments (16)

  1. Richard Scrase says:

    Is growing and transporting quantity of elephant grass needed feasible?

    1. Tom Cunilio says:

      Elephant grass is extremely bulky when green and at the UFL in a biomass to methane project, took a huge amount of horse power to harvest it and it was slow!! There are bigger machines now that might bale the green elephant grass. Instead, we propose allowing it to frost in northern FL and southern GA, then harvest the dead, dried standing stems with smaller equipment. We are impressed with the fact that some work is being done to convert it to a coal-like material in Austria. Bravo!!!

  2. John Mathias says:

    What about the emissions resulting in transporting the fuel to Africa and South America? Would it not be better to grow and produce the fuel in these countries rather than transporting it 1,000’s of miles?

  3. Peter Haslop says:

    Where exactly are we proposing to grow this elephant grass?

    1. Tom Cunilio says:

      Lower South where we get frost. That’s a lot of acres!

  4. Colin Matthews says:

    The first Carbon negative fuel? What about Biomethane from the A.D. of manure? Would be interesting to see the energy balance between AD of elephant grass versus the calorific value of this fuel. Rather suspect you get more energy out by AD of elephant grass than by this fuel…
    Can elephant grass be grown in Africa climatically?

  5. Richard Phillips says:

    All germane comments, brushed aside by business talk.

    Besides the fuel emissions from transportation, there is the question of the heating process, (perhaps this is nuclear heat!?!?) There is even the CO2 breathed out by the workers in the process, solely due to their exertions in the process.

    So much of this nonsense disregards entirely any science or the consideration of the process in its entirety.

    And what is the molecular mechanism whereby CO2 exerts this "forcing effect" on water vapour, some sixty times the concentration of CO2 in the atmosphere?

    Richard Phillips

  6. Ian Byrne says:

    The carbon-negative aspect appears to be Elephant grass needs a lot of CO2 to grow, and also stores some of this in its roots below ground. In that way, it captures so much carbon from the atmosphere that it can make our entire process carbon-negative in a matter of months. So what happens to the carbon sequestered in the roots? Do they never rot down, releasing CO2 (or worse, methane) back to the atmosphere? Can you plant more miscanthus rhizomes in the same field that you have used before infinitely often? I suspect not…

    Colin Matthews and Richard Phillips correct, also, in that there will be associated emissions from fertiliser, transportation and processing. This article looks like greenwash to me.

  7. Torstein Lindaas says:

    I have invested in this company and the following is just what I have managed to dig up doing my due diligence. So, I’m not an expert, I’m just giving you my opinion based on what I have managed to understand until now.

    @ John Mathias
    "What about the emissions resulting in transporting the fuel to Africa and South America? Would it not be better to grow and produce the fuel in these countries rather than transporting it 1,000’s of miles?"
    You are correct, and that is indeed the plan. The Austria factory is mainly to test that the technology works in scale. So before ships can use NextFuel as fuel, or use electricity, it is indeed better to grow and produce the fuel locally, as of now this is one of the main reasons the fuel is carbon negative.

    @ Peter Haslop
    "Where exactly are we proposing to grow this elephant grass?"
    Everywhere really, but some climates are better, especially parts of Africa, South America and Asia. Generally where there is lots of sun and enough rain.

    @ Colin Matthews
    "Rather suspect you get more energy out by AD of elephant grass than by this fuel… Can elephant grass be grown in Africa climatically?"
    Have not heard about this AD process (I guess you mean anaerobic digestion). What I can tell you is that the energy content of NextFuel is 23-28 gigajoule per tonne, above brown coal and just below black coal/anthracite.
    Elephant grass grows like crazy in Africa 🙂 I talked to a girl I know that visits Kenya often and she says everybody knows about it down there.

    @ Richard Phillips
    Didn’t quite understand all your comments, but understood this: "Besides the fuel emissions from transportation, there is the question of the heating process, (perhaps this is nuclear heat!?!?) There is even the CO2 breathed out by the workers in the process, solely due to their exertions in the process."
    The heat comes from the surplus gases driven out of the grass in the torrefaction process. Only a small amount of electricity is needed in addition to this "free" heat. In the process of producing 1 ton of NextFuel, the surplus gases produce 0.85 MWH in the form of heat, while the electricity needed in addition to this, amounts to only 0.13 MWH. Total energy input is 7.07 MWH (chemical energy in the grass plus that small amount of electricity), total energy output is 5.05 MWH (chemical energy in the briquettes only, not counting the 0.85 MWH of usable heat).
    The CO2 breathed by the workers is only a very very small amount.
    Regarding fuel emissions from transportation, that is more of an issue. The longer you transport something, the more CO2 you release, so transport better get green fast.. I think it is safe to say that you can’t transport this fuel around the world and still expect the whole process to be carbon negative. It is when you both produce and use the fuel in a reasonably close distance from each other the process is CO2 negative. How close are we talking? I don’t know, but I think it is logical to expect research papers about this. This is really the million dollar question, what we all want to know.

    @ Ian Byrne: "Do they never rot down, releasing CO2 (or worse, methane) back to the atmosphere?"
    The carbon in the roots also moves to the soil around the roots. Some of it will eventually mineralize. If you do plow, "some" CO2 and methane will release back into the atmosphere, this is the same problem everywhere, both for forests and agriculture in general. If you don’t plow however, it will take a long time to leak, many decades, and nobody really knows how much is leaked and how much stays. We basically need to stay on top of this by continually planting.
    "Can you plant more miscanthus rhizomes in the same field that you have used before infinitely often?"
    Not infinitely often of course, but many times should be doable. Also, there is research on seed-based planting now.
    "there will be associated emissions from fertiliser, transportation and processing."
    You are correct. See above for the energy balance of the processing. I don’t have any numbers regarding fertiliser use and transportation. I know however that fertiliser is not very effective on miscanthus, that it grows also on marginal land without fertilizer, and that transportation at least is "in the process" of going green. For instance, I do think it is possible to power ships with NextFuel.

  8. Richard Phillips says:

    Dry elephant grass contains, per unit mass, a certain amount of heat energy, released upon complete combustion with oxygen. No more, no less. It is a founding principle of thermochemistry. There is no free lunch.

    No amount of completing the process by a variety of paths can give more energy. In fact the greater the complexity of the process, the less efficient the heat recovery becomes.

    There is nothing new in the concept of roasting complex organics; the Gas Light and Coke Company were doing this on a huge scale at the Beckton Gas Works a century ago using coal. They produced coke, town gas, and a variety of organic materials.

    The science is quite absent from this report.

    Richard Phillips

  9. Torstein Lindaas says:

    @ Richard Phillips
    "Dry elephant grass contains, per unit mass, a certain amount of heat energy, released upon complete combustion with oxygen. […] No amount of completing the process by a variety of paths can give more energy."

    Now I understand your concern, of course you are correct. But the "carbon negativity" claim is not based on pseudo-scientific claims like this, that somehow you get more energy output than energy input.

    On the contrary, there is of course less energy coming out of the process than going in, 7.07 MWH is going in, while 5.05 MWH is coming out.

    The "carbon negativity" claim rests upon basically three factors, 1.) carbon is deposited in the roots and soil below the plants, 2.) the briquette processing itself is very efficient, and 3.) if the fuel is grown and used in relatively close proximity to each other, the transport is also very energy efficient. Basically, factor 1, the depositing of carbon in the soil ("natural" CCS) outweighs the energy use of factor 2 (fuel production) and factor 3 (transport). If you grow your fuel locally, and have access to this new efficient processing technology, you get a CO2 negative fuel.

  10. Torstein Lindaas says:

    @ Richard Pillips
    Maybe you also wondered why the briquettes were at 23-28 gigajoule per ton while elephant grass itself has an energy content of approximately 18 gj/t.? To produce 1 ton of NextFuel, you need 1.56 ton of elephant grass. Basically the torrefaction process gets rid of all the unimportant stuff in the grass, and the end result is a very energy dense briquette. Only 2.5% of the energy content of the briquette originates from the use of electricity in the briquette production process, the rest originates from the grass itself!

  11. Torstein Lindaas says:

    Correction: The output is 5.51 MWH, not 5.05 MWH.

  12. Richard Phillips says:

    No, Torstein, I had not wondered at all! A major constituent of all such plant matter is cellulose (C6 H10 O5)n. Upon roasting, a great deal of the H10 O5 part will be driven off as water, leaving just the carbon, the only combustible part of the molecule. You are quite correct, this residue is just where the heat potential resides.

    In pure cellulose, over half the weight is "water", not as such, but evolved as water upon heating. Upon combustion of pure cellulose, all the heat comes from carbon, the H and O are evolved as water (and incidentally as steam, the heat of evaporation coming from the carbon, but wasted as it seldom industrially recovered ), this is common to all "carbohydrates", like sugar. The wood fired Drax power station does not operate heat recovery from the flu gas, but you must have a condensing gas central heating boiler!!

    Why not pelletise the grass on the spot, ready for direct combustion as a domestic or industrial fuel???

    As industrial fuels, biomass or biofuel, I am extremely cynical; ethanol has only half the calorific value of petrol, its addition to vehicle fuel reduces he mpg. But politicians rarely have any scientific knowledge, or the desire to acquire it.

    Richard Phillips

  13. Torstein Lindaas says:

    @ Richard Phillips
    "Why not pelletise the grass on the spot, ready for direct combustion as a domestic or industrial fuel???"
    Torrefaction before pelletization or briquetting makes the fuel less sticky, something about the fibers, it gets brittle enough to be able to be crushed into "dust bombs" that ignite at maximum efficiency in combustion chambers. Like coal do now, and regular pellets do not. Torrefied pellets/briquettes are also water resistant, like coal, while regular pellets are not (making transport and storage cheaper). Regular pellets can only work as fuel in a co-firing situation, while torrefied briquettes are so alike coal that they can be used as the only fuel. Regular pellets leaves a residue in the combustion chambers that make them somewhat unconvenient to use, it requires more maintenance and is thus more expensive.

    Regrettably I can’t give a meaningful response to your other points that I’m sure are valid, because I simply don’t have enough knowledge in chemistry. I suggest you contact the company directly, hopefully someone with technical knowledge can answer your questions, and if they do, please post what you learned here.

    You can contact them here: https://nextfuel.com/contact-us

  14. Richard Phillips says:

    Thanks for those details Torstein. There was talk of similar problems burning pelletised "leafy" material in furnaces, leaving deposits on the heat exchangers. All clouded in mystery!!!

    I still prefer nuclear fission, PWRs, with CCGT, about 80:20 And in the future we should have fast reactors, we have fuel in the cupboard, 115 tonnes of plutonium.

    Richard Phillips

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