4 ms·

It could make sense when energy density and weight is critical, such as long range planes or some racing cars series. However I would be curious to read about

It could make sense when energy density and weight is critical, such as long range planes or some racing cars series. However I would be curious to read about the efficiency of the whole system. From the energy input at the factory to the energy output of the ICE engine, without forgetting transport and storage which fuel people love to forget about. I really doubt they are any close to a modern EV.

prennert 6y ago
"At full scale, we expect a reduction in the CO2 impact of around 85%. If you consider well-to-wheel, where we have to transport fuel, we have a global supply chain, everything around that - you have efficiency across the whole process. In a well-to-wheel consideration, it is on the same level as an electric car."
- speedgoose 6y ago
  Yes I read that sentence and I would love to see the actual numbers. They may talk about the CO2 only too.
- rtpg 6y ago
  Wait so they're claiming that, today (or roughly today), we could basically do everything through synthetic fuel (Not requiring much, if any, retooling of existing infrastructure) and basically have major CO2 reductions? This seems like a major no brainer? Especially if you start getting into "places with a bunch of sunlight but no natural petroleum can now turn into energy magnates"? This seems like an extremely powerful idea
  - konschubert 6y ago
    It is, but it's not cost-competitive right now. "E-fuel" is still much more expensive to produce than fossil fuel.
    - rtpg 6y ago
      ........oh, duh. Right. Yes. Does anyone know the current relative prices here (or any research on theoretical price limits given enough scale?) Is it possible that in our lifetimes we could see something similar to the major drops in other renewables? EDIT: From an EU report: "E-fuel costs are currently relatively high (up to 7 euros/litre) but are expected to decrease over time due to economies of scale, learning effects and an anticipated reduction in the renewable electricity price;this is expected to lead to a cost of 1–3 euros/litre (without taxes) in 2050.3The cost of e-fuels could therefore be 1–3 times higher than the cost of fossil fuels by 2050." 7 euros/litre is _very costly_, and the reduction of price is predicated on some massive drops in solar pricing which seam unreasonable. OTOH fuel is important and if there's less of it it'll be more costly! (https://www.concawe.eu/wp-content/uploads/E-fuels-article.pdf https://www.concawe.eu/wp-content/uploads/E-fuels-article.pd...)
      - azernik 6y ago
        Reduction of price isn't predicated only on massive drops in renewable energy prices - a lot of the projected drops also come from drops in the non-electricity cost. (That EU paper gives an energy efficiency of 40% for the electricity -> gasoline conversion, which my gut feeling says is pretty close to the theoretical maximum.) By my rough current calculations (average EU non-household electricity costs at 8 eurocents per kWh pre-tax, 0.12 after-tax; times 9.1kWh/L energy density of gasoline; divided by 0.4 conversion efficiency) electricity costs are only about 2.5 euros/L out of that 7 euros/L total. Could probably be brought down to 2 euros/L by concentrating production in places with plentiful renewables, like how aluminum production is currently concentrated in Iceland. That leaves 4-5 euros/L coming from non-electricity costs, where cost reductions will be easier but need to be more drastic. Even 3 euros/L is still really expensive, but only about 100-150% above the pre-pandemic peak. Anyone who doesn't really need that specific energy or energy density would still have a very strong incentive to go electric, but there would still be some viable (though more expensive) business model for mass/volume-constrained applications like air travel.
        rtpg 6y ago
- _ph_ 6y ago
  This is CO2 only and only if you count electricity as fully CO2-free, like from renewable sources. However, the total amount of electricity is way higher than an electric car would use (up to 10x). So at a time, where coal and oil are still used to generate electricity or heat houses, these synthetic fuels would even increase the CO2 impact. Only when renewables are powering mostly everything else, this becomes interesting for uses where batteries won't do (like planes, but not for cars).
_ph_ 6y ago
If you look at the electric energy used for driving the same range, the "e-fuel" powered combustion engine is like a factor of 10 off. The combustion engine alone is at least 4 times less efficient than the electric powertrain and that does not account for any inefficiencies in generating the e-fuels nor their processing and transportation. It would be a disaster to produce them while there is any coal or oil burned for electricity production. Only when they are used to replace the last usages of fossil fuels, they make sense. As you write, for planes for example.
konschubert 6y ago
Efficiency doesn't matter, cost does. Of course power costs are part of costs, but if you're able to shift your load to times of peak energy production, it's going to be very cheap.
- _ph_ 6y ago
  Efficiency matters if we want to reduce the CO2 output. As long as the grid isn't CO2-neutral, using a lot more electricity for synthetic fuels compared to electric cars means, that the electricity could have been used to replace more CO2 production elsewhere, like heating homes.
hannob 6y ago
I think this answers your question: https://twitter.com/transenv/status/899976235794788352 https://twitter.com/transenv/status/899976235794788352
- CorrectHorseBat 6y ago
  And that doesn't even include transport, storage and distribution losses for power to liquid.
- bryanlarsen 6y ago
  That's talking about hydrogen, not synthetic gasoline. Synthetic gasoline is much worse than hydrogen from an electricity efficiency perspective, but it has a huge advantage in volumetric efficiency and in existing infrastructure.
  - CorrectHorseBat 6y ago
    The third column shows synthetic gasoline.
ekianjo 6y ago
> such as long range planes or rockets

prennert 6y ago

"At full scale, we expect a reduction in the CO2 impact of around 85%. If you consider well-to-wheel, where we have to transport fuel, we have a global supply chain, everything around that - you have efficiency across the whole process. In a well-to-wheel consideration, it is on the same level as an electric car."

speedgoose 6y ago
Yes I read that sentence and I would love to see the actual numbers. They may talk about the CO2 only too.
rtpg 6y ago
Wait so they're claiming that, today (or roughly today), we could basically do everything through synthetic fuel (Not requiring much, if any, retooling of existing infrastructure) and basically have major CO2 reductions? This seems like a major no brainer? Especially if you start getting into "places with a bunch of sunlight but no natural petroleum can now turn into energy magnates"? This seems like an extremely powerful idea
- konschubert 6y ago
  It is, but it's not cost-competitive right now. "E-fuel" is still much more expensive to produce than fossil fuel.
  - rtpg 6y ago
    ........oh, duh. Right. Yes. Does anyone know the current relative prices here (or any research on theoretical price limits given enough scale?) Is it possible that in our lifetimes we could see something similar to the major drops in other renewables? EDIT: From an EU report: "E-fuel costs are currently relatively high (up to 7 euros/litre) but are expected to decrease over time due to economies of scale, learning effects and an anticipated reduction in the renewable electricity price;this is expected to lead to a cost of 1–3 euros/litre (without taxes) in 2050.3The cost of e-fuels could therefore be 1–3 times higher than the cost of fossil fuels by 2050." 7 euros/litre is _very costly_, and the reduction of price is predicated on some massive drops in solar pricing which seam unreasonable. OTOH fuel is important and if there's less of it it'll be more costly! (https://www.concawe.eu/wp-content/uploads/E-fuels-article.pdf https://www.concawe.eu/wp-content/uploads/E-fuels-article.pd...)
    - azernik 6y ago
      Reduction of price isn't predicated only on massive drops in renewable energy prices - a lot of the projected drops also come from drops in the non-electricity cost. (That EU paper gives an energy efficiency of 40% for the electricity -> gasoline conversion, which my gut feeling says is pretty close to the theoretical maximum.) By my rough current calculations (average EU non-household electricity costs at 8 eurocents per kWh pre-tax, 0.12 after-tax; times 9.1kWh/L energy density of gasoline; divided by 0.4 conversion efficiency) electricity costs are only about 2.5 euros/L out of that 7 euros/L total. Could probably be brought down to 2 euros/L by concentrating production in places with plentiful renewables, like how aluminum production is currently concentrated in Iceland. That leaves 4-5 euros/L coming from non-electricity costs, where cost reductions will be easier but need to be more drastic. Even 3 euros/L is still really expensive, but only about 100-150% above the pre-pandemic peak. Anyone who doesn't really need that specific energy or energy density would still have a very strong incentive to go electric, but there would still be some viable (though more expensive) business model for mass/volume-constrained applications like air travel.
      - rtpg 6y ago
_ph_ 6y ago
This is CO2 only and only if you count electricity as fully CO2-free, like from renewable sources. However, the total amount of electricity is way higher than an electric car would use (up to 10x). So at a time, where coal and oil are still used to generate electricity or heat houses, these synthetic fuels would even increase the CO2 impact. Only when renewables are powering mostly everything else, this becomes interesting for uses where batteries won't do (like planes, but not for cars).

_ph_ 6y ago

If you look at the electric energy used for driving the same range, the "e-fuel" powered combustion engine is like a factor of 10 off. The combustion engine alone is at least 4 times less efficient than the electric powertrain and that does not account for any inefficiencies in generating the e-fuels nor their processing and transportation. It would be a disaster to produce them while there is any coal or oil burned for electricity production. Only when they are used to replace the last usages of fossil fuels, they make sense. As you write, for planes for example.

konschubert 6y ago

Efficiency doesn't matter, cost does. Of course power costs are part of costs, but if you're able to shift your load to times of peak energy production, it's going to be very cheap.

_ph_ 6y ago
Efficiency matters if we want to reduce the CO2 output. As long as the grid isn't CO2-neutral, using a lot more electricity for synthetic fuels compared to electric cars means, that the electricity could have been used to replace more CO2 production elsewhere, like heating homes.

hannob 6y ago

I think this answers your question: https://twitter.com/transenv/status/899976235794788352 https://twitter.com/transenv/status/899976235794788352

CorrectHorseBat 6y ago
And that doesn't even include transport, storage and distribution losses for power to liquid.
bryanlarsen 6y ago
That's talking about hydrogen, not synthetic gasoline. Synthetic gasoline is much worse than hydrogen from an electricity efficiency perspective, but it has a huge advantage in volumetric efficiency and in existing infrastructure.
- CorrectHorseBat 6y ago
  The third column shows synthetic gasoline.

ekianjo 6y ago

> such as long range planes or rockets