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Only four percent of the captured solar energy was converted into chemical energy in the syngas, although they see a route to increasing that to above 15 percen

Only four percent of the captured solar energy was converted into chemical energy in the syngas, although they see a route to increasing that to above 15 percent Seems like a fairly significant problem. The level of investment required to make this work at scale would probably be in the same ballpark as replacing the system with high speed rail wouldn't it?

zemvpferreira 4y ago
Developing carbon-neutral fuels will be a worthy use of time up until we can see people lining up to take a train from Sydney to New York. Which is to say, we better keep working on it.
bee_rider 4y ago
Replacing which system with high speed rail?
- danuker 4y ago
  I believe the jet fuel usage industry (airlines).
  - bee_rider 4y ago
    Could be. What has tripped me up is that we don't usually call it the "airline system." I think it is just a little typo but it is funny how ambiguous the result is. Airlines -- makes sense because we're talking about jet fuel, but "system" isn't usually used in the context of planes I don't think. Rail -- sort of makes sense because "railroad system" is at least a somewhat familiar expression. Maybe they are just using the size of the project as a point of comparison. Highway System -- similar to the previous, this makes most sense if it is just a comparison WRT the magnitude of the project. Highway system is of course a very common expression. Anyway this shouldn't be taken as needling at the original post or anything, it is just a little typo. The point is clearly that it is a very big project, and we have other worthy project of a similar magnitude and impact that we're not engaging in.
csours 4y ago
4 percent is VERY competitive with photosynthesis.
- marcosdumay 4y ago
  Sugarcane ethanol efficiency seems to be around 10^-11, if I'm reading this paper correctly: https://www.scielo.br/j/rca/a/GD3CT889nbKP8MZybWbTYfy/?format=pdf https://www.scielo.br/j/rca/a/GD3CT889nbKP8MZybWbTYfy/?forma... And it's the most efficient crop we produce in a large scale. But anyway, the efficiency is not very important. What is important is capital cost.
  - hinkley 4y ago
    I've heard a number of people assert that sweet potatoes are more energy dense per acre, but it looks like that may only be true if you consider complex carbs, and even then there are contenders. They may also be talking about one particular strain whereas calorie per acre lists like to say "sweet potato". Sugar beets appear to be higher than sugarcane, but they're under substantial threat and they don't like the tropics. Then there's palm oil, which is such an environmental disaster that it practically ranks as a humanitarian disaster. Then something called chufa (a nutsedge), something called sacha inchi (Inca nut, a kind of spurge), and cassava/manioch bringing up the rear barely ahead of corn. But some of these have a lot of calories in the form of oil, which means two paths are required to convert it to fuel. From a health standpoint, flooding the market with a cheap 'waste' product from a particular food process has kind of been our downfall.
    - mycall 4y ago
      > But some of these have a lot of calories in the form of oil, which means two paths are required to convert it to fuel. But isn't a calorie a unit of heat? That seems like fuel to me.
      - programmer_dude 4y ago
        Calorie is a unit of energy. Heat is just one form of energy.
throwaway09223 4y ago
High speed rail isn't a replacement for airplanes. It can supplement, but airplanes go many places that rail can't (like- across oceans)
- dredmorbius 4y ago
  So, hear me out: that might not be the case. There are a few facts which are obvious: - Powered heavier-than-air flight with large cargos and ranges will require energy storage densities on the order of present-day fossil fuels. That might be provided through continued consumption of fossil fuels (with offsets), by synthetic analogues (electricity-to-fuel, by several different routes), or at a remote stretch from biomass-derived fuels (the availabilty-vs-demand situation makes this highly unlikely). - Rail is exceptionally well-suited to electrification. Generate electricity elsewhere, feed it to the rail system. This works quite well for continental trave. Oceangoing trains have achieved limited success. That said, there are a number of reasonably traversable boundaries. The Channel Tunnel ("Chunnel") between UK and France, and Öresund between Denmark and Sweden, are two examples. Bridging or tunneling Gibralter and the Bering Strait have long been proposed, other links might be made between Malaysia and Sumatra across the Malacca Strait, along the Sunda Islands, and finally across the Timor Sea to Australia. The Timor sea is relatively shallow, at about 200m (~660 ft), though that's far deeper than the English Channel's 63m average (~200 ft). The hard crossings would be the Atlantic. There'd likely be call for two of these, one from the British Isles to a landfall in Newfoundland, another from Recife, Brazil, to Monrovia, Liberia, or Freetown, Sierra Leone. One possible option would be to construct submerged floating tunnels. Norway is considering these as options for crossing its fjords, which are too wide for traditional bridges and too deep for conventional tunnels. A floating tunnel, at a depth of about 20--50m (perhaps somewhat deeper in open ocean) could provide a potential transportation route across long stretches of open ocean. Speeds could conceivably range from lower-end high-speed rail rates to near- or beyond-supersonic speeds (with an evacuated tunnel), though I'd suspect that 200--300 kph (~120 -- 180 mph) would be more viable. For the Newfoundland-Ireland link, about 3,000 km, this equates to a 10 hour crossing. Longer than by present-day aircraft, but far faster than ship, or even airship (typically at 100-200 kph). Safety, cost, engineering, sabotage, accidents, and all manner of other issues would of course be concerns. Piloting such a project as an automated cargo channel might be one option for development. Staged links might also be developed, say, within island chains (the Faeros already have an underwater tunnel network), say from Great Britain to Ireland, and from Scotland to the Orkneys, Faeros, and Iceland, or from Newfoundland to Prince Edward Island and Greenland. But in a world of impossibilities, this is, if not especially straightforward, at least within the realm of the possible.
amluto 4y ago
4% seems okay. 15% would be amazing. The LCoE for solar PV is around $30/MWh. [0] One barrel of oil equivalent is ~1.7 MWh [0]. A 100% conversion from PV AC output to oil would give a barrel of oil for $51, which is considerably less than one pays for oil pumped out of the ground right now. But keep in mind that commercial solar plants are operating somewhere around 20% efficiency. Assuming this new technology had similar cost per unit collecting area, 4% would give a barrel of oil equivalent for not hugely more than the cost of an actual barrel of oil. 15% would cost less than a barrel of oil. [0] https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.pdf https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.... [1] https://en.m.wikipedia.org/wiki/Barrel_of_oil_equivalent https://en.m.wikipedia.org/wiki/Barrel_of_oil_equivalent
- KennyBlanken 4y ago
  ...but maximum thermal efficiency burning the fuel is 60%, and that doesn't account for the efficiency loss in transporting said fuel, either. There's a lot of lost opportunity cost here as the planet cooks. We need maximum CO2 reduction as quickly as possible, and that will come only from wind/solar and electrifying as much as possible, and carbon taxation on corporations.
  - amluto 4y ago
    All of which may be true but is irrelevant. Even if a barrel of oil gets burned just because it’s pretty and achieves 0% thermal efficiency, it still costs around $100, pumping a barrel of oil out of the ground and burning it in a bonfire still releases the same amount of CO2, and finding a way to synthesize that pretty barrel of oil for less money by direct carbon capture will be an economical way to prevent those emissions. Energy conservation by improved efficiency is great, but it’s orthogonal.
  - legutierr 4y ago
    Yes, but batteries are heavy and we need other ways to power rockets and aircraft. This process may be thermally inefficient, but on a power-to-weight ratio basis, it is more attractive than many other alternatives.
jonas21 4y ago
4% efficiency may be just fine when your energy source is free and abundant.
- theptip 4y ago
  Exactly, who cares about theoretical efficiency when we have so much surplus insolation. What matters is cost per gallon. Sure, improving efficiency may be one way to get cost down depending on how it’s done, but it’s not the end metric we should be chasing.
- eru 4y ago
  Opportunity costs are a thing..
kristopolous 4y ago
well before this announcement it was 0. So I think it's pretty great.
quickthrower2 4y ago
You would also need to make electricity generation 100% carbon free. Which we should do, but all irons in the fire is a good thing. Making the old things green “green retrofit?”’ by making the “fossil fuel” carbon neutral would be amazing.
eru 4y ago
> The level of investment required to make this work at scale would probably be in the same ballpark as replacing the system with high speed rail wouldn't it? Maybe in an ideal world the engineering challenges would be comparable. In the real world, you also have political challenges to deal with. Some countries are really bad at building new high speed rail. Or any new rail in general.
rjmunro 4y ago
Seems like a total non-problem. It doesn't matter if it captures 4%, 99% or 0.000001% of the solar energy. All that matters is the total cost of the fuel at the end is in the same ballpark as current fuel prices. This depends on the plant being economic to build and to run. For example, if you can design a cheaper version of the plant that captures only 1% of the energy of the sun, you just need 4 times as many mirrors (and the land to put them on). That might cost more than the savings on the cheaper plant design, or it might cost less. It might depend on where you are building the plant and what the land values are there and how much sunshine the area gets.

zemvpferreira 4y ago

Developing carbon-neutral fuels will be a worthy use of time up until we can see people lining up to take a train from Sydney to New York. Which is to say, we better keep working on it.

bee_rider 4y ago

Replacing which system with high speed rail?

danuker 4y ago
I believe the jet fuel usage industry (airlines).
- bee_rider 4y ago
  Could be. What has tripped me up is that we don't usually call it the "airline system." I think it is just a little typo but it is funny how ambiguous the result is. Airlines -- makes sense because we're talking about jet fuel, but "system" isn't usually used in the context of planes I don't think. Rail -- sort of makes sense because "railroad system" is at least a somewhat familiar expression. Maybe they are just using the size of the project as a point of comparison. Highway System -- similar to the previous, this makes most sense if it is just a comparison WRT the magnitude of the project. Highway system is of course a very common expression. Anyway this shouldn't be taken as needling at the original post or anything, it is just a little typo. The point is clearly that it is a very big project, and we have other worthy project of a similar magnitude and impact that we're not engaging in.

csours 4y ago

4 percent is VERY competitive with photosynthesis.

marcosdumay 4y ago
Sugarcane ethanol efficiency seems to be around 10^-11, if I'm reading this paper correctly: https://www.scielo.br/j/rca/a/GD3CT889nbKP8MZybWbTYfy/?format=pdf https://www.scielo.br/j/rca/a/GD3CT889nbKP8MZybWbTYfy/?forma... And it's the most efficient crop we produce in a large scale. But anyway, the efficiency is not very important. What is important is capital cost.
- hinkley 4y ago
  I've heard a number of people assert that sweet potatoes are more energy dense per acre, but it looks like that may only be true if you consider complex carbs, and even then there are contenders. They may also be talking about one particular strain whereas calorie per acre lists like to say "sweet potato". Sugar beets appear to be higher than sugarcane, but they're under substantial threat and they don't like the tropics. Then there's palm oil, which is such an environmental disaster that it practically ranks as a humanitarian disaster. Then something called chufa (a nutsedge), something called sacha inchi (Inca nut, a kind of spurge), and cassava/manioch bringing up the rear barely ahead of corn. But some of these have a lot of calories in the form of oil, which means two paths are required to convert it to fuel. From a health standpoint, flooding the market with a cheap 'waste' product from a particular food process has kind of been our downfall.
  - mycall 4y ago
    > But some of these have a lot of calories in the form of oil, which means two paths are required to convert it to fuel. But isn't a calorie a unit of heat? That seems like fuel to me.
    - programmer_dude 4y ago
      Calorie is a unit of energy. Heat is just one form of energy.

throwaway09223 4y ago

High speed rail isn't a replacement for airplanes. It can supplement, but airplanes go many places that rail can't (like- across oceans)

dredmorbius 4y ago
So, hear me out: that might not be the case. There are a few facts which are obvious: - Powered heavier-than-air flight with large cargos and ranges will require energy storage densities on the order of present-day fossil fuels. That might be provided through continued consumption of fossil fuels (with offsets), by synthetic analogues (electricity-to-fuel, by several different routes), or at a remote stretch from biomass-derived fuels (the availabilty-vs-demand situation makes this highly unlikely). - Rail is exceptionally well-suited to electrification. Generate electricity elsewhere, feed it to the rail system. This works quite well for continental trave. Oceangoing trains have achieved limited success. That said, there are a number of reasonably traversable boundaries. The Channel Tunnel ("Chunnel") between UK and France, and Öresund between Denmark and Sweden, are two examples. Bridging or tunneling Gibralter and the Bering Strait have long been proposed, other links might be made between Malaysia and Sumatra across the Malacca Strait, along the Sunda Islands, and finally across the Timor Sea to Australia. The Timor sea is relatively shallow, at about 200m (~660 ft), though that's far deeper than the English Channel's 63m average (~200 ft). The hard crossings would be the Atlantic. There'd likely be call for two of these, one from the British Isles to a landfall in Newfoundland, another from Recife, Brazil, to Monrovia, Liberia, or Freetown, Sierra Leone. One possible option would be to construct submerged floating tunnels. Norway is considering these as options for crossing its fjords, which are too wide for traditional bridges and too deep for conventional tunnels. A floating tunnel, at a depth of about 20--50m (perhaps somewhat deeper in open ocean) could provide a potential transportation route across long stretches of open ocean. Speeds could conceivably range from lower-end high-speed rail rates to near- or beyond-supersonic speeds (with an evacuated tunnel), though I'd suspect that 200--300 kph (~120 -- 180 mph) would be more viable. For the Newfoundland-Ireland link, about 3,000 km, this equates to a 10 hour crossing. Longer than by present-day aircraft, but far faster than ship, or even airship (typically at 100-200 kph). Safety, cost, engineering, sabotage, accidents, and all manner of other issues would of course be concerns. Piloting such a project as an automated cargo channel might be one option for development. Staged links might also be developed, say, within island chains (the Faeros already have an underwater tunnel network), say from Great Britain to Ireland, and from Scotland to the Orkneys, Faeros, and Iceland, or from Newfoundland to Prince Edward Island and Greenland. But in a world of impossibilities, this is, if not especially straightforward, at least within the realm of the possible.

amluto 4y ago

4% seems okay. 15% would be amazing. The LCoE for solar PV is around $30/MWh. [0] One barrel of oil equivalent is ~1.7 MWh [0]. A 100% conversion from PV AC output to oil would give a barrel of oil for $51, which is considerably less than one pays for oil pumped out of the ground right now. But keep in mind that commercial solar plants are operating somewhere around 20% efficiency. Assuming this new technology had similar cost per unit collecting area, 4% would give a barrel of oil equivalent for not hugely more than the cost of an actual barrel of oil. 15% would cost less than a barrel of oil. [0] https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.pdf https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.... [1] https://en.m.wikipedia.org/wiki/Barrel_of_oil_equivalent https://en.m.wikipedia.org/wiki/Barrel_of_oil_equivalent

KennyBlanken 4y ago
...but maximum thermal efficiency burning the fuel is 60%, and that doesn't account for the efficiency loss in transporting said fuel, either. There's a lot of lost opportunity cost here as the planet cooks. We need maximum CO2 reduction as quickly as possible, and that will come only from wind/solar and electrifying as much as possible, and carbon taxation on corporations.
- amluto 4y ago
  All of which may be true but is irrelevant. Even if a barrel of oil gets burned just because it’s pretty and achieves 0% thermal efficiency, it still costs around $100, pumping a barrel of oil out of the ground and burning it in a bonfire still releases the same amount of CO2, and finding a way to synthesize that pretty barrel of oil for less money by direct carbon capture will be an economical way to prevent those emissions. Energy conservation by improved efficiency is great, but it’s orthogonal.
- legutierr 4y ago
  Yes, but batteries are heavy and we need other ways to power rockets and aircraft. This process may be thermally inefficient, but on a power-to-weight ratio basis, it is more attractive than many other alternatives.

jonas21 4y ago

4% efficiency may be just fine when your energy source is free and abundant.

theptip 4y ago
Exactly, who cares about theoretical efficiency when we have so much surplus insolation. What matters is cost per gallon. Sure, improving efficiency may be one way to get cost down depending on how it’s done, but it’s not the end metric we should be chasing.
eru 4y ago
Opportunity costs are a thing..

kristopolous 4y ago

well before this announcement it was 0. So I think it's pretty great.

quickthrower2 4y ago

You would also need to make electricity generation 100% carbon free. Which we should do, but all irons in the fire is a good thing. Making the old things green “green retrofit?”’ by making the “fossil fuel” carbon neutral would be amazing.

eru 4y ago

> The level of investment required to make this work at scale would probably be in the same ballpark as replacing the system with high speed rail wouldn't it? Maybe in an ideal world the engineering challenges would be comparable. In the real world, you also have political challenges to deal with. Some countries are really bad at building new high speed rail. Or any new rail in general.

rjmunro 4y ago

Seems like a total non-problem. It doesn't matter if it captures 4%, 99% or 0.000001% of the solar energy. All that matters is the total cost of the fuel at the end is in the same ballpark as current fuel prices. This depends on the plant being economic to build and to run. For example, if you can design a cheaper version of the plant that captures only 1% of the energy of the sun, you just need 4 times as many mirrors (and the land to put them on). That might cost more than the savings on the cheaper plant design, or it might cost less. It might depend on where you are building the plant and what the land values are there and how much sunshine the area gets.