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> For each energy source, we pulled out the figure for LUIE (land-use intensity of energy), i.e. the amount of land required to produce a given amount of electr

> For each energy source, we pulled out the figure for LUIE (land-use intensity of energy), i.e. the amount of land required to produce a given amount of electricity. Turning bio-mass into electricity comes with a lot of losses. If the desired product is fuel, the numbers for bio-mass are a lot better, and the numbers for all other sources that first produce electricity are a lot worse, because turning electricity into fuel comes with a lot of losses.

plaidfuji 4y ago
> turning electricity into fuel comes with a lot of losses. This is true, but when generating fuel, the end goal is usually to move a vehicle X miles. Now that electric cars are nominally competitive with ICE vehicles, the metric should be something more like “land required to drive a truck X miles/year” - and assume the best of either electric vehicle efficiency or ICE efficiency, not force an arbitrary electrical->chemical conversion for the metric’s sake. Biofuels probably wouldn’t look like as much of an outlier as they do here, but I would still wager that they’re among the least efficient options.
- pfdietz 4y ago
  Biofuels would be focused on applications where electrical vehicles would suck, such as aircraft.
  - adgjlsfhk1 4y ago
    Tran-oceanic shipping and long haul airplanes are the 2 places where biofuel theoretically has some merit, but it still has the problem that it is about 25% worse than just using fossil fuels.
    - pfdietz 4y ago
      That 25% argument was addressed elsewhere in the comments.
      - concordDance 4y ago
        It would be helpful to include a link.
- cbsmith 4y ago
  > Biofuels probably wouldn’t look like as much of an outlier as they do here, but I would still wager that they’re among the least efficient options. I wouldn't wager because it's not a simple yes or no type question. There's a lot of ambiguities even in the analysis behind the graph presented in the article, but when it comes to fuels vs. batteries, it gets even more insane. Fuels have a weight advantage over batteries that gets magnified as the weight and range of the vehicle increases... and there's a lot of variance within fuels too. So, while an electric bicycle is going to be a no-brainer over a motorcycle for pretty much any scenario, it can be quite the opposite for something like a commercial truck. I keep coming back to the economist argument that if we just captured the externalities related to climate change, we avoid having these discussions and simply look at the price of things... but of course, that's the hard part in all these discussions.
enkid 4y ago
But he address the fact that it's actually worse from a carbon standpoint than gasoline. That added to the other environmental impacts associated with agriculture makes it clear it's still a worse choice than straight gasoline. Not only does it not help, it actively makes the problem worse.
- pfdietz 4y ago
  That was for ethanol from corn. Most of the carbon in the corn plants doesn't turn into fuel in that system. Even if cellulose could be converted, a great deal would still be lost in CO2. A land-efficient biomass fuel system would convert all the carbon in the biomass into fuel. This would require adding extra hydrogen, particularly if you want hydrocarbon fuels, since the oxygen in the biomass has to be carried off somehow. The hydrogen could be sourced from solar or wind by electrolysis.
  - colechristensen 4y ago
    I am not a huge fan of ethanol fuel but the leftovers from fermentation aren’t waste, they’re sold as cattle feed. So the land utilization is split between products and it wouldn’t necessarily be better if the corn to fuel concession was higher.
  - enkid 4y ago
    Is there a better alternative?
    - pfdietz 4y ago
      I've been interested in this company's technology for a long time: https://www.virent.com/ https://www.virent.com/ In any biomass technology with a CO2 waste stream, the CO2 can be converted to hydrocarbon fuel by Fischer-Tropsch, if you have additional hydrogen. In the post fossil fuel age, there will be an entire biochemical industry that converts biomass to chemicals now obtained from fossil fuels. Some of these processes will look a lot like things developed for the petrochemical industry. All the carbon going into landfills now will instead be fed into this industry.

plaidfuji 4y ago

> turning electricity into fuel comes with a lot of losses. This is true, but when generating fuel, the end goal is usually to move a vehicle X miles. Now that electric cars are nominally competitive with ICE vehicles, the metric should be something more like “land required to drive a truck X miles/year” - and assume the best of either electric vehicle efficiency or ICE efficiency, not force an arbitrary electrical->chemical conversion for the metric’s sake. Biofuels probably wouldn’t look like as much of an outlier as they do here, but I would still wager that they’re among the least efficient options.

pfdietz 4y ago
Biofuels would be focused on applications where electrical vehicles would suck, such as aircraft.
- adgjlsfhk1 4y ago
  Tran-oceanic shipping and long haul airplanes are the 2 places where biofuel theoretically has some merit, but it still has the problem that it is about 25% worse than just using fossil fuels.
  - pfdietz 4y ago
    That 25% argument was addressed elsewhere in the comments.
    - concordDance 4y ago
      It would be helpful to include a link.
cbsmith 4y ago
> Biofuels probably wouldn’t look like as much of an outlier as they do here, but I would still wager that they’re among the least efficient options. I wouldn't wager because it's not a simple yes or no type question. There's a lot of ambiguities even in the analysis behind the graph presented in the article, but when it comes to fuels vs. batteries, it gets even more insane. Fuels have a weight advantage over batteries that gets magnified as the weight and range of the vehicle increases... and there's a lot of variance within fuels too. So, while an electric bicycle is going to be a no-brainer over a motorcycle for pretty much any scenario, it can be quite the opposite for something like a commercial truck. I keep coming back to the economist argument that if we just captured the externalities related to climate change, we avoid having these discussions and simply look at the price of things... but of course, that's the hard part in all these discussions.

enkid 4y ago

But he address the fact that it's actually worse from a carbon standpoint than gasoline. That added to the other environmental impacts associated with agriculture makes it clear it's still a worse choice than straight gasoline. Not only does it not help, it actively makes the problem worse.

pfdietz 4y ago
That was for ethanol from corn. Most of the carbon in the corn plants doesn't turn into fuel in that system. Even if cellulose could be converted, a great deal would still be lost in CO2. A land-efficient biomass fuel system would convert all the carbon in the biomass into fuel. This would require adding extra hydrogen, particularly if you want hydrocarbon fuels, since the oxygen in the biomass has to be carried off somehow. The hydrogen could be sourced from solar or wind by electrolysis.
- colechristensen 4y ago
  I am not a huge fan of ethanol fuel but the leftovers from fermentation aren’t waste, they’re sold as cattle feed. So the land utilization is split between products and it wouldn’t necessarily be better if the corn to fuel concession was higher.
- enkid 4y ago
  Is there a better alternative?
  - pfdietz 4y ago
    I've been interested in this company's technology for a long time: https://www.virent.com/ https://www.virent.com/ In any biomass technology with a CO2 waste stream, the CO2 can be converted to hydrocarbon fuel by Fischer-Tropsch, if you have additional hydrogen. In the post fossil fuel age, there will be an entire biochemical industry that converts biomass to chemicals now obtained from fossil fuels. Some of these processes will look a lot like things developed for the petrochemical industry. All the carbon going into landfills now will instead be fed into this industry.