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> We know of no more efficient, safe, and easily convertible storage of energy than petrol hydrocarbons. There's a lot to unpack here. "Efficiency" of a hydroc

by cjslep 7y ago

> We know of no more efficient, safe, and easily convertible storage of energy than petrol hydrocarbons. There's a lot to unpack here. "Efficiency" of a hydrocarbon doesn't make sense, unless you talk about a specific application, such as an internal combustion engine, in which case you're comparing 100+ year old technology and chemistry to relatively newer forms that simply haven't had as much light of day becoming more "efficient". Depending on what exact "efficiency" is being measured ("energy density"? Nuclear wins) will open more questions than answers. "Safety" is another interesting one. For example, regions of the world with high concentration of oil reserves, such as Venezuela and the middle East, have seen a lot of combat and instability post-WW 2. I don't think those regions are comparatively safe. While, on the other hand, fighting over wind and sunlight could happen, I wouldn't count on it. "Easily convertable storage" I don't even know what this means. Once a fuel has been converted to electricity, or kinetic energy, the storage problem is all the same.

coldtea 7y ago
>There's a lot to unpack here. "Efficiency" of a hydrocarbon doesn't make sense, unless you talk about a specific application, such as an internal combustion engine, in which case you're comparing 100+ year old technology and chemistry to relatively newer forms that simply haven't had as much light of day becoming more "efficient". Depending on what exact "efficiency" is being measured ("energy density"? Nuclear wins) will open more questions than answers. It's not that controversial. The "haven't had as much light of day becoming more "efficient" is not relevant, as the parent means among forms existing today (he said "we know of". Even if there might be a future more efficient, we don't "know of" it yet). And the measurement is usually EROI, and looks to be as the parent said: https://ruayres.files.wordpress.com/2016/09/rua-eroi-fig-5.png https://ruayres.files.wordpress.com/2016/09/rua-eroi-fig-5.p... >I don't think those regions are comparatively safe. I'd say the parent doesn't talk about that safety, it's about in applications, transport, etc. Wars happened before oil too...
- cjslep 7y ago
  You took my interpretation of efficiency in a totally unexpected direction, which is cool and let me learn something new! However I don't buy EROEI as being a good measure in a discussion about long term climate change and the wholistic picture of an energy source. EROEI is too short-term focused (on energy break even) instead of looking at the lifetime of an energy source. Oil plants and internal combustion cars need to account for the years of shipping logistical distribution and mining/drilling when looking at the lifetime of an oil plant or the lifetime of the car. Compared to the marginal energy cost of maintenance of a PV cell or wind turbine over the lifetime of those power generating structures. The EROEI at the end of the energy production lifetime may favor energy-intensive short term sunk costs with low long term marginal costs (wind and sun) instead of favoring low-entry-incumbents with high energy operating costs (oil and it's existing logistical infrastructure). So I disagree it's "not controversial" and I also think looking at EROEI for the break even point is kind of like looking at bullet holes on planes without Abraham Wald around.
  - coldtea 7y ago
    >However I don't buy EROEI as being a good measure in a discussion about long term climate change and the wholistic picture of an energy source. You're right, it's not (climate wise), as it hides the externalities. But it's my understanding that the parent meant "efficient" in the way EROEI is.
  - tetraca 7y ago
    The more we have to invest into standing up an energy source, the more cogs you have to put into simply maintaining the energy infrastructure, and the less that we have available at any given time to upkeep the rest of our logistical chains. Consider arguably the worst scenario: a civilization that has to derive all its energy needs from ethanol (which IIRC, has a 2:1 ratio). At least half of it is going to have to be dedicated to farming grain for energy and processing it into ethanol for the rest of that civilization to function. And of that non-farming half, how much of that will end up being support industry for the ethanol creating half? The amount of high technology industry that could ultimately be supported by that civilization would be dramatically lower because a much higher proportion needs to be dedicated to lower necessities.

by cjslep 7y ago

coldtea 7y ago

>There's a lot to unpack here. "Efficiency" of a hydrocarbon doesn't make sense, unless you talk about a specific application, such as an internal combustion engine, in which case you're comparing 100+ year old technology and chemistry to relatively newer forms that simply haven't had as much light of day becoming more "efficient". Depending on what exact "efficiency" is being measured ("energy density"? Nuclear wins) will open more questions than answers. It's not that controversial. The "haven't had as much light of day becoming more "efficient" is not relevant, as the parent means among forms existing today (he said "we know of". Even if there might be a future more efficient, we don't "know of" it yet). And the measurement is usually EROI, and looks to be as the parent said: https://ruayres.files.wordpress.com/2016/09/rua-eroi-fig-5.png https://ruayres.files.wordpress.com/2016/09/rua-eroi-fig-5.p... >I don't think those regions are comparatively safe. I'd say the parent doesn't talk about that safety, it's about in applications, transport, etc. Wars happened before oil too...

cjslep 7y ago
You took my interpretation of efficiency in a totally unexpected direction, which is cool and let me learn something new! However I don't buy EROEI as being a good measure in a discussion about long term climate change and the wholistic picture of an energy source. EROEI is too short-term focused (on energy break even) instead of looking at the lifetime of an energy source. Oil plants and internal combustion cars need to account for the years of shipping logistical distribution and mining/drilling when looking at the lifetime of an oil plant or the lifetime of the car. Compared to the marginal energy cost of maintenance of a PV cell or wind turbine over the lifetime of those power generating structures. The EROEI at the end of the energy production lifetime may favor energy-intensive short term sunk costs with low long term marginal costs (wind and sun) instead of favoring low-entry-incumbents with high energy operating costs (oil and it's existing logistical infrastructure). So I disagree it's "not controversial" and I also think looking at EROEI for the break even point is kind of like looking at bullet holes on planes without Abraham Wald around.
- coldtea 7y ago
  >However I don't buy EROEI as being a good measure in a discussion about long term climate change and the wholistic picture of an energy source. You're right, it's not (climate wise), as it hides the externalities. But it's my understanding that the parent meant "efficient" in the way EROEI is.
- tetraca 7y ago
  The more we have to invest into standing up an energy source, the more cogs you have to put into simply maintaining the energy infrastructure, and the less that we have available at any given time to upkeep the rest of our logistical chains. Consider arguably the worst scenario: a civilization that has to derive all its energy needs from ethanol (which IIRC, has a 2:1 ratio). At least half of it is going to have to be dedicated to farming grain for energy and processing it into ethanol for the rest of that civilization to function. And of that non-farming half, how much of that will end up being support industry for the ethanol creating half? The amount of high technology industry that could ultimately be supported by that civilization would be dramatically lower because a much higher proportion needs to be dedicated to lower necessities.