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The argument that 'everyone has been wrong so far' is not a solid one. The green revolution was basically pouring oil (pesticides) and pumping natural gas (fer

The argument that 'everyone has been wrong so far' is not a solid one. The green revolution was basically pouring oil (pesticides) and pumping natural gas (fertilizer) into the fields. As oil flow rates are peaking this is an increasingly costly process, and as EROEI lowers on what's left we run into more problems. Same for NPK inputs - they are getting harder and more expensive (both $$ and energy) to extract. To a lesser degree (but of growing concern) all resources - we now mine 3-5% ores where we once mined 70% ores for example. Exponential curves don't go on forever in the real world. Ideas don't replace energy, nor do they replace resources. Saying it hasn't happened yet so those who are worried about it are wrong is naive and logically flawed.

ars 14y ago
Oil is not pesticides and natural gas is not fertilizer. (Why do you think they are?) Both of those are energy, and you need energy to make pesticides and fertilizer - but you need ANY energy, it doesn't matter what kind. So even if oil flow rates were peaking (which they aren't), it wouldn't matter as long as we had another source of energy, and we do.
- Thrymr 14y ago
  Most of the hydrogen used in the Haber process (to produce ammonia for fertilizer) comes from methane (natural gas). Most of the hydrocarbons used to produce commercial pesticides come from petroleum. They are not just energy sources, they are raw materials.
  - ars 14y ago
    They only get hydrogen that way because methane is also an energy source. It would be trivial to replace it with water plus external heating if you had some other energy source. You can get hydrocarbons anywhere, petroleum is convenient, but certainly not required. The raw material of fertilizer is nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Methane is none of those - it's just a carrier for nitrogen. Same with pesticides, they are organic molecules so need hydrocarbons, but you can use any hydrocarbon, from trees, grass, whatever. Oil is cheap, so they use it, but it would not be a big problem if you had to use something else.
    - richardjordan 14y ago
      It's that IF that's the problem... We can solve a lot of the world's problems, not just this one, if we can find an energy source with the kind of lifetime EROEI (energy return on energy investment) characteristics of petroleum based fuels. The non-trivial problem being we have yet to discover anything close to that. NPK inputs are energy intensive (check out Phosphorous mining). 95% of the world'a food supply is dependent on petrochemical based inputs of which we are starting to see a decline in availability. If you can show me ANY process to turn trees into pesticides as you suggest in any kind of energy efficient manner I'm open to revising my opinion, and would probably change careers to focus on that industry as I think it'd be a world changer. However I think you are very wide of the mark on the science in making such a suggestion.
      - ars 14y ago
        Petroleum isn't magic. It's just mixed random hydrocarbons. Use http://en.wikipedia.org/wiki/Gasification http://en.wikipedia.org/wiki/Gasification to turn the tree into useful feedstock gases, then use the http://en.wikipedia.org/wiki/Fischer-Tropsch_process http://en.wikipedia.org/wiki/Fischer-Tropsch_process to turn those gases into the exact same mixed hydrocarbons found in petroleum.
        richardjordan 14y ago
        Please. You keep saying things like this but it's nonsense. Do some homework: https://en.wikipedia.org/wiki/Energy_returned_on_energy_invested https://en.wikipedia.org/wiki/Energy_returned_on_energy_inve... I have been respectful of your comments in this thread so please don't see me as being overly harsh, but you are saying things that are nonsensical. We don't love hydrocarbons because of what they are but because the energy we get from them exceeds the energy necessary to produce them so they're a net source of energy, and not by a little - oil is something like 100:1 EROEI positive. Nothing comes close in terms of lifecycle EROEI.
        ars 14y ago
        First you said that we need them to make pesticides, and replacing them would be impossible. So I showed you how to make pesticides without oil. And now they are for energy, and the pesticides doesn't actually matter. Talk about moving the goal posts. Look, of course oil is used for energy, no one disputes that. The method of making synthetic hydrocarbons is not as efficient as just finding it in the ground. But it is a net positive for energy, and in a world where it's hard to find oil it would work just fine - especially if all you needed was pesticides and other organic chemicals. If we run out of energy we are going to be in much bigger trouble than pesticides - but we won't run out of energy, because if we come close then public sentiment will shift and nuclear power will be OK again - and we have at least 10,000 years worth of that - at a minimum. This article is about population, and your claim (I think), is that we can't actually sustain as much population as we think because we're going to run out of oil AKA energy. Except you are wrong about that, just like you were wrong about "If you can show me ANY process to turn trees into pesticides" - which I did. We have many many options for energy besides oil, and we can sustain our population just fine.
- DavidAdams 14y ago
  Nearly all pesticides are made from oil: http://en.wikipedia.org/wiki/Petroleum http://en.wikipedia.org/wiki/Petroleum Many synthetic fertilizers are synthesized directly from natural gas: http://en.wikipedia.org/wiki/Fertilizer http://en.wikipedia.org/wiki/Fertilizer
  - ars 14y ago
    See my reply here: https://news.ycombinator.com/item?id=5548378 https://news.ycombinator.com/item?id=5548378 Synthetic fertilizers are not synthesized from natural gas - they can't be. Methane has no elements that plants need. Methane is just a carrier for the elements acquired elsewhere.

ars 14y ago

Oil is not pesticides and natural gas is not fertilizer. (Why do you think they are?) Both of those are energy, and you need energy to make pesticides and fertilizer - but you need ANY energy, it doesn't matter what kind. So even if oil flow rates were peaking (which they aren't), it wouldn't matter as long as we had another source of energy, and we do.

Thrymr 14y ago
Most of the hydrogen used in the Haber process (to produce ammonia for fertilizer) comes from methane (natural gas). Most of the hydrocarbons used to produce commercial pesticides come from petroleum. They are not just energy sources, they are raw materials.
- ars 14y ago
  They only get hydrogen that way because methane is also an energy source. It would be trivial to replace it with water plus external heating if you had some other energy source. You can get hydrocarbons anywhere, petroleum is convenient, but certainly not required. The raw material of fertilizer is nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Methane is none of those - it's just a carrier for nitrogen. Same with pesticides, they are organic molecules so need hydrocarbons, but you can use any hydrocarbon, from trees, grass, whatever. Oil is cheap, so they use it, but it would not be a big problem if you had to use something else.
  - richardjordan 14y ago
    It's that IF that's the problem... We can solve a lot of the world's problems, not just this one, if we can find an energy source with the kind of lifetime EROEI (energy return on energy investment) characteristics of petroleum based fuels. The non-trivial problem being we have yet to discover anything close to that. NPK inputs are energy intensive (check out Phosphorous mining). 95% of the world'a food supply is dependent on petrochemical based inputs of which we are starting to see a decline in availability. If you can show me ANY process to turn trees into pesticides as you suggest in any kind of energy efficient manner I'm open to revising my opinion, and would probably change careers to focus on that industry as I think it'd be a world changer. However I think you are very wide of the mark on the science in making such a suggestion.
    - ars 14y ago
      Petroleum isn't magic. It's just mixed random hydrocarbons. Use http://en.wikipedia.org/wiki/Gasification http://en.wikipedia.org/wiki/Gasification to turn the tree into useful feedstock gases, then use the http://en.wikipedia.org/wiki/Fischer-Tropsch_process http://en.wikipedia.org/wiki/Fischer-Tropsch_process to turn those gases into the exact same mixed hydrocarbons found in petroleum.
      - richardjordan 14y ago
        Please. You keep saying things like this but it's nonsense. Do some homework: https://en.wikipedia.org/wiki/Energy_returned_on_energy_invested https://en.wikipedia.org/wiki/Energy_returned_on_energy_inve... I have been respectful of your comments in this thread so please don't see me as being overly harsh, but you are saying things that are nonsensical. We don't love hydrocarbons because of what they are but because the energy we get from them exceeds the energy necessary to produce them so they're a net source of energy, and not by a little - oil is something like 100:1 EROEI positive. Nothing comes close in terms of lifecycle EROEI.
        ars 14y ago
        First you said that we need them to make pesticides, and replacing them would be impossible. So I showed you how to make pesticides without oil. And now they are for energy, and the pesticides doesn't actually matter. Talk about moving the goal posts. Look, of course oil is used for energy, no one disputes that. The method of making synthetic hydrocarbons is not as efficient as just finding it in the ground. But it is a net positive for energy, and in a world where it's hard to find oil it would work just fine - especially if all you needed was pesticides and other organic chemicals. If we run out of energy we are going to be in much bigger trouble than pesticides - but we won't run out of energy, because if we come close then public sentiment will shift and nuclear power will be OK again - and we have at least 10,000 years worth of that - at a minimum. This article is about population, and your claim (I think), is that we can't actually sustain as much population as we think because we're going to run out of oil AKA energy. Except you are wrong about that, just like you were wrong about "If you can show me ANY process to turn trees into pesticides" - which I did. We have many many options for energy besides oil, and we can sustain our population just fine.
DavidAdams 14y ago
Nearly all pesticides are made from oil: http://en.wikipedia.org/wiki/Petroleum http://en.wikipedia.org/wiki/Petroleum Many synthetic fertilizers are synthesized directly from natural gas: http://en.wikipedia.org/wiki/Fertilizer http://en.wikipedia.org/wiki/Fertilizer
- ars 14y ago
  See my reply here: https://news.ycombinator.com/item?id=5548378 https://news.ycombinator.com/item?id=5548378 Synthetic fertilizers are not synthesized from natural gas - they can't be. Methane has no elements that plants need. Methane is just a carrier for the elements acquired elsewhere.