4 ms·

> But I wouldn't say it is a good thing we reject more than half the energy we create. The meaning of "Rejected Energy" in that graphic is obscure but it certa

> But I wouldn't say it is a good thing we reject more than half the energy we create. The meaning of "Rejected Energy" in that graphic is obscure but it certainly doesn't relate to energy which has been created and rejected. It may relate to excess capacity of fossil fuel plants (how much more they could produce if ordered to burn more fuel). The US is thankfully not "rejecting" twice as much energy as it is producing as those figures of 68.5 vs 32.7 lead you to believe. Curtailment of wind and solar generation in the US is recently around 2-4% [1] https://blog.ucsusa.org/mark-specht/renewable-energy-curtailment-101 https://blog.ucsusa.org/mark-specht/renewable-energy-curtail...

godelski 7y ago
Sfifs has an accurate link. But your comment really isn't correct. You suggest it is solely to fossil fuels. There is inherent waste to any electrical system as some of the energy produced goes into heating the wires (unless they are super conductors, but as far as I'm aware solar panels and wind farms don't use ultra high temperature super conductors. Don't even know any that exist tbh). Heat is just the simplest example, but Sfifs liked more information.
- strainer 7y ago
  > There is inherent waste to .. What has inherent waste to do with your reference to "Rejected Energy" ? What do you now understand of that graphic ? Transmission losses are generally in the range 5-10% for modern grids. Your interpretation of that ambiguous reference wrongly indicated 66% losses. Thats not reasonable and doesn't support your advice on energy storage. I suggest gaining more familiarity with the general subject before judging it.
  - godelski 7y ago
    The graphic's term for rejected energy includes a multitude of things. Thermodynamic loss is part of it but not all. It was mentioned because it is one of the easiest for people to understand. There has been another link provided that I have already referred you to that includes a more comprehensive breakdown. But yeah you can act all knowledgeable, or you can listen to the group leader of the LLNL staff that put this chart together using the same exact example I used.[0] I, again, will say that this is only a portion of the rejected energy. But thermodynamic loss (i.e. heating wires, heating your ICE engine, etc) is part of that rejected energy. [0] https://www.youtube.com/watch?v=G6dlvECRfcI https://www.youtube.com/watch?v=G6dlvECRfcI
    - strainer 7y ago
      I watched the explanation of the chart and it is still ambiguous both what it is, and its purpose. That narrator explains: "Rejected energy is the portion of energy that goes into a process and comes out generally as waste heat" - waste heat is not just as you wrote: "part" of it, it is explained to be "generally" (all of) it. Really neither of us should need to clarify the difference between "part of" and "generally all" So then "rejected energy/waste heat" can not be used or as we are saying here -"accepted" by better battery storage, which was the opinion that you brought this ambiguous chart and presentation to explain. This chart is irrelevant to battery storage. Also, most of the energy in the chart is thermo-electric derived from fossil fuel and nuclear plant. Wind turbines and solar "reject" heat energy in completely different manner and lesser degree than thermo-electric plants - it is truly nonsensical to mix the two together under the vague heading of "rejected". It makes so little sense, I do wonder about the credentials or motivation of this LLNL to educate on energy issues.
Gibbon1 7y ago
I think that most rejected energy is on the majority from thermodynamic losses. At least for electric power production. Converting heat to work has large theoretical losses (See Carnot Cycle) and loses due to engineering limits (Turbines aren't 100% efficient). Losses end up as waste heat.
- strainer 7y ago
  Rejection is an action - whatever it means in that graphic its not a thermodynamic factor. My bet is the figures shown relate to capacity factor, they have no connection to what they have been presented as - a potentially reclaimable amount. Of course the proof should lie in the article which the graphic comes from - its a very messy idea to link and debate graphics which have no clear sense without their article.
  - Gibbon1 7y ago
    Personally I'm not really very happy with that graph since it combines energy inputs into black boxes instead of groupings. Take natural gas, solar, wind, nuclear, and hydro and combine those into an electric power generation' 'fruit basket.' It makes you think you know something, but at the same time makes sure you don't know enough.
    - strainer 7y ago
      Succinctly put, thanks.

godelski 7y ago

Sfifs has an accurate link. But your comment really isn't correct. You suggest it is solely to fossil fuels. There is inherent waste to any electrical system as some of the energy produced goes into heating the wires (unless they are super conductors, but as far as I'm aware solar panels and wind farms don't use ultra high temperature super conductors. Don't even know any that exist tbh). Heat is just the simplest example, but Sfifs liked more information.

strainer 7y ago
> There is inherent waste to .. What has inherent waste to do with your reference to "Rejected Energy" ? What do you now understand of that graphic ? Transmission losses are generally in the range 5-10% for modern grids. Your interpretation of that ambiguous reference wrongly indicated 66% losses. Thats not reasonable and doesn't support your advice on energy storage. I suggest gaining more familiarity with the general subject before judging it.
- godelski 7y ago
  The graphic's term for rejected energy includes a multitude of things. Thermodynamic loss is part of it but not all. It was mentioned because it is one of the easiest for people to understand. There has been another link provided that I have already referred you to that includes a more comprehensive breakdown. But yeah you can act all knowledgeable, or you can listen to the group leader of the LLNL staff that put this chart together using the same exact example I used.[0] I, again, will say that this is only a portion of the rejected energy. But thermodynamic loss (i.e. heating wires, heating your ICE engine, etc) is part of that rejected energy. [0] https://www.youtube.com/watch?v=G6dlvECRfcI https://www.youtube.com/watch?v=G6dlvECRfcI
  - strainer 7y ago
    I watched the explanation of the chart and it is still ambiguous both what it is, and its purpose. That narrator explains: "Rejected energy is the portion of energy that goes into a process and comes out generally as waste heat" - waste heat is not just as you wrote: "part" of it, it is explained to be "generally" (all of) it. Really neither of us should need to clarify the difference between "part of" and "generally all" So then "rejected energy/waste heat" can not be used or as we are saying here -"accepted" by better battery storage, which was the opinion that you brought this ambiguous chart and presentation to explain. This chart is irrelevant to battery storage. Also, most of the energy in the chart is thermo-electric derived from fossil fuel and nuclear plant. Wind turbines and solar "reject" heat energy in completely different manner and lesser degree than thermo-electric plants - it is truly nonsensical to mix the two together under the vague heading of "rejected". It makes so little sense, I do wonder about the credentials or motivation of this LLNL to educate on energy issues.

Gibbon1 7y ago

I think that most rejected energy is on the majority from thermodynamic losses. At least for electric power production. Converting heat to work has large theoretical losses (See Carnot Cycle) and loses due to engineering limits (Turbines aren't 100% efficient). Losses end up as waste heat.

strainer 7y ago
Rejection is an action - whatever it means in that graphic its not a thermodynamic factor. My bet is the figures shown relate to capacity factor, they have no connection to what they have been presented as - a potentially reclaimable amount. Of course the proof should lie in the article which the graphic comes from - its a very messy idea to link and debate graphics which have no clear sense without their article.
- Gibbon1 7y ago
  Personally I'm not really very happy with that graph since it combines energy inputs into black boxes instead of groupings. Take natural gas, solar, wind, nuclear, and hydro and combine those into an electric power generation' 'fruit basket.' It makes you think you know something, but at the same time makes sure you don't know enough.
  - strainer 7y ago
    Succinctly put, thanks.