You can easily find me on GitHub, StackOverflow (and etc. related stackexchange sites), LinkedIn, and of course my own website.

  • 0 Posts
  • 25 Comments
Joined 3 years ago
cake
Cake day: May 16th, 2022

help-circle






  • RoboHack@lemmy.catoScience*Permanently Deleted*
    link
    fedilink
    arrow-up
    2
    ·
    2 years ago

    I haven’t looked at this study yet in detail (but I will when I have time), however I’m suspecting they’ve missed or ignored some huge sectors.

    There is at least one study that suggests effectively the opposite for just Australia, and Aus is a particularly good example because it actually has relatively low industrial energy use.

    https://theconversation.com/itll-be-impossible-to-replace-fossil-fuels-with-renewables-by-2050-unless-we-cut-our-energy-consumption-189131

    Compare Australia’s energy flow graph with that of China and the USA and then try to work out the numbers to show just how much new solar+wind+storage will need to be built to fill in the difficult-to-electrify but major sectors and you’ll see just how big the problem is:

    https://flowcharts.llnl.gov/commodities/energy

    I think the world might be able to largely electrify ground and sea transport, and maybe home heating, together with a net-zero electrical grid, all by 2050. However that’s just a small portion of the total energy use in the world.

    It is also important to realize that there will be no peaks or valleys in the electricity demand graphs once all things are electrified (or even once just ground transport is electrified). This means all intermittent power generation has to include sufficient storage and or other backing for when it isn’t working.

    From my own back-of-the-envelope calculations I find that renewables (other than hydro-electric) are at least one order of magnitude, and probably two orders of magnitude too far behind the fossil-fuel powered sector, while storage is at least three orders of magnitude too far behind. I think nuclear power will have to play a much larger part, but it can just barely make it to the table in large enough amounts by 2050, and it also requires some re-engineering to have a closed fuel cycle and use new fuels like thorium, and much of this is still research (though CANDU reactors have already been demonstrated to burn thorium efficiently).

    There is also quite a lot of speculation in just exactly how some huge sectors can be electrified. Cement and steel being two. Sure there’s green steel being produced now, but China is also still building and planning to build numerous new coal-fired blast furnaces and smelters that may have to all continue running until after 2050. Also there are as yet no 100% net-zero commercial airline flights to book, and none on the near horizon either.

    Add politics and capitalism to the matter, especially in the USA and China, and it seems very unlikely that the world will achieve net-zero emissions by 2050.





  • RoboHack@lemmy.catoScience*Permanently Deleted*
    link
    fedilink
    arrow-up
    7
    ·
    2 years ago

    The headline is hugely misleading. It’s a long and complicated article, covering a very complicated subject.

    “Embodied emissions can be devilishly difficult to accurately quantify, and nowhere are there more complexities and uncertainties than with EVs.”

    That sentence from the article should have been the headline, but perhaps then it wouldn’t have attracted the same kind of attention.


  • RoboHack@lemmy.catoScienceCellular intelligence
    link
    fedilink
    arrow-up
    2
    ·
    2 years ago

    Perhaps a better way to express the point I was trying to make is to say that if you want to talk about most efficient then you have to define the requirements for what that means. Nature’s “most efficient” may not be man’s most efficient. That video was the “most” egregious misuse of defining efficiency since it ignored most (all but location) information about the requirements for defining interconnections between locations! Ignorance at its best.



  • RoboHack@lemmy.catoScienceCellular intelligence
    link
    fedilink
    arrow-up
    2
    ·
    2 years ago

    No, definitely not “most efficient”. Nature is only rarely extremely efficient at any one thing, but given the complexity of the environment nature (through evolution) has managed to be “good enough” at a wide variety of things – often using tradeoffs that we fail to see even after looking a thousand times to deal with issues we have not yet begun to fathom. You’re right that many millions of generations, through evolution, can often find ways that are “more efficient” than what we humans have thought of in a just a relatively few iterations so far.

    Believing that the “path” something in nature discovers is “most efficient” is pure unfounded faith and it is a grave mistake to “believe” that there is not some “more efficient” way to do something; with all the the ifs ands and buts all hanging and hinging on defining what is most important to any given circumstance at any given time.

    BTW, comparing paths found between arbitrarily spaced nodes on an otherwise featureless medium decries all the issues of geography, physics, engineering, economy, personalities, and even other simple historical influences (the latter two of which would be next to impossible to model), in the creation of a rail system in the real world, and thinking that the former is better in any way than the latter is the height of hubris based on unscientific belief systems.