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Joined 1 year ago
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Cake day: June 16th, 2023

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  • Interesting that I learned 32.2 ft/s, but only 9.8 m/s - one less significant figure, but only a factor of two in precision (32.2 vs 32 = .6%; 9.81 vs 9.8 is only 0.1%). Here’s the fun part - as a practicing engineer for three decades, both in aerospace and in industry, it’s exceedingly rare that precision of 0.1% will lead to a better result. Now, people doing physics and high-accuracy detection based on physical parameters really do use that kind of precision and it matters. But for almost every physical object and mechanism in ordinary life, refining to better than 1% is almost always wasted effort.

    Being off by 10/9.81x is usually less than the amount that non-modeled conditions will affect the design of a component. Thermal changes, bolt tensions, humidity, temperature, material imperfections, and input variance all conspire to invalidate my careful calculations. Finding the answer to 4 decimal places is nice, but being about to get an answer within 5% or so in your head, quickly, and on site where a solution is needed quickly makes you look like a genius.


  • My only reason to believe that is not what is happening is that China, and the Chinese, are too smart to using coal as a peaking or emergency source of power. The only thing worse than coal for peaking is nuclear. Oil, Gas, and hydro are all much better for short-to-mid term peaking and batteries - something they’re very good at and have vast resources for - are perfect for short term emergency/failover loads. I believe (without documentation) that they are building extra capacity for the possibility of another expansion - the incubation of so many “third world” economies and partnerships across Asia and Africa to spur demand for their domestic production. If they don’t use it, it was a jobs program; if they find they need it, they will accept short term cash and economic power for a worsening of the world environment. In a way, the largest communist country on earth is also the largest capitalist power. Ironic.


  • his past year, China couldn’t run their hydro at peak capacity because of a drought.

    Well, yes. The simple facts we have are that fossil fuel use is up. What happens next year will be speculation, but what we know is that they are using more coal this year, and they are hedging their future bets by building out their coal generation capacity. So if climate change means a further drop in hydro output, or more cloud cover where they install solar, or they need to make more power than they’re installing because the world wants more steel (I’m in the building industry and steel supply is still a bit tight) - they can start belching out a massive amount of CO2.

    Only time will tell - and I hope you turn out to be the one who is right :-)




  • I presume “decline” is used in the percentage sense and not the absolute sense. If the total power amount of carbon-based fuel generation plants is increasing, and the fuel is coal ©, then the carbon emissions must go up in an absolute sense. But the rapid deployment of non-carbon fuel power sources are increasing faster than the the carbon based, so percentage will go down. Am I reading this wrong?

    Also, in a linked article: "And, as Myllyvirta highlights, numbers in the communique stating that coal consumption rose 4.3% in 2022 and total energy use rising 2.9% “appear to contradict weak or falling industrial output”

    So consumption of coal - the most carbon-producing fuel - rose in 2022, and according to this article their energy consumption jumped again after Covid restrictions were lifted this year. Renewable installation is rising faster than carbon installation (280GW installed this year vs 136GW of coal “under construction”). The data given in these articles seems intentionally inconsistent, from annual installation (only given for renewable) to total capacity (only given for future Coal). One has to wonder if The Guardian is running their articles through some kind of Donald Trump AI filter to ensure that no verifiable content gets printed.








  • Marketing: We need to defend this - what’s something people are really excited about?

    Engineer: Stainless steel; you can’t make a good stainless without nickel

    Salesman: Oooh - I know! How about nickels? Everybody loves nickels and their worth 5 cents each!

    Engineer:

    Marketing:

    Intern: You know, they use nickel in battery packs for electric cars

    Marketing: Oh, right - everybody likes electric cars. Green and vroom-vroom, I love it!

    Engineer: You know that electric cars don’t go vroom-vroom, right?

    Marketing: I’m going with electric cars, it’s a feel-good use people will get behind.