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Cake day: June 1st, 2023

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  • I have the same feeling.

    I think it’s due to how knowledgeable, practical, and yet pessimistic Watney’s inner monologue is through the book. It’s one thing to see something go wrong on screen (they did show all of the major issues as far as I recall, and a few minor ones too), it’s another to have the main character scientifically dissect exactly how fucked he is or will be if the next attempt at a solution fails.









  • Nope! And most hydrogen is fossil fuel (methane) derived and horribly energy inefficient. At this point it’s green washing at best.

    Edit: adding data:
    Steam-Methane Reforming (SMR) accounts for about 95% of all hydrogen production on earth. It uses a huge amount of heat, water, and methane to produce hydrogen.

    https://en.m.wikipedia.org/wiki/File:SMR%2BWGS-1.png

    For inputs:

    • 6.2MWh of Heat
    • 2.2 tons of Methane
    • 4.9 tons of pure water

    The outputs are:

    • 6 tons of CO2
    • 1.1 tons of H2

    The overall energy in vs energy out is at most 85% efficient. https://www.sciencedirect.com/science/article/abs/pii/S0016236122001867

    Hydrolysis, the main competing method, and the one most touted by hydrogen backers, accounts for about 4% of hydrogen production.
    This method takes in only pure water and electricity, but it’s efficiency is abysmal at some 52%. In every case, a modern kinetic, thermal, or chemical battery will exceed this efficiency.

    Other methods are being looked into, but it’s thermodynamically impossible for the resulting H2 to produce more energy than it takes to create the H2. So at best today we could use H2 as a crappy battery, one that takes a lot of methane to create.