• eleitl@lemmy.mlM
    link
    fedilink
    English
    arrow-up
    7
    arrow-down
    1
    ·
    10 months ago

    Very nice pedagogically.

    I wonder when we’ll start seeing first results of current lack of nitrogen fertilizer production. Water electrolysis hydrogen from renewable is too expensive. But it’s the only game in town in the long run.

    • maketotaldestr0i@lemm.eeOPM
      link
      fedilink
      English
      arrow-up
      3
      ·
      10 months ago

      There has been a number of “we got this” claims for green nitrogen production that ive followed for some years and tried to get data from but every one of them has narrative to spew and zero math to give an idea of energy cost of per unit of N which lights up my bullshit meter. an example of a company https://jupiterionics.com/our-technology/ though i see they changed their website since last time i checked so maybe their is data now. The fact that none of them will give figures to compare makes me pretty sure they are all worse than Birkeland–Eyde process which is not dependent on fossil fuels in the same way as haber bosch process.

      1 lb nitrogen per 43lbs dry corn grain, 1lb nitrogen per 150lb potatoes production.

      According to wikipedia With 1kwh in birkland eyde process you get about 60grams of Nitric acid so ?13.333? of elemental N (if i did the chemistry conversions right).

      So a 1kwh solar array in oregon would get about 5kwh per day in the spring ramping up to 7.5kwh in summer which happens to track plant N needs since its light dependent . so if we just use a 6kwh average for may-september growing season we get 900kwh x 13 = 11700g = 11.7 kilos elemental N which is 25.13 kilos urea or 33.4 kilos ammonium nitrate (check my chemistry)

      Bringing us (sorry switching back to lbs instead of kilos again) a solid 25lbs of N which is good for about 1075lb of corn grain or 3750lb of potato which is adequate for a single persons yearly calorie rations.

      So overall i think it could make economic sense as a survival enhancement to get a cheap 1kw used solar panel array connected to a home brew Birkeland–Eyde nitric acid generator bubbling through a limestone/dolomite pea gravel bubble barrel (calcium nitrate) fed to a mazzei injector to fertigate a home self sufficiency garden.

      Thoughts anyone?

      amortized across 25+ years in food value versus retail it pays for itself many time over . costs versus just buying 1 ton pallet of 20 kilo bags of fertilizer , maybe not as advantageous economically but certainly a cooler project than explaining why you have an entire ton of ammonium nitrate in the shed

    • maketotaldestr0i@lemm.eeOPM
      link
      fedilink
      English
      arrow-up
      3
      ·
      10 months ago

      Nitrogen fertilizer production consumes about 5 per cent of the global natural gas supplies, which arent supposed to peak until 2034ish, so we probably have a good decade runway ahead still

      • eleitl@lemmy.mlM
        link
        fedilink
        English
        arrow-up
        3
        ·
        10 months ago

        I seem to recall some 2% as the figure. Right now nitrogen fixation has shifted to locations with lowest natgas/energy prices. Overall production volume is lower and the price is high enough to price out poorer customers. So this should reduce total yield and protein quality. It might already be happening.

        Peak tight resource extraction is murky, Art Berman got sidelined with higher rig productivity and lower price and rig count before. I am agnostic at the moment.

        • maketotaldestr0i@lemm.eeOPM
          link
          fedilink
          English
          arrow-up
          3
          ·
          10 months ago

          i believe the 2% figure is global agricultures total energy usage out of total global energy supply. the 5% is more specifically fertilizer from natural gas supply.

          fertilizer prices have come back down again, but yeah any time price rises the cost rapidly prices out marginal producers and the consumers at the bottom of the socioeconomic ladder.

          I know eurozone fertilizer production seems utterly fucked without access to the cheap russian gas. USA is booming with pipelines and new ammonia production facilities .