• JohnDClay@sh.itjust.works
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    1 year ago

    I was saying it seems to make sense to use hydrogen as an intermediate step before you can put in all the infrastructure for overhead wires. If Germany is just using electric engines plus diesel engines now, instead of hydrogen engines, then there’s still emitting a whole lot more than they would otherwise. Even if it is cheaper.

    • Cethin
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      1 year ago

      There’s no way Hydrogen in Germany would be more green than diesel. It’d just be greenwashing. You’d need to make electricity to make hydrogen, store it and transport it, then turn it back into electricity (that’s how a hydrogen engine works, not by burning it). In the mean time, Germany is increasing it’s production of dirty energy, so the hydrogen production would have to be done with dirty energy. There’s no way that process is more efficient than just using diesel directly.

      It might be better somewhere else, but not in Germany.

      • JohnDClay@sh.itjust.works
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        1 year ago

        You don’t need to use the standard grid energy. You can use off peak power rates in areas with a lot of wind, so it’d use the otherwise unusable energy. Or you could disconnect from the grid entirely. But the power source is absolutely a concern.

        What would the co2 trade off look like between diesel and hydrogen? Diesel you’d have a constant co2 per mile, whereas hydrogen would have higher kwh efficiency, but high conversion inefficiency, then some percentage of the energy emits co2 at a certain rate. I don’t have time to crunch the numbers now, but I would be surprised if hydrogen was more ghg intensive.

        • Cethin
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          1 year ago

          Or you could disconnect from the grid entirely.

          The off peak usage, sure. This though? How would that be green? You could spend the same money to install solar, wind, whatever and take dirty energy off the grid. That’s the point is you need to use energy to make it, when instead that energy could remove dirty energy. It’s greenwashing. It’s not removing demand for dirty energy, its just increasing overall energy demand.

          • JohnDClay@sh.itjust.works
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            1 year ago

            Increasing energy use compared to diesel? If you count the energy in the diesel, I’m pretty sure hydrogen would use less. But I think what matters over all is the total co2 emitted per mile, including generation.