• Rivalarrival@lemmy.today
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    8 hours ago

    Liquid fuels have a couple advantages in certain scenarios. Aircraft, for example. The energy density of liquid fuels is considerably higher than batteries. Aircraft only take on as much fuel as they need to safely reach their destination. They takeoff with more weight than they can safely land, burning off fuel weight throughout their flight until they are light enough to land. Dumping fuel overboard to get down to landing weight in an emergency.

    Switch these aircraft over to batteries, and their landing weight is the same as their takeoff weight. They carry the same “fuel” weight for a regional flight as they do for a maxinum-range flight.

    • jj4211@lemmy.world
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      6 hours ago

      Well, I don’t know if the reason given is that significant, they’d just plan around the fixed weight. The issue being the energy per unit volume/weight being so far behind hydrocarbons that some applications do demand it.

      So while stationary/grid applications may lean battery since size/weight hardly matters, and EVs are debatable good enough for many scenarios, I will grant that for aircraft, boats, and some heavy equipment it’s hard to beat hydrocarbons.

      Unfortunately, on that front it has to compete with extracted hydrocarbons and doesn’t seem like it can compete as yet. It however may give hope for a more resource constrained future that the battery-hostile scenarios may still be fulfilled in a sustainable way, just at higher relative expense than today. Or they iterate on their processes to have cheaper equipment and/or increased efficiency to come closer to competitive with extracted hydrocarbons. Or a viable thing to reference for some governments mandating sustainably sourced hydrocarbons when they are really needed.

      • Rivalarrival@lemmy.today
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        20 minutes ago

        There is another major advantage…

        There is a major problem with solar and wind. Daily and seasonal variation in solar flux and wind speed forces us to size our renewable generators based on their minimum expected output. We have to install enough solar panels that we can supply our needs with only low-angle sunlight on short, winter days. But we won’t do that, because that many solar panels are about four times what we need to supply our needs on long summer days. With that much oversupply on the grid, generators won’t be able to command sufficient revenue to justify that number of panels. But we need that number of panels to supply our winter demands.

        We can match a large percentage of daily variation with sufficient grid-scale storage. We fill up reservoirs with our excess mid-day production, and run that water through hydropower plants overnight. But it is simply not possible to expand storage sufficiently to match seasonal variation.

        If we build out sufficient solar generation capacity to meet winter demand, we don’t need seasonal storage. The problem we have becomes one of seasonal oversupply. The solution to that problem is an increase in demand. We need energy-intensive products that can be brought online in daylight hours from spring to autumn, then shut down for winter.

        Producing net carbon-zero fuels could very well create part of the demand needed to justify massive expansion of our renewable power grid.