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Earlier quoted context omitted.
https://acoup.blog/2022/07/15/collections-logistics-how-did-... The Tyranny of the Wagon
Are you making a reference to the Tyranny of the Rocket Equation? The Earth's gravity is so large that it's almost at the limit of chemical rockets. A typical rocket is 90% propellant by mass, 8% structure and 2% payload.
Earlier quoted context omitted.
So basically a very friendly version of the rocket equation.
There is no mention of the amount of fuel used to transport the fuel in the article. From what I know it’s a tiny fraction: boats are efficient at transporting stuff (slowly)
> Fossil fuels are roughly 40% of maritime tonnage, but in the model they represent about half of maritime freight energy because coal, oil, and gas are mostly long-haul bulk trades. Moving a ton of scrap metal a short distance and moving a ton of oil or LNG across oceans are not the same transport-energy problem, even if both show up as one ton in a cargo table.
as being exactly what was being talked about... more fuel is spent on transporting fuel due to distance it travels.
but your comment made me re-visit (i.e. more closely skim...) the article, and it's really about: "as the demand for fossil fuels is projected to decrease, (1) less long-haul shipping is needed and (2) a greater fraction of shipping will be short-haul, which will be practical for other types of freight fueling (i.e. what's shown in the figure at the top of the article)
I have no sense of how realistic the figure is. For example, I don't know the current projections for decline of fossil fuel demand over ?? year timeframe.
Earlier quoted context omitted.
https://acoup.blog/2022/07/15/collections-logistics-how-did-... The Tyranny of the Wagon
Are you making a reference to the Tyranny of the Rocket Equation? The Earth's gravity is so large that it's almost at the limit of chemical rockets. A typical rocket is 90% propellant by mass, 8% structure and 2% payload.
What the hell is this headline and the article trying to say..? "40% of horse-drawn carriage cargo is hay, but 50% of what we feed horses is hay". So what?
From the fucking article: Fossil fuel cargoes travel long distances in very large flows, so their decline removes more than a proportional share of cargo mass. It removes a larger share of the ocean work and the fuel burned to do that work. And if I can get on my soapbox. This same problem (carrying fuel to feed the transportation unit) is well studied in medieval England because it was one of the main determinants o…
Sure, but as long as ratio of fuel moved:fuel used is good enough, people won't care (as demonstrated by historical data). This isn't an argument that leads to change. For those not already convinced of the climate crisis, you'll need to lean on economics.
Earlier quoted context omitted.
https://acoup.blog/2022/07/15/collections-logistics-how-did-... The Tyranny of the Wagon
Are you making a reference to the Tyranny of the Rocket Equation? The Earth's gravity is so large that it's almost at the limit of chemical rockets. A typical rocket is 90% propellant by mass, 8% structure and 2% payload.
Meanwhile lighter planets might have trouble holding onto atmospheres.
What the hell is this headline and the article trying to say..? "40% of horse-drawn carriage cargo is hay, but 50% of what we feed horses is hay". So what?
From the fucking article: Fossil fuel cargoes travel long distances in very large flows, so their decline removes more than a proportional share of cargo mass. It removes a larger share of the ocean work and the fuel burned to do that work. And if I can get on my soapbox. This same problem (carrying fuel to feed the transportation unit) is well studied in medieval England because it was one of the main determinants o…
Maritime shipping is very efficient, and consists of a very small fraction of overall petroleum usage.
Road transportation uses about 20x as much fuel as ocean shipping, planes use about 2x as much, and trains about the same amount.
The typical rule of thumb is that about 40% of the energy in a barrel of petroleum is lost before it goes into your gas tank. And the two big factors are the energy required to do the refining and delivering the fuel from the refinery to the gas station. Shipping the crude from the oil field to the refinery is a factor, but a small one in comparison.
This 40% is the main reason why driving an EV emits less carbon than driving an equivalently sized gas vehicle even if you're topping up that EV with the dirtiest electricity you can find.
P.S. maritime shipping typically uses very dirty fuel. We'll probably notice the reduction in sulfur pollution more than the reduction in CO2.
P.P.S 3% of a very large number is still itself a large number, so it's still worth looking for solutions.
To summarize: 40% of tonnage but 50% of tonnage-kilometres. I thought freight volume would be measured in ton-kilometres in the first place.
> This is the part that fuel-first narratives tend to miss. In a serious energy transition, coal demand falls, oil demand falls, and gas demand falls. That means fewer bulk carriers and tankers moving fossil energy around the world. The maritime sector does not have to find a one-for-one replacement fuel for all of that work, because a material share of the work should disappear.
I would argue that chipping away at all three sides of the equation reducing the amount of fuel used, the amount of fuel used for transport and transporting things using other that fuel are worth pursuing.
Earlier quoted context omitted.
From the fucking article: Fossil fuel cargoes travel long distances in very large flows, so their decline removes more than a proportional share of cargo mass. It removes a larger share of the ocean work and the fuel burned to do that work. And if I can get on my soapbox. This same problem (carrying fuel to feed the transportation unit) is well studied in medieval England because it was one of the main determinants o…
> It removes a larger share of the ocean work and the fuel burned to do that work. Sure, but as long as ratio of fuel moved:fuel used is good enough, people won't care (as demonstrated by historical data). This isn't an argument that leads to change. For those not already convinced of the climate crisis, you'll need to lean on economics.
Earlier quoted context omitted.
> It removes a larger share of the ocean work and the fuel burned to do that work. Sure, but as long as ratio of fuel moved:fuel used is good enough, people won't care (as demonstrated by historical data). This isn't an argument that leads to change. For those not already convinced of the climate crisis, you'll need to lean on economics.
That is orthogonal to the point. Shipping is considered a hard industry to reduce CO2 emissions, like aviation, but unlike aviation, 50% of the distance ships are traveling are just delivering fuel. So solving non-shipping fuel use solves nearly half of shipping fuel use. The remaining uses of shipping are also much more tractable to electrify.
Point of use generation is disruptive to many industries… not just petroleum but automotive, trucking, various services that serve both, etc. There’s a significant portion of the population employed by schlepping oil around and doing things with it to support those activities.