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Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

cleantechnica.com

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Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#41

Post by jjk166 »

lukevp wrote: post #31
bryanlarsen wrote: post #27

The top graph makes it seem much more dramatic than it is. 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. An…

Why is the EV better? Because electricity transmission is more efficient than gas? What about the losses in the electricity transmission and the batteries and the conversion to motive force in the motor? Is it way less than that 40%? And wouldn’t there be more than 0% losses because refinery -> power plant shipping? I’m pro EV by the way, I just want to understand your point better. Being able to go all the way to tr…

Transmission losses are orders of magnitude lower than transportation energy costs. You both get dramatically less loss per kilometer, and you have way fewer kilometers to travel. Transmission does get less efficient over longer distances; if you had a 20000km long transmission line it would be less efficient than shipping fossil fuels, but you simply don't need to do that.

You have conversion losses to generate motion but these are again substantially less than the conversion of chemical energy to motion that occurs inside a combustion engine. Powerplants+electric motors will have conversion efficiencies around 30%; internal combustion engines will have conversion efficiencies around 10%.

With the exception of some remote locations or emergency situations with backup generators, you are almost certainly not consuming a fuel that requires refining to generate electricity. If you're burning coal or gas, it's coming from much closer, and it's being transported in bulk to the powerplant. Trucks taking fuels to the local distribution centers and ultimately gas stations are by far the largest transportation energy expense for petrol.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#42

Post by Alpha3031 »

lukevp wrote: post #31
bryanlarsen wrote: post #27

The top graph makes it seem much more dramatic than it is. 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. An…

Why is the EV better? Because electricity transmission is more efficient than gas? What about the losses in the electricity transmission and the batteries and the conversion to motive force in the motor? Is it way less than that 40%? And wouldn’t there be more than 0% losses because refinery -> power plant shipping? I’m pro EV by the way, I just want to understand your point better. Being able to go all the way to tr…

It's a bit hard to answer the "dirtiest fuel you can find" case specifically, because there are a number of areas where EVs are more efficient. The biggest difference is probably the fact that the internal combustion engine in a car is about 25% efficient, though it depends on the RPM it is running at etc (the reason hybrids can push it up to ~40-ish% depending on how new they are is because the engine is always running at the most efficient RPM when it runs), but the "dirtiest power" specifically would probably be a coal plant which is only about 30% to 40% efficient (9000 to 11000 BTU/kWh in imperial units) due to low temperatures and the inability to run it as a 2-stage, combined-cycle sort of setup (modern combined-cycle gas turbines are ~60% efficient which is one contributing factor to gas-based electricity being cheaper even though gas costs more per GJ, though since the price of natural gas is quite volatile that sometimes changes). Of course the transportation is different depending on which fuel is used for a power plant.

In the worst-case scenario, accounting for the ~90% efficiency of the electric motors... Well, Xunmin et al. (2005) estimates 3–36%, so lifecycle emissions could be reduced by as little as 3% if you power it 100% by coal, which would be less than the what you'd get from a hybrid, but... You're not really going to find a power grid that is powered 100% by coal these days, even in China. Really the biggest advantage of a BEV, and any other electrification, is that if there are future investments in the grid (and there will be since generators don't last forever) you don't have to replace the engine of your car for it to automatically reduce emissions. The efficiency gains are just a cherry on top.

[Xunmin]: https://www.sciencedirect.com/science/article/abs/pii/S17505...

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#43

Post by epistasis »

Oh wow, that's far higher than I've been using in my estimates, I'd been rounding down to 1/3.

The massive reduction in oil supply from the sudden and unexpected closure of the Strait of Hormuz, with gas prices jumping but minimal economic contraction, has been great evidence that we could perform a global energy interchange far faster than anybody ever expected without causing massive damage.

However, the pushback I've been hearing a lot is that ocean freight still needs fossil fuels, that's always going to be a blocker.

In reality, it's only ~1% of emissions, and half of it goes away when we stop other uses, so solving that 0.5% of fossil fuel use, or even still emitting it, is really a rounding error. (And methanol or ammonia as well as other synthetic fuels based off hydrogen production have a great chance of stepping into that, especially as we massively scale ammonia production from electrolyzers, which also solves the fertilizer that has been caused by closing the Strait of Hormuz).

Fossil fuel based economies are inherently fragile and bound to massive price increase cycles. Changing our economies to be powered by renewables and storage will be far more stable, cheaper, and bring a massive increase in economic output. We can't switch fast enough.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#44

Post by titzer »

tsss wrote: post #33
bruce511 wrote: post #32

Earlier quoted context omitted.

In an EV about 90% of the energy used is converted into motion. About 10% goes to heat. [1][3] In an ICE engine about 30% of the energy becomes motion. About 70% is heat.[2] In other words electric motors are about 3 times more efficient than ICE. [1] an interesting side effect of this is that in cold climates you can't just harvest waste heat to heat the cabin (or batteries. ) So you end up using some battery energy…

Who cares about motor efficiency when you can only take 10% as much fuel. At the end of the day, cost is the only metric that matters.

> cost is the only metric that matters.

Negative externalities like pollution and climate change are not even priced in. Even if they were priced in, there are non-monetary factors that we could consider once in a while, but the conversation tends back to dollars.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#45

Post by HPsquared »

bruce511 wrote: post #36
tsss wrote: post #33

Earlier quoted context omitted.

Who cares about motor efficiency when you can only take 10% as much fuel. At the end of the day, cost is the only metric that matters.

The cost of EV energy (to the driver) is about half that of the cost of gas energy. And that's if you buy electricity at charging stations [1]. If you charge at home it gets less. If you have solar at home it approaches zero. Yes, the cost of the car itself is a factor, but even there prices are dropping all the time. >> when you can only take 10% as much fuel effeciency makes all the difference when we discuss % of…

Indeed, solar panels and EVs are the way of the self-sufficient rugged individualist. It's an amazing PR and marketing coup to make it the other way around and presented as something for "liberal weaklings" etc.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#46

Post by margalabargala »

tsss wrote: post #33
bruce511 wrote: post #32

Earlier quoted context omitted.

In an EV about 90% of the energy used is converted into motion. About 10% goes to heat. [1][3] In an ICE engine about 30% of the energy becomes motion. About 70% is heat.[2] In other words electric motors are about 3 times more efficient than ICE. [1] an interesting side effect of this is that in cold climates you can't just harvest waste heat to heat the cabin (or batteries. ) So you end up using some battery energy…

Who cares about motor efficiency when you can only take 10% as much fuel. At the end of the day, cost is the only metric that matters.

The commenters above, is the answer to your question. Based on their discussion, there are metrics besides cost that matter to them.

Not everyone is you.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#47

Post by idontwantthis »

jfengel wrote: post #20
bryanlarsen wrote: post #18

Earlier quoted context omitted.

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.

FTA: "We may call this problem the ‘tyranny of the wagon equation’ as a number of readers have noticed the similarity to the tyranny of the rocket equation."

God’s work.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#48

Post by margalabargala »

braiamp wrote: post #28
mynegation wrote: post #19

To summarize: 40% of tonnage but 50% of tonnage-kilometres. I thought freight volume would be measured in ton-kilometres in the first place.

To further give context: the article is saying that most of the fuel transported around is done for long distances, so when something removes fuel use in the consumer side it has a double dip effect: less fuel consumed and less fuel used to transport the fuel, since long fuel supplies route diminish. It's a third order of thinking and that's why it's confusing. The article then argues that reducing that consumption i…

I wonder if this actually has the potential to have the opposite effect.

If an oil producer electrifies faster than average, for example Norway, then oil that might have been consumed domestically instead is shipped overseas.

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#49

Post by [deleted] »

lukevp wrote: post #31
bryanlarsen wrote: post #27

The top graph makes it seem much more dramatic than it is. 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. An…

Why is the EV better? Because electricity transmission is more efficient than gas? What about the losses in the electricity transmission and the batteries and the conversion to motive force in the motor? Is it way less than that 40%? And wouldn’t there be more than 0% losses because refinery -> power plant shipping? I’m pro EV by the way, I just want to understand your point better. Being able to go all the way to tr…

[deleted]

Re: Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

#50

Post by AnotherGoodName »

jjk166 wrote: post #41
lukevp wrote: post #31

Earlier quoted context omitted.

Why is the EV better? Because electricity transmission is more efficient than gas? What about the losses in the electricity transmission and the batteries and the conversion to motive force in the motor? Is it way less than that 40%? And wouldn’t there be more than 0% losses because refinery -> power plant shipping? I’m pro EV by the way, I just want to understand your point better. Being able to go all the way to tr…

Transmission losses are orders of magnitude lower than transportation energy costs. You both get dramatically less loss per kilometer, and you have way fewer kilometers to travel. Transmission does get less efficient over longer distances; if you had a 20000km long transmission line it would be less efficient than shipping fossil fuels, but you simply don't need to do that. You have conversion losses to generate moti…

The other nice thing is that the batteries on cars can effectively act as grid energy storage even without v2g. Simple offpeak/low rate charging setups can take the most efficiently generated cheap power.

In Australia power prices are often negative in the day due to solar and there's various variable rate plans you can get to take advantage (Australia dwarfs all other nations in per capita solar; even China is nowhere close per capita). I know workplaces that will actively encourage you to charge your car at work.

Power prices due to the excess solar keep falling - eg. 10% fall nationwide in July (middle of winter in Aus so not even near peak solar). https://www.theguardian.com/australia-news/2026/may/26/power...

For all the talk of 'solar can't replace fossil fuels' or 'electricity isn't green' Australia's gone and created a nation wide energy market that encourages rooftop solar and it's found itself with excess daytime energy at a time when the world has an energy crisis in Iran and the datacenters going up everywhere.

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