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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. 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.

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> We'll probably notice the reduction in sulfur pollution more than the reduction in CO2.

I feel like I've read something about the effects of reducing sulfur production already: https://www.climate.gov/news-features/feed/unintended-warmin...


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 transportation using clean energy is an obvious benefit of EVs. The “dirty electricity” angle is less obvious to me.


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 if you need heat.

[2] ICE motors vary in effeciency a lot. 20-30% is typical. The Carnot formula comes into play here.

[3] because there is so little heat generated, the cooling systems (EVs still have them) are much smaller. And simpler (for example, no fan, 'cause there's no heat when standing still.)


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 fuel. 90% of 100 mj is the same as 30% of 300 mj. So already the "fuel" can be 66% less. Generally though the raw amount of mj isn't a very important number. A better measure (which takes effeciency, and tank size into account) is "range". But even that is somewhat meaningless. At some point range is "enough". For daily commutes that may be 50 miles. For long-distance it might be 500 miles.

In only a very few cases would a pickup with 2000 mile range be more useful than one with 1000 mile range.

Plus you can also factor in maintenance costs. The cost of ownership of an ev, from a service and maintenance point of view is a lot lower.

[1] ymmv somewhat. Although electricity prices vary a lot, so do gas prices. The 50% saving (at worst) is a pretty good rule of thumb though.


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.

Right, the set of people who actually pump their own oil out of the ground, refine it into something you can put in a modern vehicle engine and drive around on that is likely zero, but the set of people who own panels and storage so they can fill their EV includes my team lead, who is just some guy on a pretty average salary living on a modern housing estate.

The bio-fuel people at least make some kind of sense compared to fossil fuel "survivalists" - but again they're portrayed as just tree huggers!


I think 1600 watts of solar panels produces enough energy to drive an EV 12000 miles a year. Your car though would have to be always plugged in during the day. But probably 3200 watts would be enough for a car used for commuting to be charged mornings, evenings, and weekends.

> Your car though would have to be always plugged in during the day

Or just have a second stationary battery to store up the energy while you're away during the day.


>It's an amazing PR and marketing coup to make it the other way around and presented as something for "liberal weaklings" etc.

If there is such a marketing, then people relate to it because EVs are not suited for handling unpredictable situation. You got stuck in a ditch in the middle of nowhere at night, you loss all of your battery getting out of it, and now you are stuck. So you can't take it to unforgiving places.

EVs are great for boring commute that is it. I don't see it changing any time soon.


> You got stuck in a ditch in the middle of nowhere at night, you loss all of your battery getting out of it, and now you are stuck.

I find it interesting how you’re presenting that incredibly unlikely scenario as a serious objection to an EV when simply going off the road is a once in a lifetime or less situation for most drivers, much less precisely calibrating it so your vehicle is not damaged too much to be unusable but still needed a massive amount of power to get free.

That’s an interesting counterpoint to something which happens to thousands drivers every year: having a bad storm cause them to sit in lengthy lines waiting for fuel (this was weeks the last time I was in Florida) or, in colder weather, idling through a tank of gas while stuck waiting for ice to be cleared.


The EV also has a ton more torque to get out of the ditch, and can apply it at very low speeds.

If you slide off the road and get stuck in a ditch in the middle of the night, an EV is a lot more comfortable. Standard advice for keeping warm is to run the engine for ten minutes every hour and keep the window cracked open due to risk of carbon monoxide poisoning. By contrast, you can leave the EV with the heat on all night.

You have used multiple gallons of gas getting "unstuck" from somewhere? That is a ridiculous scenario.

Surely you call a recovery truck to come pull you out and do an emergency charge on your battery, similar to how they’d provide you with emergency gas if your tank ran dry? Or tow you if they don’t have a charger?

If you run out of gas you’re also stuck. Only upside is that the recovery service can bring you a few gallons of fuel instead of a tow.

I somewhat suspect that's a temporary state of affairs. Nothing prevents a couple tons of batteries being put on a truck with a CCS charger to achieve the same thing.

It won't be efficient but neither is driving a few liters of fuel to someone from a gas station.


Tow trucks are sometimes needed for gasoline cars too.

Before the Iran war, I did a back of the envelope calculation for the price of gas of your average ICE for a certain fixed range vs. the price of electricity an average EV uses for the same range. This was under the assumption that you buy electricity at a random charging station that you don't have a contract with.

Based on these average values I used, EVs fared slightly worse.

This was not factoring in costs of purchase or repairs etc. And all averages were taken off the internet so everything had to be taken with more than a grain of salt. But the outcome was nowhere near your statement of EV energy costing about half of the cost of gas for the driver.


I've only had an EV 3 months now, but it'll never see a charging station.

I pay around $.12/kw and get 4 miles per kw. So my "energy" costs are $.03/mile. I have a Mazda cx50 as well, it gets about 20-22mpg, with the gas prices here in Seattle that's around $.30/mile. Even where gas is cheaper that's still $.20/mile. Literally 10x the cost to run a gas car vs an EV.

I'm honestly shocked at how many people have EVs and rely on charging stations. I mean, I think it's a low number, but the fact that it's more than zero is shocking to me.


More people own cars than houses. I live in an apartment, and the only ways I'd be able to charge an electric car are expensive charging stations or plugging in an extension cord, leaving a sliding door cracked all night and hoping the property's management doesn't throw a fit, pets don't sneak out, somebody doesn't break in, etc.

I've got a hybrid now, at least.


There’s plenty of cheap charging to be had in parking lots you’d otherwise park in. Many employers have charging stations. Plenty of apartments offer charging.

But even if you can’t find any of those, L2 charging at stations is half as expensive as fast charging.


The pacific northwest’s vast hydro capacity makes it maximally attractive to own an EV. The rest of the country isn’t nearly so lucky.

Neither Oregon nor Washington are in the top 10 states for cheapest residential power. Everywhere except for the Northeast and California has prices within a few cents per kWh of the Pacific Northwest.

Doesn't make electricity much cheaper

One of the reasons Norway can go all electric (EV’s), but most of the world doesn’t have the hydroelectric resources they have.

Maybe it’s not as much cheaper but it’s cheaper than gas anywhere in the country.

I’m at $0.11 in Maryland which gets 40% of its power from nuclear.

I'm in the EU and the factor is 3-4x.

> buy electricity at a random charging station

Well there's your problem. Try doing the same calculation with the average residential electricity cost. Most car use is for commutes after all, so most people can just charge their EV in their driveway every night.

Destination charging and rapid charging are notoriously expensive. It's a luxury product intended for a once-a-year road trip. It is not even remotely representative of your average charging cost. Street-side charging is slightly less excessive, but you're still paying a serious premium.


> so most people can just charge their EV in their driveway every night.

That does presume that those "most people" have a driveway where they can do charging. I.e., all apartment dwellers with cars in parking lots/garages (excluding those few that may have installed electrical plugs at each parking spot) are cut off, as are city dwellers without driveways who park on the street (or in another garage, again without electric hookups for charging).

Yes, eventually those garages and parking lots will likely include some form of "car charging" infrastructure, but until that happens, "most" is not as big of a percentage as that word makes it appear.


It's probably too much to say everybody can do this, but a lot more can than seem to be included in typical estimates. Tomorrow I will walk to work and probably (if the owner hasn't left by then) I'll pass an EV that's plugged in to presumably an ordinary mains supply... via a hole cut in their fence because their car is sat on the street. I'm sure that sometimes they find somebody else took their prime parking spot, but not often. And of course "run the cable through the hole in my fence and lay down the conduit to protect it" isn't exactly an ideal setup, but it works and the car doesn't care how the electricity got there.

In the city you just take the bus or metro. Did that for 22 years, no issues.

We just bought our first (used) EV, and charging stations are the Wild West right now. Any random station you pull up to might charge close to the local cost of electricity, or some wild sky-high amount. And hopefully they’ll tell you what that is before you have to swipe your card. There the economics can swing towards gas cars depending on how absurd your local charging station prices are. For people filling their tank every couple days because of a 2 hour commute or something an EV may still not make sense financially. But if you’re putting in under 40 miles and have even a modest 120v 12 amp circuit you can plug into at home (e.g. a dedicated washing machine circuit) you’ll likely only need a charging station on rare occasions such as a road trip. As a matter of fact I am writing this from our first EV road trip. The inconvenience has been comparatively minor and our “fuel” costs should end up being about half of what they would have been in our hybrid SUV.

The Toyota Prius and the Rav hybrids are popular for many of the reasons you mentioned.

Doing the equation regularly would be interesting.

There are some other parameters to consider too. Stopping for fuel is not something I enjoyed. I can charge at home. You won’t have to stop to refuel in an EV unless you’re going a long way. If you’re going a long way the stop will be longer. Much worse.

You won’t service an EV much, that’s nice.

The silence is bliss.


Were you using DC fast charging stations or level 2? Fast charging is about 2x the price.

If you think about it as "buying fuel" rather than as just a routine part of owning the vehicle I think the "fast charging" seems like how you'd do it. Like how at the turn of the century people bought a mobile telephone to make telephone calls. What do mean it's a computer? Why would you want a handheld computer?

Humans are like this about a lot of things, imagine what it was like before widespread universal literacy. Why are we teaching everybody to read? What are they going to do with that skill? Until you've tried it, the fact that your entire populace can read doesn't seem like it would make a big difference.


In my area the fuel cost of a hybrid car is a better deal than recharging an EV at PG&E retail rates, but this is just a policy knob that we can turn whenever we decide to get serious about reducing greenhouse gas emissions. If people are ambivalent about the operating costs of EVs then it is up to the government to put their thumb on the scale with a motor fuel tax, such that EVs look like a great bargain.

Before I drove an EV, I drove a 50 mpg Prius. At California prices of ~$4/gallon, that’s $.08/mile.

My post wildfires NEM2 off peak rate for electricity is $.40/kWh. My Bolt gets 4.5 miles/kWh. That’s $.1125/mile.

If I were driving a Tesla it would be worse (my wife’s Tesla lies mercilessly about its range when full; it’s like Elon Musk recapitulates himself; real world it gets about 3.5 miles/kWh), and if I drove a Rivian it would be MUCH worse.

So, in California, it isn’t true at all (mostly because rate payers are funding PG&E’s liability) that the most efficient EVs are cheaper than a good mileage gas car. No where near a 2x advantage (it was better, but not nearly 50%, when I bought it, more like 90% of the gas cost). At no point has it ever been close to 50% cheaper for fuel in California (which, as it happens, sells by far the most EVs).

Generally speaking, I think EV proponents (like me!) should spend a lot less time promoting “it’s cheaper”. It is, in practice, cheaper, because maintenance is cheaper. But Americans don’t care about levelized costs, they care about the highest salience variable expenses, and trying to convince them to do otherwise is a losing argument.


My xpeng g9 goes about 570km in summer. Less in winter, like 480 maybe. Longest range ICE i had was a mercedes wagon that went 1050km on one tank of gas.

Filling the wagon today would cost me like 170 euro. Filling my xpeng happens overnight and is about 7-9 euro depending on grid pricing.


> 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.


Many countries have high fuel taxes that approximate pricing in the negative externalities.

Assuming you think price as a signal is the solution to dealing with those externalities, it doesn't matter what caused the price to be high.


Fuel taxes are "in theory" the mechanism to price these in, but today, they are not, and how this money eventually has the opposite effect! Revenue from fuel taxes is usually funneled to more transportation infrastructure (> 80% to road construction in the US, only 15% to mass transit). The vast (and ironic!) indirect effect is more cars, more car miles, and more consumption--a long-term, indirect subsidy to fuel and auto industries. Approximately zero goes to regulation enforcement (like emissions inspections and other enforcement), which is funded by usage fees and general income taxes.

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.


Very, very few people actually need to drive 500 miles in a day. Tank size is about convenience, about how often you need to go get gas and what times of day the stations are open.

You can recharge your car at home every night. At 2 in the morning.


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.


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.


I don't disagree with you but every country is different. Australia gets a lot of sunshine and is sparsely populated, so plenty of room for solar anyway. This is not the case everywhere though.

It can be a good example though of how you overproduce during the day and use that to charge car batteries for example


Australia is at about 3,5 persons per square kilometre and as you say one of the most sparsely populated countries on earth.

Compare to for example Denmark at 149 persons per square kilometre. Denmark needs about 35 TWh per year in electricity, so about 1,7% of their land area would need to to covered with panels to supply that.

(This is obviously napkin math and just a thought exercise)

If they were to convert their sheep pastures to dual-use like this (https://www.americangrassfed.org/solar-grazing-with-sheep-a-...) Denmark would be almost 40% solar powered without giving up any additional land area.

Denmark obviously has a lot of wind power and should not convert to a majority solar power for their grid, but I want to illustrate that the land area use may not necessarily be such a strong argument against significantly increasing solar power in more densely populated countries.


So why is Denmark along with the Swiss currently working on Thorum?

>> The “dirty electricity” angle is less obvious to me.

A power plant typically gets about 60% of energy from a fossil source. A car does about 30%. So even if the electricity comes from say coal, it's still more efficient than buying gas in a car engine.

Of course, these days, it's likely that a substantial portion (up to 100% in some cases) is not "fossil electricity" but rather comes from solar, wind, hydro etc. Ie "clean" electricity.


60% efficiency? How do these power plants manage to circumvent the limit set by Carnot efficiency?

Natural gas burns at ~2200 K. Ambient temperature is ~300 K. 1 - 300/2200 = 86% as the Carnot limit?

They don’t. they capture the waste heat from the gas turbine and use it to make steam to spin another turbine. A gas turbine is ~40% efficient, add in a HRSG to make a combined cycle plant and you can get up to ~60%. You don’t even need a gas turbine to use a HRSG, any exhaust stream with enough heat will work, a boiler plant or similar.

https://en.wikipedia.org/wiki/Heat_recovery_steam_generator

https://en.wikipedia.org/wiki/Combined-cycle_power_plant


Coal burns dirtier and and is more Co2 intense than gas though.

Our energy aggregator is a non-profit Community Choice Aggregator with over 250,000 members that ensures 50% of the energy they purchase comes from renewables and 75% of all energy purchased is carbon free. And for an extra $0.00750 p/kWh you can opt into your consumption coming 100% from renewable sources.

Highly recommend everyone watch this video https://www.youtube.com/watch?v=KtQ9nt2ZeGM

Briefly, the most important reason an EV is better because it unlocks energy portability. You gain the flexibility to source your energy in many more ways than with a gas car. Oil energy is about as optimized as it's ever going to get. With electricity, we're just getting started.


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. "dirtiest power" - coal is dirtiest at the site of consumption, but if you consider the entire supply chain, diesel generators at remote locations might be worse. (Coal is usually supplied directly by train; diesel has to be refined and shipped in by truck.)

As I understand it, it's a mix of factors.

Charging Lithium, and converting to motive force in motors are both pretty efficient. (Both >90%).

An ICE vehicle has an upper limit on efficiency that is lower than what a modern fossil fuel plant can reach, and the ICE is less likely to sit at peak efficiency all the time. The world record, set this year was 48%. Previously, it was 41%.

Power plants are much more likely to be kept at or near their peak efficiency and have the space for systems like heat recovery (to recapture waste heat) and emissions controls. For a gas turbine plant, I think the record is ~64% sustained.


Grid loss is maybe 5%.

The important driving factor is that generation becomes more efficient when you can use natural gas to turn turbines directly and then capture the waste heat to boil water and turn turbines with steam. This is called combined cycle if you want to google it to learn more.

Another thought exercise, if generating electricity with fossil fuels wasn’t more efficient at scale, why would we bother building a grid in the first place? Every house would just have a gas generator.


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

It's all projections, too. They don't even have a line to show where they are going from actuals to guesses.


Does "the future is a prediction" actually have to be explicitly stated?

Yes. It's important to know whose prediction, and what it's based on.

">15% of corporate revenue is expected to come from the metaverse in the next 5 years according to 25% of senior executives" - McKinsey [1]

[1] https://www.mckinsey.com/capabilities/growth-marketing-and-s...


> Road transportation uses about 20x as much fuel as ocean shipping, planes use about 2x as much, and trains about the same amount.

I’m misunderstanding something. Planes use twice as much fuel while road uses 20x more?


There are way more cars than planes.

Oh, is this a fleet measure rather than a 'per unit moved'?

Yes, all road transport together uses 20x as much fuel as all marine transport together.

> trains about the same amount

The nice thing about trains is that they can run on electricity.

It does require investing in overhead wires.


They aren’t great at shipping things from Europe and Asia to the United States, though.

Wouldn’t water have a lot more drag than wheels?

Yes but it's also buoyant. You can put a lot more stuff on ships, and increased inertia does offset the drag losses versus acceleration losses

I suspect that the GP's numbers are total, not per ton-mile of cargo (which, to my mind, makes them useless for efficiency discussions). They might make sense for discussion of the actual article, though.



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