So when you look at the headline "efficiency" of an electric car, you need to take that thermodynamic penalty into account first.
A modern series hybrid like a Toyota Prius is effectively an electric vehicle and a gas generator (which means it has the same efficiency gains due to regenerative braking). That gets 52 mpg, which is about 493 Wh/km. If you generated the 225 Wh the Tesla needs in even the most efficient combined cycle gas turbine powerplant you'd need 375 Wh. Less - but not nearly as drastic as it first seems.
Renewables change the picture though - once you have significant renewable generation the carbon intensity of electricity starts dropping, which means that remote powerplant vs local powerplant argument falls apart. That is when the real power of electric vehicles kicks in - they can take their energy from anywhere.
Yes it usually is
I fell down a rabbit hole and found this link, which gives 46% for the theoretical limit for the efficiency of the internal combustion engine.
https://physics.stackexchange.com/questions/98966/maximum-th...
[1]: https://engineerine.com/meet-wartsila-31-worlds-most-efficie...
I don’t get your point on centralization however - more efficient but less robust (just like in software).
Wait, does a new prius or something like a hyundai ioniq (also 52-53 mpg) not have the internal combustion engine mechanically coupled to the transmission and drive wheels anymore?
I really like this setup, because it gives economy, but also a range and I don't need to worry about where to charge the car.
I also take issue with anyone calling a hybrid 'effectively an electric vehicle.' That is only true for PHEVs. A regular hybrid still gets exactly 100% of it's energy from gasoline.
While ICE are heat engines with a theoretical limit of 70%, they’re more specialised subsets described by the Otto (gas) and Diesel (… diesel) cycles, which have a much lower theoretical maximum.
Just plugging the temperature ranges into Carnot will give you a Carnot limit of 50%, and using Otto will yield 46% (https://physics.stackexchange.com/a/98992).
Add in that gas engines are not spherical and into a vacuum (losses and delays) and you’re in the 30s.
Once you get to cruising speed the transmission usually engages something called a "lockup" that bypass all that to get as close to the 100% number for energy transfer as possible.
Anything that doesn't require charging directly from the grid all the time, because although parts of the USA and Norway are ready for that, it's very tricky to get right globally.
Maybe hybrids like the Prius get to be so efficient that such cars will have a truly negligible impact on global warming.
Imagine you were tight on money and then think about your grocery store bill. Wouldn't you try to save in all categories, even though, say meat, was "only" 11.9% of your total bill?
Carbon reductions need to be made in every sector.
I looked at the link and to me transportation does indeed seem one of the larger sources of emissions. Everything else seems either very fragmented (lots of entries with around 2%) or similarly if not more complex - like energy use in buildings for all of the appliances.
What am I missing here, what would be easier to address than the abundance and types of cars and possibly the lack of proper public transportation?
I don't think that one can even make the argument that we should look for easy wins when change is necessary everywhere, unless we want climate catastrophe - because of people working against improvements due to their personal interests, inefficiencies in regulation and enforcement, as well as any number of other factors.
You can use a smaller battery, which means using less rare materials that are very expensive. There are a lot of indirect emissions with electric vehicles, and it's important to look at the big picture.
It's an argument pushed by fossil fuel company's because it pretends the world is static and unchanging, as though the energy mix of the electrical grid can't vary, or that changes in fuel source and process for mining operations to be cleaner wouldn't drastically effect downstream users overall emissions profile.
CO₂ -> C + O₂
2 H₂O -> 2 H₂ + O₂
C + 2 H₂ -> CH₄ (methane)
[1] https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_proces...
You're just going to throw that out there? You'll cite the Fischer-Tropsch process, but not "actually global temperatures are declining"?
Here[1]. The temperature hasn't gone down. The narrative hasn't changed from global warming because of this (the term was in fact dropped because people are idiots and trying to explain what global temperature is measuring in terms of energy dynamics in the climate system doesn't work...). 2022 was the 6th warmest year on record, and based on all data the overall trend is up.
[1] https://www.noaa.gov/news/2022-was-worlds-6th-warmest-year-o...
May I suggest a less belligerent/dogmatic attitude when discussing this subject? If the narrative holds it won't change the conclusion. If new data shows the narrative to be false or misleading - e.g. ice core records show the atmospheric CO₂ concentration to lag behind temperature changes, not lead them, climate sensitivity wrt. CO₂ concentration is low, feedback mechanisms are unclear, there are far too many fudge factors in the climate models to make them reliable sources - it will be much easier to adapt to the new situation. We're not talking religious dogma after all but scientific theory, that which can and should be discussed lest it turns into the former.
[1] https://www.washingtonpost.com/news/capital-weather-gang/wp/...
[2] https://www.climate.gov/news-features/climate-qa/why-did-ear...
[3] https://climate.nasa.gov/global-warming-vs-climate-change/
Running the denialist playbook as usual: slip in a insinuation that the issue has stopped without evidence, then drop a bunch of articles which don't support it while continuing to say "what if all the data supported me?" And then started alluding to a conspiracy with language choices like "dogma". Throw in some upfront tone policing because heaven forbid you have to defend your position vigorously and the recipe is complete.
Go on: hit me with "climate cycles are natural" and then lean into how the media just don't talk about the controversy.
Please refrain from using terms like denialist, it does nothing to help the discourse. Also, that 'bunch of articles' I sent does support what I said, this being a break in the rising temperature trend. You seem to want to hear much more in what was said, why is that?
As to the 'conspiracy with language choices' I think you realise that this is no conspiracy but a simple fact - what used to be called 'global warming' is now called 'climate change'.
As to 'tone policing' I'd suggest reading your posts I replied to.
[1] https://en.wikipedia.org/wiki/Holocene#/media/File:Holocene_...
When one party wins by default, they benefit from stalemate-seeking tactics. "Just Asking Questions" unfortunately works very well for this purpose. Dogma poisons the discourse, yes, but so does accidentally extending good faith to a bottomless well of bad faith questions, which has been the conservative playbook on climate change since forever. I learned this the hard way, over and over again. The counter-strategy is dogma.
In order to have a scientific discussion rather than a political discussion, we need to know your intentions, and that's extremely difficult on a pseudoanonymous internet forum. It sucks, but this is probably how it has to be.
The truth, freed from ideology. This will be hard to achieve given the enormous amounts of money involved on all sides - from "green new deals" via trillions of € in subsidies to even larger amounts of money on the fossil-fuel-status-quo side. With politicians who have made their careers on either portraying themselves as apostles of Gaia or ensuring the continuous flow of oil, gas and coal - and thus the continuation of an industry which more or less defined whole US states and several countries.
Just because it is hard - and probably impossible - to get the actual truth does not mean I want or need to cave and just follow one of the narratives. Given enough people looking for the actual truth it may become possible to reach it and act upon it but it better be sooner rather than later.
What is your purpose in asking such leading questions by the way? Do you agree that an actual scientific discussion - as opposed to one directed by The Science™ - is the better course? Also, who are the we who would like to know? I speak for myself, not for others. Who do you speak for?
The IPCC reports are one google away.
When you're done reading at least the abstracts in the IPCC reports - but it is worth the time to read the actual reports themselves - you can also read a few other sources, e.g. Schellenberger's Apocalypse Never: Why Environmental Alarmism Hurts Us All, Björn Lomborg's False Alarm: How Climate Change Panic Costs Us Trillions, Hurts the Poor, and Fails to Fix the Planet and Steve Koonin's Unsettled: What Climate Science Tells Us, What It Doesn't, and Why It Matters. These give a far better view over what climate change entails and how it can be dealt with than the breathless fear-mongering as seen in the media and as spouted by politicians.
It's a much longer trend than 2012-2016. I remember 2011, the last time conservatives were playing the "global warming has paused" game, but then oops! It returned to trend. No Ls were acknowledged, of course.
What do the radiative flux measurements say this time around? They measure the derivative directly and are upstream of the most chaotic mixing process. Last time they said "sorry, heat is still piling up, globe's still warming." They were correct. What do they say this time?
2012-2016 is not the period of warming, it is the period from which the warming trend changed into a cooling trend. Seen over the last century the warming trend is far longer, the most recent one starting somewhere in the beginning of the 70's until the mentioned 2012-2016 frame. After that a slight cooling period followed, taking down the temperature by 0.06°C/yr until 2022. 2022 was another warm year so if 2023 will be warm as well the cooling trend is most likely broken. These sort-time variations are not significant when discussing 'climate' - roughly defined as 'the weather trends over at least a 30 yr stretch' - but they do control what makes the news.
One question: why do you state is is ´conservatives' who claim that the warming trend was broken? You don't know whether those people were conservatives nor do I. It does not make sense - and is extremely counterproductive - to equate a person's stance on single issues like 'climate change' with their political affiliation since these issues should not in any way be connected to political ideology. If they are connected they are by definition suspect since ideology trumps objective reasoning. Either the climate changes - and it does, no question there - or it does not, independent on whether you or I vote for whatever party we choose. Allowing ideology to taint the discussion just turns off a large part of the populace no matter which ideology it happens to be. It is just plain stupid for climate change to be a 'progressive' cause, crime reduction to be a 'conservative' cause, etc. These issues should be pulled out of the ideological realm so that they can be discussed by everyone without accusations of -isms by 'either' side.
<compose> + _ + [0-9]
superscript: ^ + [0-9]
O⁰… O⁹
The long-winded way is to use your OS's character map tool: find the glyph you want there and copy+paste. Under Windows 10+ there is the emoji keyboard (hit [win]+;) which also gives access to much more including super-/sub- script characters, which is a little more convenient than character map. Presumably other OSs have similar available too.
Better is to have support for a compose key sequence. Usually build in to Linux & similar, you just might have to find the setting to turn it on and configure what your compose key is. Under Windows I use http://wincompose.info/ and there are a couple of similar tools out there. In any case it is useful for more than super- and sub-scripts: accented characters & similar (áàäæçffñ), some fractions (¼,½,¾), other symbols (°∞™®↑↓←→‽¡¿⸘♥⋘»‱), and configurable too so you can make what you use most easiest to access (and if you are really sad like me you can do something https://xkcd.com/2583/ to type hallelujah too!).
On mobile devices a fair few “special” characters are usually available (though it depends what keyboard you have installed) via long-press on the right keys of the virtual keyboard.
The second reason is that hydrogen is 1/10th the density of diesel even when liquid (which is as dense as it gets). Maintaining hydrogen in its liquid form is energy intensive. Hydrogen tends to leak through the smallest cracks and also because the atoms are so small tends to leak even through solid metal. To sustain the high pressures and degradation by hydrogen you need a very expensive tanks. You also need to handle the case, when the car crashes/ catches fire releasing all of the hydrogen somewhat safely. This tends to be a 6 MW flame upward of the car. Too bad if it crashed under a bridge or garage. This is much worse than a burning ICE/ BEV car.
Hydrogen gas stations have all of the problems with the tanks as well. That makes them very expensive. Battery charging stations are somewhat easier - everywhere you have higher voltage you can build a decent charging station. Big parking lots can have solar roofs fulfilling a part of the charging demand and keeping the cars colder in the summer.
At the same time you don't have any of the advantages of batteries - such as that you can charge them almost everywhere or when breaking. Hydrogen cars would need to be hybrids basically to improve on these, in this regard they are more similar to classical ICE cars.
Finally, making hydrogen ecologically and economically is not that easy in big quantities. In the end, you realize it is means to a longer operation of the infrastructure of classical fossil fuel companies. Unrelated to cars, you can put some hydrogen (up to about 8% it seems) into natural gas without noticeable change in properties when used for heating. But you can probably slap a green or at least "blue" stamp on the solution. In the end, all of this is just as damaging as the production/ burning of bio diesel/ gasoline spiked with ethanol. Putting hydrogen into cars would just make support this fossil fuel agenda without actually helping the environment much and quite possibly enable decades of even more damage to the environment and public health with profits mostly for just a few already filthy rich people.
[0] https://www.quora.com/Can-I-create-a-Hydrogen-fuel-cell-with...
It is surprisingly difficult to get numbers on how much oil is used to extract, refine and transport oil.
The best I found was this:
https://www.speakev.com/threads/energy-required-to-refine-oi...
Does anyone have better numbers?
https://sustainability.equinor.com/climate-tables
The headline figure is maybe to compare 11.4 mill. tonnes CO2e emissions from "Scope 1 + Scope 2" (direct emissions from the company plus indirect emissions because they buy electricity and stuff), versus 243 mill. tonnes CO2e from Scope 3 (emissions from people burning the hydrocarbons sold).
If that figure is correct, you can add 1.6 percent to the car tailpipe emissions figures to account for production and refining etc.
But this is an oil & gas company that tries very hard and is among the best in the world for minimising emissions from production and refining. I would not be surprised if gasoline from US shale oil is more than an order of magnitude worse.
https://www.sciencedirect.com/science/article/pii/S030142151...
Whereas if you compare CO2 emissions, you can do these things and in theory get down to zero emissions from production and refining of gasoline.
Damn, I've never thought about that before. In hindsight that feels like an obvious thing to consider but this is the first time I'm aware of that thought entering my brain. Thank you for provoking the thought.
What would be the equivalent consideration on the other side? Would it be something like inquiring into the energy requirements of creating and maintaining the electrical grid, especially given the increased load of wide-scale vehicle electrification, instead of assuming we get that for free?
Anyway maintaining a more robust grid should be much cheaper than maintaining thousands of gas stations and the trucking routes used to keep them filled up.
ChatGPT summary:
In 2019, the world seaborne trade volume reached about 11.08 billion tons. Out of this, crude oil, oil products, and gas accounted for approximately 32.5% (3.6 billion tons) of the total volume. Coal made up another 8.4% (935 million tons). In total, energy products represented around 40.9% of the global seaborne trade volume.
It's important to note that these figures are from 2019, and the percentages may have changed since then due to various factors, including evolving global energy markets, fluctuations in demand, and the transition to renewable energy sources. The percentage may also vary depending on how you define "energy products."
Sources: https://unctad.org/webflyer/review-maritime-transport-2020
But yeah, no one then goes on to give equivalent numbers for petroleum.
Not to mention the socialized costs of all the wars, military spending and human lives spent to secure stable sources of fossil fuels. If you actually break down the numbers and applied some basic ethics, I doubt fossil fuels have been cost competitive for decades.
<snark, i'm totally against military aggression>
It's almost as if they want an excuse for running a massive military.
It's not like renewable energy doesn't take resources/energy to produce as well. It's just borderline impossible to get real numbers because you'd pretty much need perfect information on the supply chains.
Not saying that renewables don't still win in such a comparison.
There must be small impact of that as well to the CO2 calculations.
If your car gets 30 mpg, has a 16 gallon tank (that you refill at 1/4 tank, so you're buying 12 gallons), and you drive an extra 5 miles to pay $3.93/gallon instead of $4.00/gallon, how much did you really save?
I'll give you a hint: It's less than a nickel.
Meanwhile, you've probably driven at least 10 minutes that you didn't need to drive. 10 minutes to save a few pennies.
The math only gets worse as the gas prices go up and your fuel economy goes down. You need a greater delta to make the drive worth it.
Siting a gasoline station is highly strategic. They know exactly where to put them and how much to charge on the real estate and vendor sides.
On the way to the charging station, we probably pass a dozen gas stations.
I love my EV but let's not pretend it's always more convenient. If you have the opportunity to charge at home/work then yes it's great, but you're still reliant on public charging infrastructure if you decide to drive outside your normal range, and it takes a lot longer to charge than it takes to fill up a tank of gas, even considering the speed of Tesla Superchargers.
(1) Alberta tar sands production, which relies on imports of natural gas to melt and process the tar sand into a crude oil equivalent, called syncrude. If the syncrude is shipped to San Francisco Bay for refining at Chevron's Richmond Refinery, then you have to tag on the shipping fuel used, the gas used in the refinery, and finally the tanker fuel used to move the fuel to a gas station in San Francisco. Finding all these numbers is not easy, it's often proprietary, but you can find that a lot of natural gas is used at refineries (bulk numbers):
https://www.eia.gov/dnav/pet/pet_pnp_capfuel_dcu_nus_a.htm
(2) Sweet light crude from a pressurized reservoir that's refined a few miles away from the oil field and used in a nearby city.
The end-product, refined gasoline, has the same state property (energy density) regardless of how it was manufactured, but that's irrelevant for getting the energy that it cost to make it. I imagine the spread can be pretty wide indeed, as the above examples show.
Generation can be from clean sources and is already happening in some jurisdictions.
Even if a clean source is not available, the pollution can best be controlled at the source. In this period of history, hundreds of millions of people make billions of polluting trips every day in their communities.
Although owning any car is the poorest choice of all for the environment, there are two ecological benefits to driving a BEV or a PHEV.
* better efficiency than ICE
* zero emissions in the case of BEV, zero emissions *for most trips* in the case of PHEVYou mean thermal energy?
Both cars are converting chemical energy to kinetic. The theoretical maximum for this is 100%. But one uses a thermal intermediate step, that reduces that maximum.
How close/far would you say we are as a society on "having significant renewable generation"?
https://www.eia.gov/todayinenergy/detail.php?id=55960
They're still pretty close to each other right now. Renewables are at 21%, coal 20%, nuclear 19%. However, nuclear is flat and coal is declining. Renewables are still growing rapidly and will widen their lead significantly in a few more years. See the first embedded chart in the article, showing output trends since 2010. Also see the short term forecast at the end of the article:
"In our March Short-Term Energy Outlook, we forecast the wind share of the U.S. generation mix will increase from 11% last year to 12% this year. We forecast that the solar share will grow to 5% in 2023, up from 4% last year. The natural gas share of generation is forecast to remain unchanged from last year (39%); the coal share of generation is forecast to decline from 20% last year to 17% in 2023."
[0] https://en.m.wikipedia.org/wiki/List_of_coal-fired_power_sta...
Just to expound on this. Power stations turn fuel to heat, and heat to electricity via steam turbines.
In ICE cars, that heat is the main loss of power. Whole systems in cars are built to get rid of that excess heat in the engine.
ICEs are most efficient under medium-low RPMs and high load. The electric motors can sustain low speed cruising, letting the engine shut off entirely if it wouldn't be well utilized, and also fill in for high torque demand to keep engine power output lower.
In the United States and some other countries, a gallon is equal to 128 fluid ounces or 3.785 liters. Meanwhile, in the United Kingdom and some Commonwealth countries, a gallon is equal to 160 fluid ounces or 4.546 liters.
But wait there’s more! The US also has the “food labelling” fluid ounce which is not the customary one, instead it’s exactly 30mL.
I mean, there are a million things, that do not need universal standards, but standards are imposed anyway.
But where one standard would be really helpful, like scientific values, we have many. And some people would rather go to prison, than adopt. (I think that happened in the UK, after they force switched to metric)
1 ft = exactly 30.48 cm; One pound is exactly 0.45359237 kilograms as in 0.453592370000000000… kilograms.
At no point was it ever illegal do display the old units. There were no martyrs; there were only idiots.
(Quite normally for my age in the UK I think, I'm familiar with both metric & Imperial measurements, but generally fairly bad at converting. Except I know 568ml = 1 (UK! Not US!) pint - for which I can thank my alma mater Imperial and its student bars: Metric, and FiveSixEight. I could probably guess effectively at lbs and kg from butter/flour. Of course I know 2.54cm = 1". A yard is 'a bit' less than 1m. It's the bigger ones that seem more obscure/are harder to work out from familiarity I suppose.)
1. I think with liters, people typically reverse the relationship so it's liters/100km. Which is a much more intuitive unit.
2. If you're buying gas in liters, I think it'd be a lot easier to switch over to using liters for efficiency. You may not be able to compare easily to other vehicles, but you'd be able to estimate your personal fuel more easily.
I think it's the other way around. Distance per quantity of fuel is the intuitive measurement that humans understand and can relate directly to how much fuel they purchase. It could be argued that it is less intuitive when comparing two cars, however. Although better MPG is still strictly better, which is about the level of detail most non-nerds care about.
Only since the 1958 International Yard and Pound Agreement tho. Before then the US used what is now known as the Survey Mile, which is why the survey mile exists (and survived until this year).
Ironically, we live in a world where all the diversity that used to exist and has been destroyed by these zealots for corporate oligarchs, could have easily been dealt with through computers. We could have had cross-referencing systems that automatically and seamlessly work with any unit of nature, but instead the authoritarian impulses have only gotten worse over there last 100 years and actual, real diversity among humans in every domain is critically endangered.
If someone needs a concrete example, the EU (and the template, the post Civil War US) is a good one. It’s authoritarian, illegitimste by any reasonable definition of democracy, is trying to eradicate and stamp out diversity in Europe, a place that used to have the highest density of human diversity for essentially all of human existence. Millennia of diversity is currently being eradicated in Europe (in America it has largely succeeded) and the EU and its authoritarian dictatorial bureaucratic machine is the primary culprit. While you and your smug and self/righteous indignation about the use of liters is a warrior in the eradication of diversity on the whole planet. As you said, “Everyone else just uses liters” … there will be no diversity once you are done.
There'll be plenty of diversity left, trust me.
The entire world uses metric units apart from America, Libya and Myanmar. https://worldpopulationreview.com/country-rankings/countries...
What I absolutely love about this fact is that America is still using British Imperial units. After literally having a war over whether or not the US should be independent of British rule, you're still holding on to our measuring system despite the rest of the world moving on.
They were standardized separately, and vary slightly to considerably from the British Imperial counterparts.
Well, my 12 years old (gas) Honda Fit does +40MPG being very "pedal happy" and near 50 driving normally, and my dad's 20 years old (diesel) Citroen Xsara Picasso does around 60MPG
https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform...
3.9l/100km in a Xsara, really?
https://www.advantagebmwhouston.com/2022-bmw-3-series-fuel-e...
My diesel 3 series (2.9 litre, late 90s design) would get 8.83 L/100 km (32 mpg UK, 26 mpg US) driving round town, stopping at traffic lights and averaging <20 mph and never getting past 3rd gear. This didn't require much care, just a question of not trying to accelerate too hard at low RPMs or doing a 0-60 run from every stop.
Engine technology will presumably have moved on in the past 25 years, and efficiency will have improved, but you'll still get crappy fuel economy for stopping and starting all the time.
Very few people check the facts, and the only reliable way to know yourself is to take notes at the pump: gas pumped vs km travelled. I did check for a while and the numbers were quite different :-)
On a related note, for the VW ID.4, the manufacturer states 17kWh/100km which is actually achievable (much to my surprise) in city driving when it isn't cold. My real numbers are closer to 21kWh/100km. This goes up really quickly if you exceed 130km/h.
Electric motors are very efficient, regenerative braking helps, EVs are designed to be super aerodynamic, etc.
Particularly German made ones, for some reason.
I guess if you care about panels gap and not performance, go ahead and get a Brokeswagon?
I will, and "Brokeswagon" marks you as a Tesla-Musk tech-bro from a mile away...
I do wish my Model 3 LR would actually go 358 miles on a charge, that's for sure, but it would have to get even lower Wh/mi than Tesla claims on the Monroney sticker. I suppose that's not the most egregious lie on Tesla's web site, however.
The 3 and Y is even more efficient, mostly due to size. But it has a smaller battery, I can get about 69 kWh out of my AWD 3 after losses and it hovers around 170-189 Wh/km at 120 km/h and 130-140 at 90.
What is also missing here is that it takes 20-30% of energy to refine diesel or gasoline plus there is oil extraction cost. Accounting for that electrical car produces less CO2 when electricity comes from a modern coal plant than a diesel car.
https://www.caranddriver.com/news/a15341744/the-prince-of-pa...
Having said that, my 13-year-old normal sized diesel car does 60mpg in normal use.
Luckily, most people don't charge their teslas with coal power.
The problem is that at that point liquid hydrogen already spent 70% of the energy stored in it (80% efficiency of electrolysis * 40% liquefying efficiency) .
This of course doesn't include losses in transmission from the power station and in electricity production.
- AC converted to DC (with power factor correction, usually means AC stepped up 1st)
- DC converted back to AC (but higher voltage) and MUCH higher frequency
- AC transformed to lower AC voltage (still higher frequence)
- AC rectified to DC (filtered and stabilized), DC voltage lower
That's it. A pretty simple system.
That's not very good, my LPG car runs on average around 25km/l and around 30km/l on gas, albeit being a 10 years old model.
Modern diesel cars run on average at over 20km/l, the Citroen C3 does ~30km/l.
This is because you're not comparing the same things: going from thermal energy to mechanical energy has a much lower efficiency than going from electricity to mechanical energy. But that electricity has to come from somewhere, and most of the losses happen at the electricity generation place instead of in the car.
> It just wouldn't have been possible to run cars on batteries without this efficiency bump.
Electric motor have always been far more efficient than ICE ones, even in the 19th. In fact, the difference was even bigger, because combustion engine sucked hard back then, whereas electric engine didn't make as much progress as combustion engine ones (that doesn't mean that they didn't make progress, they did, but there's far less of a difference between an electric engine of 1920 and the one in a Tesla, than between an ICE engine then and now).
The difference is like the difference between carburetor engines and direct fuel injection.
And these are still more efficient than most combustion engines *today*, that's exactly my point.
Are American diesels this inefficient?? Looking at pictures online the Chevy cruze doesn't seem like a bigger/heavier car than a Passat, so what gives??
Although I completely forgot it existed. There are not many diesel passenger cars on US roads. Diesel is consistently more expensive than petrol here.
Even my 15 year old diesel car had an efficiency of 1/22. Adjust you driving style and I'd get 1/25. Range: 1000km, with an ordinary sized tank.
It seems Americans haven't even started with efficiency, quite likely because there was no pressure to do so due to low fuel prices. Not in their homes, not in their cars, not anywhere.
Do you realize that other brands and models exist in the USA? Do you realize Tesla is and American company? Did you even check look into Chevy Cruze's mileage? Here's a guy getting 70mpg in a Chevy Cruze by driving 55mph on the highway. That's 30km/l.
https://www.caranddriver.com/news/a15341744/the-prince-of-pa...
For diesel, this is really really bad. Most gasoline cars will run more economic than this, let alone diesel. If your diesel runs less then 17 to 18 km/l something is wrong.
(my opinion is based on how things are in .nl, other parts of the world can and will be different of course)
We should measure efficiency based on that number.
Still, your point stands.
The measurements outside North America are reciprocal, e.g. 7.7L/100km (which is awfully inefficient for a diesel, normally it should be around 5L)
So converting gallon to liter, and mile to kilometer is the wrong way to present it.
As for the efficient in general - of course electric engines have a very high efficiency (in the 90s), unlikely diesel which can barely hit 35%.
Meanwhile, fairly common cycling parameters lead to well under 10 Wh/km at comfortable cruising speeds, and with things like velomobiles you kinda start around 5 Wh/km, and 3 Wh/km is possible without significantly compromising the practicality of the vehicle.
Sure, sure, lower speeds, lower cargo capacity, lower safety, &c. &c.
But it’s still a useful comparison to contemplate, especially when considering the nascent category Lightweight Electric Vehicles, which in its most interesting form isn’t far off “ebike minus pedals”. Cars are still pretty power-inefficient as a general concept.
On top of that, they have more efficient components. When you compare a model S to a lightweight Carbon Fiber BMW i3, with a much smaller pack, you’ll see that the modelS still squeezes out a higher mpgE rating.
https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=46207&...
It's better to use real world highway range which is 300 miles (482 km) in a Model S:
It would be slightly worse in colder climates. I wish car manufactures would allow for easy installation for range extenders in the front trunk. I'd be a great source of heat for the heat pump. Range anxiety would be gone. No carbon tax since it would be an aftermarket solution.
It seems Mazda MX-30 r-ev is the only thing you can buy.
Range anxiety is an affliction more common among those who do not drive an EV than those who do.
That is a tautology... "Those who weigh the downside more remain in the alternative option." What did you want to mean?
A lot of people with range anxiety probably use an EV with little to no impact in their driving habits other than plugging in when they get home. But they're so concerned with "what if's" that rarely ever come up in their lives. "But what if I suddenly need to drive across the country taking only back country roads and avoiding all highways across the furthest north roads in the coldest of winter?? Can't do that in an EV!"
The most common reactions I get to people asking about my EV are along the lines of "But how do you charge it? Don't you have to wait at public chargers all the time? It must be so challenging driving an EV with so many broken chargers all the time! You must have to wait so long all the time for all that charging, its so slow!" Which is quite strange, because the vast majority of charging sessions most EVs would probably experience are plugging in at their home entirely negating these concerns.
For a lot of those people asking me those questions (often friends and family), I know they'd be able to replace a car with an EV and have only positive impacts other than the costs of buying a new car (something they do on some schedule regularly). But the talking heads on the TV tell them EVs == slow, unreliable, expensive charging so clearly all EV owners must be dealing with largely unavailable, unreliable, expensive, slow charging all the time. When in reality I spend more time pumping gas in my ICE than I do waiting on my EV to charge, I've encountered more broken gas pumps than charging dispensers in the last year, and it costs me almost 10x less in energy cost than my ICE per mile.
All that extra energy ICE cars carry isn't actually being put to use very well. They don't have more powerful engines. They don't have more torque. They don't have more acceleration. And even their range isn't that much better. You can of course get models that take something like 100+ liters of petrol. But the per liter performance only gets worse if you do that (heavier cars are less efficient).
The reality is that yes, fuel is very energy dense but sadly most of that isn't transformed into motion when you use it. You are instead making lots of noise (vibrations) and heat. Both are actually bad for your car. So, you use most of the energy to wear out your car faster. The more powerful the car, the less efficient they are. And the faster they break down.
Earth's Lithium deposits.................. 88,000,000,000 Kilograms [2], [3]
@25% Viable for mining.................... 22,000,000,000 Kilograms [2], [3]
Tesla S battery weight.................... 540 Kilograms per car [4]
Lithium weight per Tesla S battery........ 63 Kilograms per battery [4]
Max Tesla S (global) production possible.. 349,206,349 units (See Edit below)
Number of automobiles running in the USA.. 102,000,000 units [1]
Number of automobiles running in the World 1,500,000,000 units [5]
So, even if we theoretically assume that the earth's entire known Li reserves are used for EV usage, we cannot replace more than 25% of the currently running cars in the world.
So, we have a bigger problem ahead of us (over the next decade) that will act as an opposing force against EV penetration and replacement of the IC engine.
Solutions possibly lie in exploring other battery chemistries while improving the efficiency of Li extraction.
Edit: As some of the comments below point out, the Li content in a Tesla Model S battery is approx. 63 Kg. That makes the Max Tesla S (production) possible to 349 million units. So, in theory, one could replace all IC engines in automobiles plying in the USA. That then leaves the rest of the world. So, the problem still remains.
[1]: https://www.fhwa.dot.gov/policyinformation/statistics/2021/m...
[2]: https://www.popularmechanics.com/science/energy/a42417327/li...
[3]: https://www.usgs.gov/centers/national-minerals-information-c...
[4]: https://blog.evbox.com/ev-battery-weight
[5]: https://www.weforum.org/agenda/2016/04/the-number-of-cars-wo...
Even if they couldn't, why would you limit your analysis to Li-based batteries? It's basic economics that when a resource becomes rarer, it becomes more costly and alternatives spring up. EVs with Sodium batteries are already on the market in China. This whole Lithium fear mongering is such a red herring.
> Solutions possibly lie in exploring other battery chemistries while improving the efficiency of Li extraction.
I'm also going to say that all the car companies, battery companies, and governments in the world probably took six seconds to do basic math before investing trillions of dollars in it.
It doesn't, because that 88,000,000,000 is a lower bound amount of lithium on the planet not an upper bound.
If I count all the apples on the apple tree in my yard, I haven't counted all the apples on the planet. Only the applies I know about. There's probably still more apple trees out there!
That 88,000,000,000 figure also doesn't count any lithium in the oceans. Taking even a small fraction from there would make that 88,000,000,000 seem tiny.
More broadly, this is a class of complaint that you can't see every detail of path and the destination from the very beginning of the road. The solution to that isn't to stand around and complain about it, but _start moving towards the destination_.
A quick google returned this ~63KG
https://electrek.co/2016/11/01/breakdown-raw-materials-tesla....
Remember peak oil, which was a big panic of some in the 2000s? It turns out that peak production didn't happen overall, but if you look at the original set of "known resources", the peak oil predictions were spot on. Yet we didn't experience huge oil supply shortages because huge expenditures into new fracking tech enables far more resources to be accessed.
We have always loved in a complete abundance of lithium, so we never bothered to look for more resources. Now that we need more, we will find it. It's not a particularly rare element.
Emphasis added from your [3].
Ever think maybe your 88,000,000,000 Kilograms number isn't actually all the lithium on the planet, and maybe there's more undiscovered under the ground? Or do you think all the lithium on the planet was discovered in 2023, and now there won't be any more reserves found?
Strange how this maximum amount of lithium reserves keeps magically growing year over year over year over year. I wonder how it magically appears.
mpg = miles per gallon
Gasoline is rather energy dense, but the ICE is rather wasteful. There is a certain base load of energy being generated by an ICE engine, regardless of if you are moving or how slow you go. This is why carmakers experimented with things like rapid stop/start engines, regen batteries&motors, etc.
ICE becomes more efficient as you reach highway speeds, which is why highway mpg is better than city mpg.
Batteries by contrast are not very energy dense, while EV motors are extremely efficient. The only energy being consumed is that which is needed to move the car, plus fight rolling & wind resistance, and power AC/heat. Wind resistance increases with the square of speed.
EVs as a result are most efficient at low speed, and at highway speeds become noticeably less efficient as you go from 55->65->75mph. This is also why running AC/heat has a noticeable impact on range in EVs.
An ICE car traveling at a constant 30mph is going to get much better fuel economy than an ICE car traveling at a constant 75mph. The difference is that <=30mph roads usually have a lot of stop-and-go.
ICE peak efficiency tends to be more around 45mph than 30mph.
But yes, the less you brake in an ICE, the more efficient. Hybrids give you a bit of the ICE range/highway efficiency with the EV city driving efficiency, with the added complexity of having ICE & EV under one hood.
If we really cared about efficiency, we'd have smaller motors. Throttling decreases efficiency, so the best mileage is going to be cruising at WOT (naively assuming no fuel mixture enrichment, which isn't always true). A classic example of this strategy is an old Geo Metro. Light, tiny motor, and barely capable of maintaining highway speed using peak horsepower.
You can make an EV that is as fast as a Porsche but highway cruises like a Prius. It's up to the idiot behind the wheel if they prefer to go fast or go far.
I remember in high school my "fast for a regular car" Pontiac did 0-60 in about 7sec. This is achievable in a Nissan Leaf or Chevy Bolt now. The most low price, vanilla and dated tech in EVs you can buy.
EV buyers will quibble about 0-60s in the 4 second range that aren't even sold as "performance". You used to have to buy a BMW of M designation to achieve these types of numbers in a 4 door sedan, and get the horrible MPG along with it.
The chunky hatchback crossover MachE GT Mustang EV is faster than an ICE Mustang Mach 1 which gets a mid-teens MPG..
Teslabjørn has a video where he turned his Model X into a sauna getting 40⁰C inside while it was -10⁰C outside.
But being in Northeast US with constant traffic.. I used to have to park outdoors so the car would get cold soaked down to 20F in winter, and never really have sufficient time to warm up unless I was going for a 1hr+ drive.
Winter driving local roads, below-25mph stop&go, 2-5mi trips running errands.. Could see some really crazy consumption numbers pop up like 500-800Wh/mi+ versus the rated 250Wh/mi. Now it doesn't necessarily amount to much because it's on short single-digit mile trips, but it does happen. This stacks with the general cold weather efficiency losses of EVs..
That's true. But I've never had anything like 800 Wh/mile in my Model S 70D not even pottering around at -20°C
Not a mark against EVs of course - it kind of just makes sense. I'm sure future generations will laugh that every vehicle used to have its own on-board power generation facility. It's too bad the dumb power-plant-under-hood way is still so much cheaper than the EV approach of course.
Porsche Taycan: 2 miles per kWh
Tesla Model 3: 5 miles per kWh
Lightyear Zero: 7 miles per kWh
Aptera: 10 miles per kWh
The Aptera gets 0 miles on a 0 kWh battery because they've shipped 0 cars, right? Can I go buy one and drive it today?
Sure, they failed in the past but they have the money now and they've certainly shown they won't give up.
Gets, as in present tense. A theoretical car made sometime in the future shouldn't use present tense terminology. No consumer on the road today is getting 1,000mi on a 100kWh battery in an Aptera. If Aptera manages to actually ship cars, then the word "gets" is accurate.
> What makes you think it won't get to market?
See:
> Sure, they failed in the past
Building cars has extremely high barriers to entry. Getting things approved costs tons of money. Spinning up factories is no small challenge. Actually making more than one or two cars is incredibly challenging. Meanwhile, in order to spread those costs out you'll hopefully want to make a lot of them otherwise a good chunk of your value proposition goes away as the costs for the car would quickly get out of hand.
Then comes the challenges of actually selling them at any volume. I legally can't buy one in my state if they don't create a franchise dealer network. Its hard to get shoppers to compare your vehicles if you don't have a way for them to actually buy the cars. Tesla manages because they spent a ton on "galleries", they were the only real EV option for a while, and have massive brand presence. Ask any random average car buyer if they've thought of buying an Tesla, and they'll probably have an opinion. Ask anyone if they've thought of buying an Aptera, and they'll probably have no clue what you're talking about.
If Aptera manages to actually make some cars, that's great! Even better if they manage to sell them for profit. Its good to have more competition. But I'm not holding my breath.
A normal diesel fueled sedan such as the Chevy Cruze diesel runs at about 31mpg, which is 13.2 km/l or 15.3 km/kg. Diesel has a mind-boggling 12700 Wh/kg energy density[1], which translates to an efficiency of ~827 Wh/km for the Chevy.
By contrast, the Tesla Model S, has a ~540 kg battery[2]. At 272 Wh/kg (from the posted article), that's ~147 kWh of energy storage, and the Tesla can do a rated 650km on a single charge[3]. So that's an efficiency of ~225 Wh/km, which is ~27% of the energy required to run a normal car!
It just wouldn't have been possible to run cars on batteries without this efficiency bump.
1. https://chemistry.beloit.edu/edetc/SlideShow/slides/energy/d...
2. https://blog.evbox.com/ev-battery-weight
3. https://www.caranddriver.com/tesla/model-s