A Real-Life Tesla Study Shows Durability of EV Batteries 124
Slashdot reader Rutabaga8 is the CEO of a web site conducting in-depth research on personal finance topics. They recently contacted Slashdot to share "some surprising results" from their analysis of a nonprofit advocacy group's seven years of data on Tesla batteries:
By seven years of age, the typical car could still deliver around 93% of the original range on a full charge. That means a Tesla battery typically loses around 1 percentage point of range each year on the road.
Of course, cars that put more miles on the odometer are likely to get faster battery deterioration, because it's the number of charges that really impact battery degradation. However, the data showed that by 150,000 miles Tesla cars still achieved more than 85% of their original range when they were charged to full capacity.
Of course, cars that put more miles on the odometer are likely to get faster battery deterioration, because it's the number of charges that really impact battery degradation. However, the data showed that by 150,000 miles Tesla cars still achieved more than 85% of their original range when they were charged to full capacity.
Why doesn't tesla just publish their data? (Score:1)
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They've got all the data. It'd be useful if they'd publish it.
Uh... they pretty much have. And the fact they offer an 8 year unlimited mile warranty pretty much says they are not worried about batteries failing at all.
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And the fact they offer an 8 year unlimited mile warranty pretty much says they are not worried about batteries failing at all.
8 years is two years shy of what Hyundai offers, on cars most people can actually afford. It demostrates Tesla is more worried about the batteries/electronics degrading due to old age than due to wear and tear.
Obviously, this doesn't matter to people who get rid of their cars before it ever becomes a problem. But we can already see today with the oldest Nissan Leafs what happens to EVs when it's no longer cost effective to replace the battery. Tesla may take a bit longer to get to that point due to their
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As for the Leaf, what
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Many of y'all seem to forget the cashiers, burger flippers, and (in my neck of the woods) theme park employees, need to be able to get to/from work, too.
And you seem to forget that those people can't afford to pay for gas, oil,
or mechanical repair bills where EV owners never do,
Y'all.
Mild Surprise (Score:1)
Well... color me mildly surprised! I'd figure these EV batteries would have deteriorated by at least 20-30% if they are at least 4 years old, similar to current smartphone batteries.
Perhaps there is some hope for EVs in extreme conditions.
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Smartphone batteries use cheap chemistry.
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And good EV batteries also have sophisticated battery management systems, which wouldn't be practical or cost effective in a smartphone.
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It would be simple enough to have some software in the smartphone that avoids full charge/discharge, which would already help a lot.
optimized charging in ios13 (Score:2)
Re:Mild Surprise (Score:4, Interesting)
Smartphone designers OTOH seem determined to make the battery as small as possible, which forces them to use their full capacity (100% to 0% depth of discharge) to give you enough battery life to make it through most of the day. This kills the battery within several hundred cycles, which for most phone users is 1-2 years. This is why a lot of us have been campaigning for user-replaceable batteries, or phones with enough battery capacity to last 2-3 days. The battery on my previous phone (Nexus 5) died after just 13 months of me using it heavily from 100% to about 5%. Google replaced it under warranty, and I was careful not to charge the second one over 90% whenever possible, and to always recharge it before it dropped below 25%. That one lasted 3 years without any appreciable drop in battery life.
Unfortunately, Tesla won't say how deep their discharge depth is. Which makes the stat given in TFA kinda useless. Without knowing the depth of discharge, we have no way of determining if their batteries are performing the same as those in other EVs, better, or worse.
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Teslas batteries are pretty well managed by the sounds of it. Their discharge, charge, temperature and voltage are all carefully monitored/controlled. Your smartphone, laptop and even some other EVs do little if any of this which results in drastically decreased lifespans. Imagine if your car engine was air cooled (no radiator) and you routinely revved it till it hit the limiter, that is a little like what it is like for a battery pack that is ran from 0 to 100% regularly, charged at full power every-tim
Years of age is INTENTIONALLY useless. (Score:1)
Let's see hours of actual usage and number of charge-discharge cycles.
Plus how much of their maximum achievable charge/discharge you charge/discharge them.
Re: Years of age is INTENTIONALLY useless. (Score:2)
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No, you are wrong. Car buyers won't measure the car battery life in discharge cycles.
If a would be car buyer goes into a dealership, they would enquire about the discharge cycles before they might have to replace the battery. They would want to know how long in years, or in miles driven, it would be before they might need a new battery, which would give them an idea of the cost per mile, or per year, of the battery.
If you want blank stares, ask a random phone user about battery discharge cycles.
More useful (Score:2)
So a 40,000 dollar model three will have a range of closer to 200 miles that 300 miles in 7 years, given the real world test put the new range well below 300 miles. This is likely not an issue if you can charge
Re:More useful (Score:4, Informative)
Data collected for Teslas suggests that your assumption is not valid. Most data shows a drop in capacity of about 5-7%, over the first 50,000 miles, followed by very little drop in capacity over much longer distances travelled.
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Actually you can charge a Tesla Model 3 LR from 10% til 60% in just 12 minutes at the Ionity 350 kW chargers (although the car only charges at 200 kW). 20 minutes will get you to 80%. You will not charge to more than that if you want to go fast.
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Would it be a linear decay if you're using percentages?
Dafuq with da fones? (Score:2)
Don't even get me started on an electric razor's lifetime. First one I had lasted maybe 20 years (2 blade replacements). It's replacement, about 4 (0 blade replacements). It's replacement is less than a year old and it's battery lasts 3-4 days (wish I'd kept the receipt).
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Phone batteries get charged to almost maximum capacity, so much that any more may let them burst into flames. And sometimes that actually happens ;). Also they are allowed to be discharged until they are on the point of unsalvability (you can ruin your Li* batteries by discharging them too deeply). And that all in sometimes abominable conditions (too hot or too cold... too fast). This probably is because in the eyes of regular consumers, time for 'untethered' operation, fast availability if you have to cha
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I'd like to see a "safe charge" mode for phones, optimized for longevity. For example, only charge to 70%, slowly. I think some laptops have that but I don't know about phones.
That would sufficient 90% of the time. Only enable full charge when needed.
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Also, when you do need full charge, allow user to set the time. For instance, if you charge your phone at night, and your alarm is set at 7:30, it could first charge it up to 80%, and then keep it there until 7:00, and then top it off.
But when it goes bad ... (Score:2)
... it can go very very bad. Local police report this afternoon of a Tesla not apparently involved in any collision that caught fire on a country road not far away. "1000' plume of smoke" reported. The occupants got out. The car melted down (fire dept couldn't do anything but watch and keep nearby brush wetted down) and took the pavement with it (was the smoke plume from the car or the asphalt burning?). Cleanup request was for a wrecker that could transport a "melted Tesla" and keep it at least 50' away fr
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Can you provide links to the report? Or pictures? It's not that I don't believe you, I'm just curious on how this was reported and what the melted car looked like.
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Was at a real-time dispatch log web site maintained for the media, and I saw it after they had already called the tow, so it's gone by now. http://cad.chp.ca.gov/ [ca.gov] Not a news story. Was on Fry Road/Lewis Road, east of Vacaville CA (Golden Gate dispatch center, also showed up in the statewide "hot spots"). FWIW, I also saw in passing a collision not too far away from this incident, where a Tesla was involved in a multi-vehicle collision on I-80; there was no fire (as is usual, which is why the fire report w
False impressions from news selection bias.. (Score:5, Informative)
The problem with this is that Tesla fires are rare, so they are news, while gasoline car fires are common, so they aren't news. So if you judge by number of news reports, Teslas have a bigger problem with fires, even though this is completely the opposite of reality.
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Common isn't the word you're looking for.
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I have seen 3 too, that already makes 6 total. I'm sure we can find a few more people.
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Let's do some quick math.
Let's say 3 car fires in 20 years is a normal rate of fires for a person to see.
Let's say that the standard Seattle morning/evening commute people (274k vehicles... significantly more people, but we'll stick with vehicles) saw these same 3 fires.
That's 3 fires out of 1,424,800,000 commutes, or 1 fire every 47,493,333 commutes.
Now I'm not sure where we need to draw the line for rare, but 1 fire every 1,234
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17 gas car fires per hour [businessinsider.com]
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So you then use *all* routes to highlight... what exactly?
Your argument can be used to say that being hit by lightning is common.
At a large enough scale, all things are common.
If current Tesla car fire statics were extrapolated to 275 million Teslas on the road making as many commutes as car drivers make, Tesla fires would be "common" by your definition of that word as well.
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From 2012 – 2018, there has been approximately one Tesla vehicle fire for every 170 million miles travelled. By comparison, data from the National Fire Protection Association (NFPA) and U.S. Department of Transportation shows that in the United States there is a vehicle fire for every 19 million miles travelled.
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1 fire every 19 million miles traveled.
All things being equal, and extrapolated- that's 2 Tesla fires per hour instead of 17. It's absolutely better. I never intended to argue that it wasn't better.
My point was that's not common.
And futher more, 1/8th of common certainly isn't "rare"
OP was making a sales pitch, not an informed observation.
Re:False impressions from news selection bias.. (Score:5, Informative)
181000 cars catching fire per year isn't the definition of rare either.
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How many of those commutes involved no fires?
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'Only ever seen 3 car fires.'
"Each year, from 2014 to 2016, an estimated 171,500 highway vehicle fires occurred in the United States, resulting in an annual average of 345 deaths"
https://www.usfa.fema.gov/down... [fema.gov]
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You're using the law of large numbers to argue for the commonality of a thing, and that's ridiculous.
Perhaps we should expand it hypothetically to the entire Universe?
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So what you're saying is gasoline powered cars never catch fire?
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You think that's bad, my dad's ICE car caught fire, and he was daft enough to drive into a petrol station. Fortunately he had the foresight not to park near the pump, and only needed to grab the extinguisher. He nearly became a statistic of the number of petrol stations to burn down. Instead he became one of these statistics: https://www.statista.com/stati... [statista.com] specifically one of the 395000 cars to catch fire in 1996.
But we've gotten better. Only 181000 cars caught fire last year in the USA.
1000' plume of smoke
In related news,
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His though-process might have been along the lines of :
"If anybody knows how to put out a petrol-fire, it's gas-stations - right?"
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Along the lines of a truck on fire pulling over beneath an overpass. At least one of those, in LA, resulted in enough damage to the bridge to require it to be demolished and rebuilt.
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FWIW I was looking at a police media log, not a news report.
As for ICE fires, yes, there are lots of them. Far more than there should be, even considering the vastly larger number of ICE vehicles around compared to battery (or Tesla). But road damage isn't common for gasoline fires, nor is a melted car. Burned-out hulk, yes, but not melted, unless the fire gets help from vehicle contents or something else involved in an accident (a diesel truck?). OTOH, diesel fires do produce meltdowns and road damage - th
Real life? (Score:2)
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You didn't exactly offer anything either. (Score:1)
He *may* have his sources.
You *definitely* have none. (Since you made no statements regarding this, in the first place.)
Re: You didn't exactly offer anything either. (Score:2)
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Second guy only needed one source to back up his assertion: the post he replied to.
Next time let your brain churn through a few more cycles before jumping to the defense of one of your pet hatreds.
(Yes, your posting history makes your viewpoint quite clear. What's disappointing is you're apparently willing to throw out all intellectual dishonesty to support that viewpoint)
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"Who cares if he may have sources. He didn't give any reason to believe he did."
Reasons? Nowadays we have feelings.
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"He *may* have his sources.
You *definitely* have none."
Why should we believe a guy that has no shoes?
Re:Sorry (Score:5, Informative)
What are you smoking because I could totally use some of that? If you actually went to the Tesla website for their used inventory, none of the vehicles list remaining battery capacity or "half" the range. Maybe you're confused by the earlier Model S 60 with their 210 miles range vs a current Model S 100.
Re: Sorry (Score:2)
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Re: Meanwhile... (Score:3)
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Also, it's much harder to kill yourself in your garage with an EV, stupid EV fanboys!
I'm not sure I believe you. Could you perhaps show this with you performing a practical demonstration?
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a practical demo would be to put both cars in a separate enclosed space like a garage, close the doors and turn the engines on and see who fights to get out first
That does sound like an interesting demonstration but how do cars fight to get out of a garage? Especially if the cars are in separate spaces?
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"Also, it's much harder to kill yourself in your garage with an EV"
Worse, some of them won't even allow you to run over your mother-in-law.
Re:Meanwhile... (Score:5, Insightful)
You must have a magical gas engine that never needed a tune up. Every gas car I've own has had worse mileage over time even with tune up.
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You can tune an IC engine and not need to replace it. Also, the overall range of an IC engine does not plummet like a Tesla does in cold weather. I have had many cars go from new to 150 to 180k with only a few percent drop in fuel efficiency. Perhaps you need a better mechanic?
Re: Meanwhile... (Score:3)
Winter Gas, cold engines for our cars. Dense air (Score:2)
Cars DO get better mileage I the summer. Cold engines get worse gas mileage. It takes a while to the engine up to today optimum temperature when it's cold.
Summer blend gas also has a bit more energy.
Of course, for racing or speed records you want to burn MORE gas to produce more power. It's easy to pump in as much gas as you want, the difficult part about a powerful engine is moving as much air through the engine as possible. The air needs to weigh 14 times as much as the gas. That's why you have hood s
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I had a car that slowly got better as time passed after a tuneup. As the cam in the distributor wore it caused the timing to advance.
Modern gasoline engines don't need tuneups.
As a new engine breaks in, roughly machined parts are smoothed and friction reduced.
Tires become more efficient as they wear; the thinner tread deforms less.
Re: Meanwhile... (Score:2)
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Your mandated catalytic converter will slowly cause resistance to exhaust, draining your horsepower. Over time, it will quickly outdo any gains from the advancements you said.
Not unless it breaks. Otherwise it burns away over time and becomes less restrictive.
Also, engines break in at 500 miles typically, and some are sold already broken in. So that can't account for efficiency gains over significant time.
Two good pulls breaks in an engine. Literally.
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"Your mandated catalytic converter will slowly cause resistance to exhaust, draining your horsepower."
Not to mention that the gas guzzlers complain about EV lithium use while they have to coat their catalytic converters with platinum inside, just to treat the poisonous gases that come out the back.
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No, it didn't. As the cam wears, the timing will retard, not advance.
Re: Meanwhile... (Score:2)
I recorded weekly average MPG of all my 2010 Honda since mile 1. 168000 miles, same MPG
Comment removed (Score:5, Informative)
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I can assure you that at 150k miles, there will be a reduction in engine compression (piston ring wear) and reduced airflow from carbon deposits.
I can assure you that this loss of mileage will be so small as to be barely noticeable.
Much of this will no doubt be because the range at the start will be quite high, compared to electric equivalents. Much of this will also be because the refill time is so small. Much of this is also because people don't think so much about how many miles have passed but more on how many hours (on a long trip) or days (for the daily commute) since they last filled up.
The day to day mileage variation is quite possibly hig
Re: Meanwhile... (Score:4, Insightful)
I can assure you that this loss of mileage will be so small as to be barely noticeable.
Having owned a lot of ICE cars well past 150k, I can assure you it is not an unnoticeable loss of milage... and performance.
If it were truly un-noticeable why would anyone ever rebuild an engine? And yet going in to clean out cylinders and replace piston rings is pretty common past a certain point.
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I can assure you that this loss of mileage will be so small as to be barely noticeable.
Are you going to put more to that assurance other than words?
I believe your claims of reduced fuel economy from 150k miles is based on cars from decades ago.
You'd be wrong. We didn't magically eliminate wear in engines. Car engines still require massive amounts of maintenance to even approach factory new fuel economy, and the economy hit can be quite significant well into the double digit percentages. Worst I've ever seen in the garage at our work was a 50% increase in efficiency. It took the guy 3 days to tune up the engine, replace basically every soft component and several of the hard ones too. Cos
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I've got an Audi with a 4.2 V8 that has like-new compression, and the cylinders are still literally as smooth as a drinking glass. The valves are still shiny. It's got 225k miles on it. Granted, it's got an alusil block. Also, it has to have a timing belt (etc.) every 90k, and getting the same mileage as new means it only gets about 18 MPG combined, so there's still clear advantages to EVs.
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What prompted the engine disassembly so that you could see the cylinders and how much did that cost?
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Oil leaks. I did both head gaskets, cost me some $200 in parts. Quite annoying. Like I said, EVs have their advantages. But if you're not afraid to learn, you can do this stuff yourself.
I'm getting rid of it, though, and keeping my 1982 300SD, so I can put its engine in a Jeep someday. Audi is discontinuing parts left and right, I want to get out while it's still worth something... however little.
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You mean that V8 that has the timing chain against the firewall and needs an engine out service at 100k miles?
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No, this is an ABZ. It's a 24V motor with a timing belt at the front, and you don't have to pull the engine unless you need to do the rear main seal or transmission front seal. It does however require stupid tools to do the timing belt.
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"I've got an Audi with a 4.2 V8 that has like-new compression"
Small wonder, that's the fraud motor, it does that by killing young and old people's lungs.
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It's a 1998, it barely has emissions controls. It's got two catalysts and four O2 sensors, and a valveless PCV system, and that's it. And it passes the California emissions test with flying colors.
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...and I just sold it. now I can stop talking about it. Right after this: It does that by using an alusil block and synthetic oil. Alusil blocks are the business, although if you have them bored out you have to do special stuff to the cylinder to refinish it. Basically you have to run a special hone through it that removes the aluminum from the surface, but not the silica.
Re:Meanwhile... (Score:5, Insightful)
Meanwhile, my gas engine still gets 100% of the fuel efficiency it had when I bought it while EV fanbois are applauding 85% range.
So it gets 100% of the 25% max efficiency for a combustion engine? Not much to brag about. And pro-tip: you're not getting anywhere near 100% of new-vehicle efficiency after 7 years.
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And pro-tip: you're not getting anywhere near 100% of new-vehicle efficiency after 7 years.
Fucking poppycock.
Sure, some motors after 7 years have compression leaks or other not-simple-fix problems that do degrade efficiency measurably, but literally every vehicle I have ever driven the wheels off of kept the same mileage up until an identifiable problem occurred that would cause it to not. At which point I fixed it, or pitched it.
You know, you're right that the efficiency of a carnot cycle engine is shit. But that doesn't excuse you making shit up.
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Re: Meanwhile... (Score:2)
Honda accord 2010, recorded weekly average MPG since mile one - no change
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Pro-tip: Stick to what you know...
Take your own advice.
You're blatantly wrong about basically everything EV-related that you wrote up to and including comparing vehicle safety.
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And I bet it hasn't lost any compression either!
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"Meanwhile, my gas engine still gets 100% of the fuel efficiency it had when I bought it while EV fanbois are applauding 85% range."
Only that they lied to you about the fuel efficiency.
You fail to mention that now it needs a quart of oil every 100 miles and that you had to exchange dozens of pieces and filters and pumps to get to that point.
And the Tesla is _still_ faster than your Porsche.
Not quite 100% of the fuel efficiency (Score:2)
Actually, a gas-engine car may initially increase in fuel mileage after you drive it off the new-car lot. Friction may diminish as the engine wears somewhat, and the fuel and spark management algorithms may adapt to your driving pattern.
At high mileage, you may see noticeable degradation in mileage. The engine may start ingesting lube oil. I was told by a graduate student doing research on this that even a tiny amount of inducted oil can cause a spark knock. The catalyst may plug with soot from this
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You sure like to type a lot of rubbish.
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I'm rather tired of people talking about the problem but not talking about solutions, and the rare cases I do see solutions they often involve elaborate and expensive shifts in technology when there are far more practical solutions already available.
If people are serious about CO2 emissions from transportation then we'd be putting money into bringing existing and affordable technologies into large scale, not wasting money and precious time on replacing everything we have with something untested and quite li
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The problem with synthesized fuels are that they're not an energy source, just an energy storage medium. In order to synthesize fuel in the first place you need to put more energy into it than you're going to get out - and synthesis efficiency is usually not great. And that energy still needs to come from somewhere. Fossil fuels provide access to energy stored millions of years ago, synthesized fuels need a solar, nuclear, etc. source to generate the energy being stored in it.
There is a lot of potential
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The problem with synthesized fuels are that they're not an energy source, just an energy storage medium.
I believe that to be irrelevant if the alternative is batteries, which are also only a means of energy storage and not a source of energy.
In order to synthesize fuel in the first place you need to put more energy into it than you're going to get out - and synthesis efficiency is usually not great.
Also not that relevant if the alternatives are CO2 emitting petroleum fuels, similarly inefficient biomass fuels, batteries that won't get your airplane or ship to its intended destination, and so on. We are running out of options, and as far as I've seen this is the best we got.
And that energy still needs to come from somewhere.
Not relevant because, again, the alternative offered most often is batteries.
There is a lot of potential for synthesized fuel, especially for long-range vehicles.
The only option
Re: Keep your eyes on the prize (Score:2)
I agree with the idea that synthesized fuels offer a way to go carbon neutral for those applications ( such as aviation ) where it might otherwise take decades to implement a carbon neutral solution.
However I don't agree that hybrid electric makes sense for automobile usage. There we already have a solution ( BEV ) that works. With a 300-500 mile battery and a robust charging network, I don't see the need for hybrid electric. I get that until more people get used to BEV they may PREFER a hybrid solution, bu
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I agree with the idea that synthesized fuels offer a way to go carbon neutral for those applications ( such as aviation ) where it might otherwise take decades to implement a carbon neutral solution.
If it works for aircraft then why would it not work for everything else? Maybe aircraft would be less price sensitive but then it's only a matter of the cost coming down with development and economy of scale, or people adjusting their lifestyle to match the cost. One such adjustment would be with the hybrid electric vehicle.
You pushing back on the idea of synthesized fuels only demonstrates my point on people losing sight of the goal. The goal is carbon neutral transportation, and everything that brings
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ICE engines are much less efficient than batteries - somewhere around 20% efficient, compared to 60% for EVs. And of course, the process of creating hydrocarbon fuels wastes energy, a Googling say it operates at 13.4% efficiency.
So everything you're talking about is possible. It just makes no sense in the real world, because between the two it's a less than 3% efficient way to utilize energy. Would you rather go 25 miles in an EV, or 1 mile in a gas car running artificial hydrocarbon fuel?