Why Gas Engines Are Far From Dead - Biggest EV Problems

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Dan Thomas

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People worry about fire hazards with lithium batteries or hydrogen. Gasoline is very hazardous, but of course we're used to it. Neither hydrogen nor lithium batteries pour out on the ground and spread all over the place. I suppose a big hydrogen leak indoors could cause an impressive flashover, maybe even worse than the kind you get from a smoldering couch.
People worry about battery fres for good reason. There have been numerous battery fires in EVs, even though they're claimed to be safer than gasoline vehicles. The thing is that these batteries sometimes catch fire for no good reason, in garages or whatever, while the typical gasoline fire occurs as the result of an accident rupturing the tank. And no, Hollywood is not a good source of proof of the dangers of gasoline.

https://www.motor1.com/news/399295/porsche-taycan-blew-up/
 

Voidhawk9

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Denting a gasoline tank isn't likely to be an issue unless it is severe enough to split open the metal.
Denting a battery, on the other hand, can torch your vehicle.
 

lr27

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I've been around a bunch of lipos. They don't automatically burst into flame when dented. I'll grant that they CAN burn vigorously and even burst, but it's not something I've seen myself, and it's not clear to me that properly managed batteries spontaneosly burst into flame.
Gasoline doesn't have to automatically explode, as in the movies, to be dangerous. It's reasonably easy to get an explosion on purpose, but it's not a common accident scenario.
My grandmother's car burned up. (She got out in time.) As a teenager, I spent a few days in a small engine shop, where I noticed they were a little careless with gas. A week or so after I left, the place burned to the ground. I've seen cars on fire at the side of the road. As I said, we're used to the danger, so it's not scary.
 

cheapracer

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lr27

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It's kind of amazing to me that "they" have so much control that they can arrange for 17 fires every hour (as opposed to 16 or 18). Can't they arrange for none?
BTW, I saw a figure of 19.5 in a government publication, which raises the question of how you can have half a fire.
 

PMD

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Yes, and there are many other problems with hydrogen. It is famously difficult to store (leaks through most common gasket materials/sealants, causes embitterment of steel, copper, and several other metals), and rather than being "clean" it is commercially produced using natural gas as starter stock, with considerable loss of energy compared to just burning the natural gas. (Producing hydrogen using electrolysis would considerably increase the price). Hydrogen might appear to be a useful means of transferring/storing power for electric motors, etc, but on a large commercial scale it is a road to nowhere. The "hydrogen economy" envisioned by some people was, and remains, impractical.
We already have a fantasticly simple way of storing hydrogen: we leave it bonded to the carbon it belongs with. In that way, we can save the HUGE amount of energy wasted on breaking that bond, and we can also then burn the carbon in the same diesel engine that burns the hydrogen.

The boogeyman nonsense of "carbon = bad" completely ignores the simple fact that the carbon cycle is part of the very thing that makes life of all kinds possible on this planet. The secret to sustainability is not to devise ridiculously complex ways to live the way we do, but to learn to do a lot less and more efficiently until alternative technologies are sufficiently mature.
 

BJC

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The boogeyman nonsense of "carbon = bad" completely ignores the simple fact that the carbon cycle is part of the very thing that makes life of all kinds possible on this planet. The secret to sustainability is ...
.. to have a population of animals that doesn’t exceed the natural capability of the planet to balance plant life with animal life. Even then, climate cycles will continue to be dominated by solar activity.


BJC
 

PMD

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Last time I checked, the average gasoline fueled car could go somewhat over 300 miles on a tank. The range for the Tesla I"ve seen quoted is comparable, but let's say it's only 200 miles. Currently, it takes a while to charge a Tesla, but I own batteries that can be charged in 15 to 30 minutes. Personally, after driving for several hours, I like to stretch my legs and eat something. So electric ground vehicles, or at least cars, are practical NOW. Especially plug in hybrids.

As I said, in the air it's another matter.
I always refer to diesels instead of gasoline vehicles when it comes to ideal - mostly because of the efficiencies but looking forward, due to the multi-fuel tolerant nature of the beast (I have some diesel equipment that has NEVER seen a diesel pump in their life). On the car side: I LMAO about Tesla range, as we live in a place where it gets to -40 regularly - just check the range and ability of ANY EV to deliver much at all under those conditions. When we get into our FLD120 to move 40 tons of gear, we drive the legal hours and only stop for fuel ever second day. When we get into my wife's farm beater (Q7 TDI) only good for 600 miles, but her old Jetta wagon gets used for serious high speed travel as we can run an easy 800 miles non-stop (about as long as we can stay in the seat at one stretch).

Now, I am not only an anti-EV person, but also as you can guess rather anti-gasoline. That said, I can not dismiss the most important EAB aircraft that sets the standard for how well conventional gasoline ICEs can work in an airplane, you know, that push-pull one that Dick and Jeana flew for a bit.

I won't get down to hard numbers, since they can be manipulated to death, but: the energy density of the storage medium is obviously at the very top of the reasons we choose aircraft power systems. If we look a bit further, we need to appreciate that electric motors, that we see as the only element, air usually powered by batteries that are being charged from the grid. To look at efficiencies (and emissions) one needs to appreciate that most of the power on the grid is coming from burning fossil fuels. That has a certain level of thermal efficiency, but then it must be changed in nature from thermal to electric, and that resulting voltage transformed several times so we must now multiply the efficiencies of the generators, transformers and transmission lines that get the power to the nearest sub station, where it again must drop voltage to get to the distribution network and once again down to safe voltages for the appliances to use, and once again through the rectifiers needed to run the charging circuit and finally the electric motor(s) in the EV. Taken all together, you would be lucky to see 70% of the power you started out with. Now, a current gasser could hope to see 30% with best technology (i.e. NOTHING that we use in legacy SI recips) but current tech CI (diesels) can hit 40%. I can cite a certain 182 that Soloy flew from WA to Oshkosh with an SMA diesel (already obsolete tech) on stock fuel tanks setting first a distance record, and then loitering for nearly another HOUR before landing.

So, it is easy to see that the current level of technology can do things that EVs in the air or even on the ground can not even hope to accomplish until there is some kind of revolution in energy storage that is not incremental, but several orders of magnitude greater than anything on the table. So, what about IC tech? Well, modern 2 cycle marine diesels top 50% energy efficiency as they are, and very light and compact opposed piston diesels can do the same thing (because of geometry of cylinder and lack of energy wasting, complex and heavy cylinder heads) as Achates Power has demonstrated in many engines now running on test stands and in test vehicles.

Now let's go on to more advanced tech that is not theoretical dreaming but already demonstrated in research projects (sorry, I have to be a little quiet about the who, how, where and when) but work with aqueous fuels and steam injection used in engines with target of dramatically reduced thermal signature (I am sure you can guess why) has demonstrated thermal efficiencies over 70%. Now go back to the start of this stumping and note what I said about efficiencies of EVs starting from the generation using hydrocarbons.
 

PMD

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I made no judgement about which method should generate the power, just that it can come from any source. BC could build gasoline turbines (which are 65% efficient) to produce the electricity. You will have losses in the transmission and storage, but since the losses would be far less than 30% and the most efficient cars on the road are around 35% efficient at burning gasoline, electric cars recharging from a gasoline turbine power plant would use less total gasoline for the same energy delivered to the road than burning the gasoline in cars.
Just a little bit of reality: While you I think used "gasoline" as the fuel for utility generation intentionally, of course those are all designed to used methane (i.e. natural gas). Yes, combined cycle plants CAN get over the 60% thermal efficiency level, but what they are HORRIBLE at is high turn down. Once falling off of their ideal design load, they gobble fuel at an alarming rate (think of flying your G7 at treetop level and you get the point).

To me, turbines in low altitude aircraft are very much the parallel to EVs: they CAN give very high performance for a very short time, but the energy storage requirements to allow them any useful range or endurance wipe out their very limited advantages in a hurry. EV's though don't start off with anywhere near the turbine's edge - thus why turbines are used in airplanes, not batteries.
 

bmcj

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Ford, in it's attempt to satisfy new efficiency standards, set up the engine in my F-150 to shut down when the vehicle comes to a stop and then restart when the accelerator is pressed. This can happen over 100 times a day in morning rush hour in traffic. While this undoubtedly helps efficiency, it does not help the starter motor or the engine bearings in any way.
With the typical user-driver maintenance schedules, most cars become more difficult to start as they age, taking more cranking and start attempts. Imagine what that is going to do to urban traffic flow as these cars age.
 

bmcj

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I’m fine with electric cars. Blowtorch battery fires don’t scare me in electric cars, but they would concern me in an electric plane.
 

dog

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sssorry,sssorie! thought this was electric propusion,I'll make a note, dumpster fire 101,
......formerly known as electric propulsion,gotit.
And I have a jug of 50/50 nitro methane and tetra ethyle lead ,totaly yours.
Have a Gretta day.
 

pictsidhe

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With the typical user-driver maintenance schedules, most cars become more difficult to start as they age, taking more cranking and start attempts. Imagine what that is going to do to urban traffic flow as these cars age.
Stop start works just fine in Europe. Why would the USA be different? Those with some weird religious objection to saving fuel and money can always turn it off.
 

bmcj

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We might as well give up on electric vehicles. We can build as many dams and windmills as we want and it still won’t cure the greenhouse gas problem.

https://apple.news/ASlQAWtn1QNeVnyw3AvF_XQ

“Humans put out more methane than previously thought”

On the brighter side of the news (and possibly related)... Taco Bell has opened a record number of restaurants.
 

12notes

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Just a little bit of reality: While you I think used "gasoline" as the fuel for utility generation intentionally, of course those are all designed to used methane (i.e. natural gas). Yes, combined cycle plants CAN get over the 60% thermal efficiency level, but what they are HORRIBLE at is high turn down. Once falling off of their ideal design load, they gobble fuel at an alarming rate (think of flying your G7 at treetop level and you get the point).

To me, turbines in low altitude aircraft are very much the parallel to EVs: they CAN give very high performance for a very short time, but the energy storage requirements to allow them any useful range or endurance wipe out their very limited advantages in a hurry. EV's though don't start off with anywhere near the turbine's edge - thus why turbines are used in airplanes, not batteries.
No, I meant petroleum based fuel, specifically diesel or Jet A. A lot of gas turbine generators can run liquid or gaseous fuel. I know the GE LM6000 is dual fuel but is 41% efficient (design introduced in 1990), and their 9HA (2015-ish) is 64% efficient, I have not seen if the 9HA is dual fuel. There is a high efficiency Mitsubishi I was looking at the other day that was dual fuel, but I don't have time to dig up the model number at the moment.
 

bmcj

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Stop start works just fine in Europe. Why would the USA be different? Those with some weird religious objection to saving fuel and money can always turn it off.
I’m not disparaging the practice, I’m just saying that if the car eventually becomes difficult to start, then it might cause delays.
 

poormansairforce

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We might as well give up on electric vehicles. We can build as many dams and windmills as we want and it still won’t cure the greenhouse gas problem.

https://apple.news/ASlQAWtn1QNeVnyw3AvF_XQ

“Humans put out more methane than previously thought”

On the brighter side of the news (and possibly related)... Taco Bell has opened a record number of restaurants.
Thats funny! Get rid of all Taco Bells!
I've always said they won't be happy until I'm pushing my car but then they'll think it over and want me dead.
 
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