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shelbyfv
TN
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Joined: 02/18/2006
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![[emoticon]](http://www.rv.net/sharedcontent/cfb/images/doh.gif "doh") Apples and bananas too complex,eh? Going circular here with the double down, I'm out.
* This post was
edited 07/07/22 09:03pm by shelbyfv *
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tommyznr
NR, WI
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shelbyfv wrote: Apples and bananas too complex,eh? Going circular here with the double down, I'm out.
Call it apples and bananas if you like. Look at it like you need to eat x amount of apples vs y amount of bananas to get enough calories to go on a 10 mile hike with a 40 pound backpack.
Maybe his statements are inconsistent with the math and units but his overall point is valid. The way I read it.........With the current state of the technologies you need x storage of diesel vs y storage of Li to tow a typical setup 300 miles. He does not point this out as an absolute as the apple/banana analogy would be because that is not the point he is trying to make.
This is the problem I have with engineers on a daily basis. Many of us see a problem in the context and cannot ignore the problem and get the larger point.
I hope I captured your point Turtle without stepping on your toes.
Tom
2017 GMC Sierra SLT, Max Tow package
2018 Grand Design Reflection 295RL
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propchef
NORCAL
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Turtle n Peeps wrote:shelbyfv wrote:Turtle n Peeps wrote:shelbyfv wrote:What are you towing with currently?
3/4 ton Dmax. Has anyone prohibited you from driving it or buying fuel? Didn't think so. You seem to be the only one on the forum who is worried that someone will take your truck away and make you tow with an EV. Propchef has owned you on this one, btw.
Where did I ever say anyone is going to prohibit me from driving my truck? Go on, quote me. Didn't think so.
BTW Propchef didn't own anybody. The Lightning had an energy density problem and I pointed that out. He dose not seem to understand this. I don't think he even understands the term? I tried my best to explain this but he does not seem to understand. Then I gave him a video with an engineer that tried to explain the problem in the simplest terms. He still does not grasp it. No problem.
Most of the people that don't understand and more than likely don't even own an electric vehicle....much like Propchef.
Like I said above; this is a RV towing forum. For me the five most important things when tow an RV are #1. horse power #2. stopping power, #3. range #4. cost/mile and #5. capability to control RV in back of me.
If anyone of the above are missing you're going to have a very bad experience. The Lightning did great on all of the above except #3. That darn #3 keeps on getting in the way of towing things with a battery powered vehicle. LI batteries just don't have the energy density and more than likely never will. Will some other battery come out and solve this problem? Maybe, maybe not.
I posted the definitions, and I understand them well. You've made a decision to ignore those definitions and insert your own based on a random YouTube video.
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propchef
NORCAL
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RoyJ wrote:propchef wrote:Again, fuel burns (releasing energy), and lithium is part of a storage system. Apples to bananas. Lithium is rechargeable. Diesel isn't.
Your example doesn't make logical sense.
Not sure if I follow what you're saying.
When comparing batteries to liquid fuel, the only meaningful comparison is energy density.
The power density of liquid fuel is virtually unlimited. Example, you have big enough fuel injectors and oxygen (top fuel dragster), you can output 8000 hp from a 10 gallon tank.
Not for long of course, but now we're talking about energy...
There are several "meaningful comparisons" to make with batteries besides what is being called "energy density." How much of a charge can the battery hold (capacity) and charge/discharge rates are also properties of the battery that are difficult if not impossible to compare to liquid fuel. Power delivery (discharge rate) is far greater with modern batteries than with burning liquid diesel fuel. That's the massive torque hit you get when you punch the accelerator in an EV from a standstill. Diesel can't do that.
I've mentioned several times now and have not seen a response to the fact that the gallon of diesel burns and is gone, but the battery can be recharged over and over.
Comparing liquid fuel to an electric storage system cannot be done accurately using only one metric.
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tommyznr
NR, WI
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"I've mentioned several times now and have not seen a response to the fact that the gallon of diesel burns and is gone, but the battery can be recharged over and over."
Sure, and maybe I am missing something here, but what does that matter to the person who has to either fill his tank with diesel or plug in his battery to charge it to go 300 miles?
After all, a depleted battery is conceptually the same as an empty tank.
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valhalla360
No paticular place.
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Joined: 08/19/2009
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shelbyfv wrote:It's probably true that there are some clueless simpletons in the RV community, same as anywhere. Thankfully, folks who make a living developing high tech didn't get there with low brain power. Most of us couldn't get through second year college math, much less engineering school or an advanced degree in any science. I'm optimistic because I know smarter people are out there working on solutions. Less so when I ponder if the rest of us will have the judgement to accept them.
Unfortunately, the marketing and eco-warriors are dominating the EV promotion, not the engineers.
When you get people who do understand the math discussing it, EVs have a limited use case. Commuter cars, sure. Short range, light cargo delivery trucks, sure. School busses that go back to a yard to be recharged for several hours twice a day, sure.
When they go up against the longer range capabilities of ICE, it's not even close and no big technological change is on the horizon.
Of course, those limited use cases are not inconsequential. Probably 25-40% of personal vehicles could be changed over. Lots of families with multiple cars and a garage to charge them overnight in. With multiple cars in the family, keeping a long range ICE and a commuter EV is very much viable...just not particularly relevant to RVing.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV
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valhalla360
No paticular place.
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shelbyfv wrote:Part way there with a Prius. Won't tow my trailer, though. ![[emoticon]](http://www.rv.net/sharedcontent/cfb/images/wink.gif "wink") Clearly there is more incentive to move on than there was 70 years ago. FWIW, we were OK with leaded gas back then!
They were also calling on us to run out of oil in 20-25yrs back in the 70's, yet proven reserves have actually increased over the same time period.
Not that we shouldn't be improving our efficiency and use patterns but there really isn't much difference.
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valhalla360
No paticular place.
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propchef wrote:I do not understand that graphic at all. What exactly do you mean by "energy density" or are you referring to "power density"?
Diesel burns to create heat which is used for power. Lithium is used as a material in a storage system for electricity (battery) and does not generate any power of its own. Why don't you compare the energy density of diesel to say, lead? Or sulfuric acid?
And batteries can be recharged. Can't do that with liquid fuel.
I suggest taking a physics class that covers the difference between energy and power.
EVs win on power density. Of course, that has nothing to do with the battery bank. One measure of that would be HP/lb of motor. A 200HP electric motor is going to be significantly lighter than an equivalent HP ICE, so the electric motor has greater power density.
Energy Density relates to how much energy can be stored. Kilowatt Hour (KWH) is one common measurement of Energy. An 80 KWH tesla battery weighs around 1200lb. That translates to an energy density of round 133 KWH/ton.
Diesel is a bit under 12,000 KWH/ton.
Now, EVs use those KWH more efficiently but even accounting for that, it's not even close in terms of how much Energy you can store and that's the crux of long range heavy towing. An 80k lb truck trying to do 500miles/day is going to need a battery that weighs several tons because energy density of batteries is too low.
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Thermoguy
Graham, WA
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Here is another video with someone towing an Airstream trailer with the Lightning. Looks like about 100 miles towing available, but they only drove about 5-10 miles so not a good "real world" test for distance, but a good review of everything else. They are good to point out that an RV user needs to go 300 miles with a charge for a EV to be viable to a RV user.
https://www.youtube.com/watch?v=3FmUcVHEJME
Basically, as pointed out in this tread, the issue is battery capacity and range anxiety with regards to towing.
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Lwiddis
Southern California :(
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An Airstream that mostly powers itself?
Winnebago 2101DS TT & 2022 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AH Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad
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