Propane Generator Option For Longer Trips

[CyberKev]

Check out this cool video from Cybertruck Guy on Youtube. Creative option to extend those off-road trips to distances you didn't know could be possible. Like his channel!

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[Gh0stHack3r]

CYBRTRK will come with built-in solarchargeing as option, no need for old fossil crap....

 

[ajdelange]

.9*7000/450 = 14 so yes, you could charge a CT at 14 miles per hour from a 7 kW generator and 400 gal of petrol only weighs 2400 lbs. Interesting white board exercise but in reality? I guess the first thing that occurs to us is that whilst one might get 450 Wh/mi consumption driving into the park once you get off road it is going to go up - potentially dramatically depending on the substrate. Another potential big factor would, of course, be going up and down hills.

 

[CyberKev]

CYBRTRK will come with built-in solarchargeing as option, no need for old fossil crap....

The solar tonneau cover will charge up to 14 miles per DAY, maybe a little more. The generator option would be around 14 miles per HOUR. BIg difference there as far as the time it would take you to get yourself out of the woods safely. And of course the other 98% of the CT's use, not being off-roading, wouldn't need any propane. So we're still DRAMATICALLY decreasing the amount of fuel being used in a trucks' lifetime. But maybe a little extra help for long trips. Still, a 300 or 500-mile range off-roading is a LOT OF OFF-ROADING.

 

[ajdelange]

Probably more like 7 - 10 miles per hour with the generator because of higher consumption off the bitumen and with the solar panels 7 miles per day in the desert at the summer solstice. Probably half that in a mesic zone near the winter solstice.

Also take note that the added load of the generator and all the jerry cans full of gas requires more Wh/mi.

It's interesting (again as a white board excercise) to contemplate the situation of one poster here who wants to pick up his CT in CONUS and drive it to Alaska. There are evidently long runs with no charging opportunities. Suppose he drove 400 miles, camped and recharged. Assuming that he can indeed recharge at CT at 24 mi/h from a 7 kW generator it would take 400/14 = 28 hrs to replace 400 miles. Doable but....

 

[CyberKev]

Probably more like 7 - 10 miles per hour with the generator because of higher consumption off the bitumen and with the solar panels 7 miles per day in the desert at the summer solstice. Probably half that in a mesic zone near the winter solstice.

20 Amps and 4900 watts is 14 miles per hour of charging. Here's the source:

 

[ajdelange]

20 Amps and 4900 watts is 14 miles per hour of charging. Here's the source:

20 A from a 240 V generator is 4800 watts which would give me .9*4800/280 = 15.4 miles per hour in my X but with a CT only .9*4800/450 = 9.6 if, and this is a big if, I could realize 450 Wh/mi. When you get off a prepared substrate and when going up and down rugged terrain consumption goes way up. So probably more like 5 - 7 miles per hour for a CT if off road.

But I assumed a 7 kW generator which would deliver .9*7000/450 = 14 mi/h @ 450 Wh/mi as I said in an earlier post . Probably 7 - 10 off road.

What I hope you will learn from this is that the miles realized by adding a certain number of kWh to a battery depend on a number of factors such as which vehicle is under consideration, the conditions under which it is to be driven and the driving habits of the operator. One cannot, therefore, simply declare that 4900 Watts is 14 miles per hour. Note that your boys in the video experimented with an X but the X I drive would give me 15.4 (how, as and where I drive it) from 4800 W.

The other very important aspect of this is that a number like the 15.4 I quoted is an average based on my average consumption. Within a season actual consumption can vary quite a bit and the seasonal averages are not the same in winter as in summer.

 

[lancethibault]

.9*7000/450 = 14 so yes, you could charge a CT at 14 miles per hour from a 7 kW generator and 400 gal of petrol only weighs 2400 lbs. Interesting white board exercise but in reality? I guess the first thing that occurs to us is that whilst one might get 450 Wh/mi consumption driving into the park once you get off road it is going to go up - potentially dramatically depending on the substrate. Another potential big factor would, of course, be going up and down hills.

Either he's very wrong, or you're very wrong, or I'm reading what your wrote very wrong and I'm just looking to clarify.

The video made the case for 192 miles of extra range with four 4 gallon propane tanks at a cost of $80 (just for those 4 tanks). This was based on the assumption that every hr on the generator will create 12 miles of range. The assumption of 12 miles was based on the other video of the model X getting 14 miles for every hr on the generator.

Based on your later posts I know you said 7 - 10 miles of off road use for every hr of charge. That makes it more like 112 - 160 miles of range for those four propane tanks. Is that correct?

 

[Geo]

Either he's very wrong, or you're very wrong, or I'm reading what your wrote very wrong and I'm just looking to clarify.

Lets give Aj the benefit of the doubt and just say he's getting a little confused !

The give-away is , he knows for a fact that you can only charge up while vehicle is stationary, so mentions that relate to consumption of energy, wh/mile, and conditions, going up and down hills, and driver behaviour are all absolutely irrelevant.

Also the baseline consumption of the Cybertruck is yet to be confirmed, but there's reason to believe that it may fairly similar to the Model X. So less than the 300 wh/mile, rather than the 450 Wh/mile mentioned. Although he's quite correct that while driving off road that figure will be severely impacted.

P.S The TFL guys did charge at 20 Amps but all the way up to 32 is possible. And you don't need to use a 7000 watt Generator, 9000 or more is feasible and size is comparable.
Its definitely possible to charge up at over 20 miles of charge per hour using a mobile generator.

 

[CyberKev]

Do all of you really think off-roading will drastically diminish the range? Tesla semi can do incredible things and go great distances while considering mountain passes. Is the CTs range accounting for highway mileage, agains wind resistance? I don’t think it’ll actually deplete that much battery juice just by going like 8 mph over some rocks. We also don’t know what off road modes will do as far as how the technology will conserve battery life and provide incredible torque. I think the tech and the truck will be able to get close to 300 miles (dual) of pure off road. It won’t be that the truck will get 300 miles of range on highway but only 150 off road, right?

 

[CyberKev]

I think the most optimistic point here we can make is that battery day is coming up in September and if Tesla is going to compete with Hummer EV, Rivian, and Fords E Truck, I think we will see impressive improvements in the ranges that were released in the CT unveil.

 

[ajdelange]

There certainly does seem to be some confusion here and while I am, admittedly at this point, confused as to what the confusion actually stems from I am going to guess that it stems from some peoples' belief that a certain power level laden into the vehicle for a certain time corresponds to a fixed number of miles on the road. I draw that conclusion from statements like these:

20 Amps and 4900 watts is 14 miles per hour of charging. Here's the source:

The give-away is , he knows for a fact that you can only charge up while vehicle is stationary, so mentions that relate to consumption of energy, wh/mile, and conditions, going up and down hills, and driver behaviour are all absolutely irrelevant.

With respect to the second: I do not know that conditions are irrelevant. They absolutely are.

I think Tesla (and other manufacturers) do us a disservice when then present information to us about the rate at which miles are being added during a charge and when they allow us to set our battery indicator to indicate miles. You do not know how far a gallon of petrol will carry you when you fill your ICE vehicle and you do not know how far a kWh of electric energy will carry you when you charge your BEV. If you have been using your odometers and TeslaFi you may have some idea as to how far it will take you based on your driving history. In fact, you may have even accumulated data on how far it takes you on average in off road conditions. But the numbers on the battery gauge and charging displays are 'rated' miles based on rated Wh/mi numbers. Those with technical backgrounds generally tend to set our battery displays to % very soon after acquiring a Tesla and nearly always tend to advise others to do that too. But the pushback from non techical people is often huge. An engineer with a 50% SoC charge reading can instantly turn that into an estimate of his remaining range given his current driving conditions but a retired professor of Italian Renaissance Literature cannot.

I think we can all agree that 7 kW applied to the charger for 1 hour delivers 7 kWh to the vehicle. How far will that carry us? There is no way to know because we do not know, exactly, how we will be driving when we consume that charge. We do have a rough idea though and can obtain an estimate from our knowledge of how the vehicle behaves under various conditions. For example, ABRP seems to think that a CT is going to need 500 Wh/mi. If you think they are right you calculate 0.9*7000/500 =12.6 miles (the 0.9 represents the approximately 90% efficiency of the Tesla charger). But you must understand that is the mileage you would get only if your consumption is actually 500 Wh/mi and the charger is actually 90% efficient. Differences from those parameters will result in a different number of miles delivered. If you prefer to believe that the CT will consume more like the current X (unlikely IMO because of weight, CD and frontal area) and that the charger will be 91% efficient then calculate 0.91*7000/300 = 21.2333 miles. But, when you are driving off road you aren't going to get EPA consumption. If driving on wet pavement increases consumption by 25 - 30% what do you suppose driving through sand at the beach will do? Or crawling up a gullied, log laden track (the motors are less efficient at slow speed)?

Its definitely possible to charge up at over 20 miles of charge per hour using a mobile generator.

Here's another quote that reinforces my thesis about the root of folks' confusion. Does the writer understand that it may be possible but only under certain driving conditions? Let's suppose he has a generator capable of 11.52 kW - the maximum the truck will take. Simple math shows that, with 90% charging efficiency, more than 20 miles per hour is being added only if the driving to follow will consume, on average, less that 518.4 Wh/mi. So is this possible on the bitumen? Quite probably. Is it possible in sand? Probably not. Here we are supposing that the CT does not have the second charging port that we love to speculate about or that if it does our man does not have a second generator.

Do all of you really think off-roading will drastically diminish the range?

There really isn't any question about that.

Is the CTs range accounting for highway mileage, agains wind resistance?

The 500 mile range number is Tesla's estimate (and you can be sure that they will meet or slightly exceed it) of the EPA range. It is based on a prescribed profile of speed and time intended to represent a mix driving in urban and highway environments. Drag is included.

I don’t think it’ll actually deplete that much battery juice just by going like 8 mph over some rocks. We also don’t know what off road modes will do as far as how the technology will conserve battery life and provide incredible torque. I think the tech and the truck will be able to get close to 300 miles (dual) of pure off road. It won’t be that the truck will get 300 miles of range on highway but only 150 off road, right?

These comments indicate that your understanding of vehicle dynamics, regeneration, electric motor characteristics etc. has got a way to go. It will be 300 miles on the road and 150 off or something like depending on conditions off. This is the most important concept you need to grasp to understand all this.

I think the most optimistic point here we can make is that battery day is coming up in September and if Tesla is going to compete with Hummer EV, Rivian, and Fords E Truck, I think we will see impressive improvements in the ranges that were released in the CT unveil.

No one can be sure, of course, but it would seem pretty evident that what we will hear on Sept 22 is already "priced in" as they say of the stock markets. IOW at the time when the CT was revealed Elon and his buddies knew what was going on in the labs and whether it would be available at the time production of the CT starts. Anything is possible, of course, but should Telsa have a battery with 20% more energy density than they thought they would have and that costs 20% less to make they probably won't announce that the range of the Tri is now 600 miles. They will probably just use 20% fewer of those batteries and keep the profit. Even so range would go up a little because of reduced weight.

 

[lancethibault]

ajdelange....but do you believe a person could reasonably expect 112 - 160 miles of additional range with four 4 gallon propane tanks and generator? My confusion comes from your statement of needing 400 gallons of petrol and I'm just trying to figure out what you meant by that.

 

[ajdelange]

Ah, I see. No, I didn't actually say that you would need 400 gal of petrol though it is easy to see why you might have thought I was implying that. Sorry. Bad wording. In fact I was poinitng out that 400 gal of petrol weighs 2400 lbs implying that you could easily carry that much and a generator within the load limits of a CT. A 7500 kW generator typically burns 3/4 gal per hour so that you could, with 400 gallons, run the generator for 533 hours delivering 4000 kWh implying that a 2400 lb load of gasoline is good for something like 8000 miles if you can arrange the 533 hours to collect them. I'd have to work out the equivalent for propane but the gasoline result certainly suggests that one could easily carry enough of it (liquid propane) to get you back home. They are both alkanes, after all, and the energy densities can't be that dramatically different.

[Edit]I checked. Gasoline is 47.3 MJ/kg and propane 50.3 so yes, the specific energies are very close.

 

[CyberKev]

Great insights and you guys are very good at math, I will give you that! So good at math that I have a new challenge for you. So here's my challenge to you, should you choose to accept: What is your best educated guess of the battery depletion of a Dual Motor CT, that will go a distance of 20 miles of moderate off-roading, with an elevation gain of 2,660 feet? So 10 miles up (to reach 2,660 ft) and 10 miles back down. Go! (This is based off of one of my local trails called Stony Pass in Silverton, CO) From these details, I will be able to put into perspective the CT's off-roading capabilities in some realistic environments. From here, we can maybe calculate what a full day of off-roading would look like and see at what point would we might consider carrying a generator and some propane tanks in a real-life situation