how dangerous to store propane tank in trunk?

Well, that is another issue entirely. If your to stupid to shut a valve off,... welp.
Also, if there isnt a valve, or way to get at it,.. then what do you do? Also, acetelyne isnt "expolosive", .. it wants oxygen. Like others. And it will do more of a "poof" than nuke the place. Ask any welder what they do to the new guy. (fill bag of acetelyne, and let it rip for a POP" in the shop. That said,..... to me,.. carrying fuel in my rig, like say gas, propane, what not, you know, to go camp, doesn not make a atom bomb on the road. But again, to each their own. (no sure how else you go anywhere, wondering about such things)

EDIT- and dude,.. those tanks are built, engineered, beyond belief. But sure,.. like a pop can, i guess there are some, that cant operate a pop can.

 

You state you're here to learn, and then give from what I'm interpreting as discrediting my opinion based on verbiage like, "you do you mate" which in common language exchange means "I do not agree with your point." You asked for my opinion. I provided. You tell me I'm wrong? Ok weird tactic.

Two points from me, since you are "here to learn" but obviously maintain a hostile and "know it all attitude" using anecdotal evidence.

First, not a single HAZMAT manual will have you move or transport flammable materials within a container not designed for that, i.e. the inside of a 4Runner.

Secondly, acetylene is highly flammable. Acetylene within an enclosed area will explode.

Everyone else. Do not listen to this man. He will get you exploded.

https://youtu.be/N-Qp2Lvrliw

 

C’mon man! Dont exagerate! That van didnt “explode”! There was barely any fire. In reality, all it did was poof, and it barely lasted a split second.

My point was, that user error is part of the overall risk. I, in fact, have done stupid things at times. No sympathy requested. But knowing my own capacity for error helps me manage risk in all sorts of things in life. Usually, doing one stupid thing at a time doesn’t kill a person. But once you combine two stupid things, your risks go up significantly. Three stupid things together usually wins a stupid prize.

Storing tanks inside enclosed vehicles is apparently considered legally stupid in a lot of places. If you decide to do it anyway, and then you add a stupid user error…like you said…welp!

 

I ordered a one burner Dux induction cooktop that arrived yesterday (about $150). I can use it in the house and plug it into my Jackery to cook and learn the right settings and how much it drains the Jackery; from what I've read cooking a couple of meals a day might take 20% of its capacity, which I can easily manage because my 4Runner will rarely stay put for more than a day or two when I'm on the road. I can recharge the Jackery via the 400 volt plug in the back. The Jackery 1000 Pro will recharge from 0 to 100% on an AC outlet in a couple of hours, maybe a little longer if it's being used as a pass through while it's powering a portable refrigerator. If I ever decide to hang out in one place longer and leave the 4Runner parked, I can add solar panels to recharge the Jackery.

I can't use the induction cooktop at the highest settings without exceeding a 1000 watt draw, which is the most the Jackery 1000 Pro will power on a sustained basis according to the specs. It is rated to handle up to 2000 watts on a temporary spike and the Dux maxes out at 1800 watts at full power, but I'll stay away from the higher settings. The power demand induction cooking creates is why I only got a one burner cooktop instead of two. From what I've read and seen in videos, I can cook just about anything by staying at settings that use under 1000 watts.

Between the Jackery 1000 Pro, an Iceco 45VL portable refrigerator and the Duxtop cooktop, I'll not only be set up for food storage and cooking while camping out of the 4Runner, I can use them in my kitchen at home to be able to cook a meal and preserve refrigerated food during power outages. Using induction cooktops instead of cooking with propane for camping/overlanding seems very common in Australia, less so in North America. Probably 80%+ of the videos I've seen on it are from Aussies.

 

I've got way too many things on my mind when I'm traveling to trust myself to do everything right all the time. Not carrying a propane tank around in or on my vehicle is one less thing to have to think about. I can easily be that stupid user if I'm a little bit distracted or in a hurry.

 

Acetylene and propane are very different. The reason acetylene tanks are so heavy is that the steel tank is fully filled with a cement like material that acts like a sponge to hold liquid acetone. The acetylene is dissolved into this acetone. Similar concept to sticks of dynamite are filled with a sawdust like filler that nitroglycerin is soaked into.
Reason : acetylene gas is very unstable (kaboom) as is liquid nitroglycerin.
Propane, butane, map gas, etc are flammable gases that liquify at relatively low pressures so their thin steel tanks usually have some liquid in them that you can feel sloshing around till they are empty.
Even small backpacker & camper size propane cylinders should be kept ventilated areas.