[slowmover]

evtower, I do appreciate the perspective. A new world for me.

To add perspective from my end -- not in rebuttal, I caution -- is the practicality of travel trailer use. Consider this long post as distillation from a lot of beer-drinking around the campfire. This really isn't going offtopic as far as it may first seem:

The number one attribute of an indefinite lifespan travel trailer [TT] is to be able to change the tow vehicle [TV] over that ownership lifespan. With my size of travel trailer (35' at 9000-lbs gross; more likely at 8,000-lbs plus) one can travel with a family of six in, say, a full sized van until the kids are grown and then transition to something which makes more sense for a couple. Who are eventually on a retirement fixed income with capital expenses in the past. It's an interchangeable part, on the one hand, but expecting 15-years of service at low overal cpm isn't unreasonable. (This ends TV discussion).

The best known group for those full-timing in RVs is Escapees, out of Livingston, TX. Have sold the stick & brick house and roam the continent pretty much at will (though it's a given that RV use is about chasing shirt sleeve weather). Domicile in a low tax state. Possibly a members-only property in an SKP or other (Airstream-only) park. Usually retirees. Then the category of those still in the workforce. All over the country, some on years-long capital improvement projects (refineries, power plants, etc), the rest of us as career would have it.

In both cases the practicality of the TT is paramount. Eclipses all other considerations. Sick and laid up? This is where one will be. Long spell of bad weather? Again, this will be the square footage to trod.

Thus,

Can I operate the TT on propane only (the local area has lost electricity for an unspecified period)? The TT appliances in no order are AC, refrigerator/freezer, range/oven + microwave/convection + portable induction unit; water heater, and furnace.

AC: electric only. 30A power per single unit, 50A service for two. Requires generator of preferably 4000W or greater. Problem now is genset and liquid fuel storage if not propane powered (which has its own safe-handling problems).

Reefer: 3-way; propane, 12V or 120V.

To cook (as above); propane or 120V, with a only a couple of 12V cookers available. Coleman Stove needed. Problem of liquid fuel storage

Water heater: propane or 120V. Otherwise, water heated on Coleman Stove.

TT heat (not just comfort, but heat to water-storage tanks; this is crucial): Propane, 120V (freebeard, see rvcomfortsystems.com; CheapHeat). Without 120V or propane aboard, this is trip-ending. (Yes, a Webasto or Espar diesel-fired heater could be installed, but without an integral weight-problematic fuel tank retrofit, it's a near dead-end).

With a turbodiesel truck one can fit the sort of generator that runs off the engine, thus eliminating a separate piece of equipment. Or, a big propane generator can be fitted to the TT to charge house batteries, run AC a couple of hours per day (thus the limitation on being parked in a hot weather location), and run other appliances as needed for a specified period of use (all to limit liquid fuels safety).

(Generator discussion can go beyond this, I'm looking to make integral what is necessary to not have to abandon ship at a locale). I've also left out two-way radio requirements (HAM transceivers).

The other appliances I'm considering are not usually thought of as being energy conscious, especially for an RV, but -- taken to mean no use of the TV -- they are: a dishwasher and an clothes washer/dryer (where one converts clothing, bedding, towels, etc, to artificial fabrics). With optional 65-gl fresh water, even an electric-only campsite is not limiting. And these are or can be built-in. I'd like an ice maker also. If I have to leave a campsite to replenish before I run out if water, I've lost "utility".

Haven't discussed water, but the ability to filter water for health is fundamental. The day may come it is crucial.

How long can one stay in a specified location, as fresh water storage is the central limitation? is, to my way of seeing things, the single most important question about an RV. Otherwise one owns a toy. Nothing wrong with a toy, per se, but let's include all needed inputs of energy. Shelter, water, food. Not having to fire up the TV and go to town.

From my end one can see the utility of a pickup. I carry about 1,300-lbs of gear in the truck constantly. In the above one can see the need for extra gear for any TT owner looking to "boondock" (camp without services) for extended periods.

Thus, prior to saying one is "free to travel", the statement implied in "free" has to be amended to include weather and time limitations. Especially on a forum where energy consciousness is high. This is not a criticism. It's hardly a staple topic among RVers in general. If anything, the general assumption is that all is rosy and will remain so. (One doesn't have to search hard to find stories of equipment abandoned in face of hardship).

EV + TT = how long independent of outside inputs?

It's easy for me to say that I can make a 600+ round trip at average MPG (with planned fuel tank upgrade) given gentle terrain and with two-weeks plus at a single-location without refueling. I'd consider less than a 500-mile range to be a problem. As much as a month in place can be done. No genuine hardship for lack
of utilities. (This is the advantage of a TT 28'-34'; water and propane capacity and fewer weight penalties).

A given choice of TV can be limiting for several important reasons (and a host of minor ones). In the above I think one can see the utility of a hybrid drivetrain ( ability to charge TV and TT batteries with potential to do more as a genset) Etc. In the meantime turbodiesel is king. This, I think, is the direction from which to consider EV & RV. A "rigorous" standard. I haven't covered all, but

The choices of TT specification define all other limits.

Is the offering, here.

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