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Old 12-16-2016, 10:11 AM   #131 (permalink)
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Slowmover, thanks for your post and for sharing your viewpoint. You wrote, "From my end one can see the utility of a pickup." I absolutely can see the utility and obviously an EV tow vehicle cannot possibly tow a 9,000 lb trailer that is used a primary residence. Which sounds fantastic.

But some people do live in the 17 ft lightweight trailer I plan to buy. See The Path to Less Stuff

That person is towing it with a Subaru Outback, but as I pointed out earlier it can be readily towed with a Tesla EV https://teslaxcanada.com/

My wife and I have no intention of living in our trailer. We love our house. Our trailer will be a recreational "toy" (and I understand you did not apply that term in a deragtory way .

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Old 12-16-2016, 10:13 AM   #132 (permalink)
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Slowmover wrote "If two weeks for a married couple is a reasonable expectation for a TT while boondocking, then, in a specification-by-specification comparison . . . ?"

My wife and I anticipate 3 to 6 day trips in our trailer. Of course we might go longer. But as I pointed out with the two links in my post just above, there are two examples of people who have traveled with their 17ft lightweight trailer for weeks and months at a time and they love it.
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Old 12-16-2016, 10:32 AM   #133 (permalink)
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Quote:
Originally Posted by evtower View Post
Slowmover wrote "If two weeks for a married couple is a reasonable expectation for a TT while boondocking, then, in a specification-by-specification comparison . . . ?"

My wife and I anticipate 3 to 6 day trips in our trailer. Of course we might go longer. But as I pointed out with the two links in my post just above, there are two examples of people who have traveled with their 17ft lightweight trailer for weeks and months at a time and they love it.
How long in one place? No need to replenish? All needs met without services?

We can find many examples of small rigs used long term. Not to the point

Three to six days in one location? No services. Correct?

And about a 100-150-mile roundtrip.

So, at best, a very short distance weekend trip.
Defines current state of the art for EV+TT. At present

Is this fair?

Thus, an Alto 1743, with 15-gls water capacity at a dead minimum of 1.5-GPS water per person per day = 10-days. Really, a week without bathing.

See where this goes when seen this way?
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2004.0 DODGE Ram QC/LB 2500 2WD/NV-5600 305/555 ISB. 7,940-lb. Stock. 200,000 miles/5000-hrs @ 40-mph average.
1990 35' Silver Streak TT 7,900-lb.
11-cpm solo & 19-cpm towing; 21-mpg average past 54k-miles
Sold: 1983 Silver Streak 3411

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Old 12-16-2016, 12:16 PM   #134 (permalink)
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The smaller trailer is an aero disaster, with flat sides leading to the quick slope of the rear 1/4, it is certainly creating a monstrous pair of twin trailing tornadoes that might as well be drag chutes. The bigger trailer looks about right for good aero design in that it starts the air on a gentle let down without swirling it about.

I always try to point out that we are really driving our vehicles "Through calm air" the air is NOT "blowing over our vehicles". The distinction being that the less we energize the calm air we drive through, then the less energy it takes to move on, that is the real basis for aero efficient design. Leave the air as calm as possible after you pass.
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Old 12-17-2016, 08:35 PM   #135 (permalink)
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Slowmover wrote; "And about a 100-150-mile roundtrip.
So, at best, a very short distance weekend trip.
Defines current state of the art for EV+TT. At present
Is this fair?
Thus, an Alto 1743, with 15-gls water capacity at a dead minimum of 1.5-GPS water per person per day = 10-days. Really, a week without bathing.
See where this goes when seen this way?"

You appear to be assuming that in my case my goal is boondocking for many days if not weeks at a time. I am unclear as to why you assume that. I certainly recognize the boondocking limitations of a trailer with relatively small holding tanks. I can do the math. I might do a few days of boondocking but I also envision staying in campgrounds with services.

Regarding charging my EV, the Tesla Supercharger network is extensive and is expanding rapidly. See https://www.tesla.com/supercharger . In addition, electrical outlets are widely available.

Again, I understand that a turbo diesel TV and a 9,000 lb trailer works best for you. I'm happy that you have such a great situation. I have no interest in owning an ICE vehicle or a large heavy trailer. I prefer an EV and a compact and lightweight trailer to use for short trips to the beautiful mountains and recreational areas that are just a one day drive from my home. I will not be living in my trailer for weeks at a time. I have a wonderful house, mortgage free, at my disposal.
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Old 12-17-2016, 11:34 PM   #136 (permalink)
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Quote:
Originally Posted by evtower
Hmm...and that Metro would be able to tow a Bambi about 10 miles before needing to recharge for half a day.
Hmmm... Four suggestions and you pick the wackest one. Suppose the Metro has the battery pack out of a Kia Soul. They have the highest power density.

Lately, I've been thinking about taking two replacement VW floorpan halves and the T-shaped battery pack from a Chevy Volt and making a replacement Beetle chassis from those parts.

slowmover -- I looked at CheapHeat, but I don't have forced air ducts. Just two oil radiators, one at each end. I knew someone that had restored a motor home when their propane tank shot across the garage like a torpedo and burnt it down; so I'm skeptical about bottled gas.

There is a roof penetration for a 4" chimney by the entry door, and I've been thinking a wood pellet Rocket stove might be nice. They are supercharged so they burn the smoke for more efficiency.

To your appliance list you could add a hand-cranked washing machine and a collapsible 3ft diameter solar oven.

For me boondocking is on the opposite side of relocatable. I have a 500-gallon polypropylene tank in a palletized metal rack. I've been thinking about putting that on a trailer axle, if I find another one like that Dexter that passed through the recyclers.
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Old 12-31-2016, 10:25 AM   #137 (permalink)
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Quote:
Originally Posted by evtower View Post
Slowmover wrote; "And about a 100-150-mile roundtrip.
So, at best, a very short distance weekend trip.
Defines current state of the art for EV+TT. At present
Is this fair?
Thus, an Alto 1743, with 15-gls water capacity at a dead minimum of 1.5-GPS water per person per day = 10-days. Really, a week without bathing.
See where this goes when seen this way?"

You appear to be assuming that in my case my goal is boondocking for many days if not weeks at a time. I am unclear as to why you assume that. I certainly recognize the boondocking limitations of a trailer with relatively small holding tanks. I can do the math. I might do a few days of boondocking but I also envision staying in campgrounds with services.

Regarding charging my EV, the Tesla Supercharger network is extensive and is expanding rapidly. See https://www.tesla.com/supercharger . In addition, electrical outlets are widely available.

Again, I understand that a turbo diesel TV and a 9,000 lb trailer works best for you. I'm happy that you have such a great situation. I have no interest in owning an ICE vehicle or a large heavy trailer. I prefer an EV and a compact and lightweight trailer to use for short trips to the beautiful mountains and recreational areas that are just a one day drive from my home. I will not be living in my trailer for weeks at a time. I have a wonderful house, mortgage free, at my disposal.
The questions are the ones which are not about personal use so much as abstract combined rig analysis. For which I leave out purchase cost (which is years of ownership divided into nights of occupancy; which I favor over accumulated miles). We all know to look at car attributes. MPG and the rest to do with power consumption.

But we (the RV community) don't look at the complementary numbers of a particular RV.

With a travel trailer we are free to change the drivetrain at any moment.

So what, then, are the particular attributes of the travel trailer itself? Is it a good match to a class or classes of automobile (a truck is an auto)? What are it's limitations. Design usage? Engineered lifespan?

"Weight" isn't an attribute" of that trailer line. Not really. It's overshadowed by lack of aerodynamic efficiency, poor onboard capacities, lousy roadgoing manners, and a lifespan so short as to be disposable.

Keep looking.

What you buy is one thing. Your business. But if you came here for thoughts on MPG, then there is a larger picture. Pointing out a narrow versus a wide range or depth of TT capability is at the heart of that discussion.

Nights aboard at a single location without re-supply is the summation for a TT.

A TT low on this score -- AND that has the problems above -- is the equivalent of a gas guzzling underpowered automobile.

The very moment I have to move the rig or make a solo supply run, I've killed MPG.

MPG with RVs almost doesn't exist as a topic. I've tried for a dozen years online in many vehicle specific and RV forums. I'm down to about three, now. And for fifty years before that have always understood it to be pertinent.

The points about my trailer have to do with assumptions made that size kills MPG. That "weight" kills MPG with a TT. Other factors must enter into that discussion first.

Some further perspective: when are reports of a particular vehicles MPG accurate and relevant? Not until the operator has maximum passengers and gear aboard with certified Scale tickets at hand plus vehicle manufacturer specifications. Driving around solo is a stunt. Nearly without meaning. For not until we know the shortcomings of a loaded vehicle can we appraise it.

For that solo automobile the percentage change between driver/empty to fully loaded is as revealing as for the RVer from driver/solo vehicle to the automobile with all family members aboard, full fuel and gear as if vacationing (same for trailer: full propane and fresh water plus gear & supplies).

Vehicle specification. Is all we've covered.

Next is climate. Then terrain. Last is driver motivation, big as it is.

Generally, there are few accurate comparisons available. Possible. The guy from work who otherwise the exact same rig as mine won't be a good comparison to mine if he won't also do some testing.

The greatest gains are with the driver once the above is sorted. But it doesn't get done. So there's no way to isolate the effects. To find out what really works (as RR problems -- mainly mechanical -- themselves aren't ever isolated).

And it isn't difficult, which is the pity.

I really don't care if Joe Bob gets 47-mpg in an EPA 32-mpg car. Not without a lot of the all important context of analysis. It's just noise.

The commuter car owners and others around here with bragging rights are as dishonest as the RV owners in willing analysis.

We chase our tails.
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2004.0 DODGE Ram QC/LB 2500 2WD/NV-5600 305/555 ISB. 7,940-lb. Stock. 200,000 miles/5000-hrs @ 40-mph average.
1990 35' Silver Streak TT 7,900-lb.
11-cpm solo & 19-cpm towing; 21-mpg average past 54k-miles
Sold: 1983 Silver Streak 3411

Last edited by slowmover; 12-31-2016 at 11:00 AM..
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Old 12-31-2016, 11:20 AM   #138 (permalink)
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All of the above is before we get to the tow vehicle. And on EV I am spectacularly ignorant.

But not so with solar electric systems for travel trailers. AM Solar would be my only choice for DIY. A couple of techs I'd trust.

I could see taking an otherwise suitable TT and adding solar to reduce weight, but only if it had met the more important criteria first.

I've no idea whether such could help "fuel" the EV, but if it could, that'd sure as hell change the boondocking equation. Maybe not a lot, so I'm ready to see what's reasonable. Apt.

Fuel for persons and vehicles is at the center of things. Time and distance. Duration.

Vehicle longevity is second tier. But equally important. For both.
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2004.0 DODGE Ram QC/LB 2500 2WD/NV-5600 305/555 ISB. 7,940-lb. Stock. 200,000 miles/5000-hrs @ 40-mph average.
1990 35' Silver Streak TT 7,900-lb.
11-cpm solo & 19-cpm towing; 21-mpg average past 54k-miles
Sold: 1983 Silver Streak 3411

Last edited by slowmover; 12-31-2016 at 11:29 AM..
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Old 12-31-2016, 11:54 AM   #139 (permalink)
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Scale weights are one measure, as said. A basic.

Next "might" be acceleration times. 0-60 in twenty seconds is the current trailer "standard", but 0-60 in 30-seconds is fine.

So the question becomes acceleration rate. With an OBD reader on mine I can use 80% engine load as a maximum. With contributor "skyking" we will be able to factor out:

1) Vehicle spec
2) Climate

and hopefully

3) terrain, as altitude is easy to factor. We both just need a level test road.

For a MPG test Loop of sufficient distance, one acceleration run from a dead stop and maybe a rolling highway entry at the turnaround point. A cruise control setting of a speed which requires no lane changes on an Interstate. And a return to the same fuel pump at the same station.

Our vehicles are not exactly alike. Our trailers are of a different design class.

Besides engine load percent, average mph can be recorded, and exhaust gas temps noted.

Our vehicles have had (or will have) mechanical rolling resistance issues verified. Even if the four different vehicles are not yet in final configuration.

As opposed to the same route run under the same conditions (truck solo wright sane in each) we're always looking for the percentage MPG change from solo to towing having eliminated all but "driver motivation" (most of which is negated by use of cruise control).

I'm certain a similar kind of regimen would work for EVs.

The point is not competition, but co-operation.

For more than 90% of ICE tow vehicle/TTs conventionally-hitched we're going to find hitch adjustment problems. That's after all the other potential problems on otherwise near-identical rigs.

So if it turns out skyking and I could make a comparison test -- and were down to comparing engine run data -- it's only AFTER the RR issues are done.

Which won't be the case with Teslas and TTs. Homework and pop quizzes precede the semester exam.
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2004.0 DODGE Ram QC/LB 2500 2WD/NV-5600 305/555 ISB. 7,940-lb. Stock. 200,000 miles/5000-hrs @ 40-mph average.
1990 35' Silver Streak TT 7,900-lb.
11-cpm solo & 19-cpm towing; 21-mpg average past 54k-miles
Sold: 1983 Silver Streak 3411
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Old 12-31-2016, 08:08 PM   #140 (permalink)
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Not to take away from all that you wrote, but a 35ft park model trailer on county tax rolls is the perfect 'tiny house'.

Or, so my confirmation bias says.

Have a Happy New Year.

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