Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-01-2017, 09:27 AM   #41
3 Rivet Member
 
2017 22' Sport
North Bay , California
Join Date: Nov 2016
Posts: 224
Images: 11
Quote:
Originally Posted by Nuvite-F View Post
Let's run some numbers. The original poster says his Tesla X has a usable battery capacity of 84 kilowatt hours (kWh)
Thanks, Nuvite-F. Your math is valid with a few caveats (which go in both directions). First, an EV is unlikely to show up with no charge, so that 84kWh number is unlikely to be fulfilled from a state-of-charge perspective. However, there's also approximately 8-10% in losses from the charging activity (AC/DC conversion and resistive losses). This varies based on the amperage being drawn by the vehicle. That must be added to the electricity drawn by the vehicle irrespective of state of charge (SOC).

Note that the Tesla allows you to "dial down" your draw to whatever level seems appropriate, so in a situation where I'm sharing a breaker at an RV site, I'm likely to spin it down to 20A or lower. Higher amperage charging is generally more efficient, but not by much.

Funny thing is that these probably wash in a lot of cases. I'll likely show up needing about 75kWh for a charge, which will actually draw 75+7.5=82.5kWh.. pretty close to your original number!

As far as cost of electricity, it varies as you mention. I don't know what commercial rates look like, but I do know they're confusingly higher than residential rates. I wouldn't be surprised if some of the RV parks have to pay 25c/kWh and higher (realizing that some likely pay less than 10c/kWh as well). At 25c/kWh, my hypothetical charge above would cost the park $20.63. That's a charge that I'd be happy to pay outside of my camping fees. I know at least a few RV parks do this already, and for Teslas that stop at RV parks to charge without a trailer, they almost always charge $5-$20 to charge.

To the broader question by McDave of whether or not parks would start metering, it's possibly a good idea in general. As it sits now, there's no incentive to minimize energy waste (other than personal). Those who use the least subsidize those who use the most at the park through average camping rates. If the park could decouple the electricity cost from the camping cost, it would create good incentives for keeping AC off when not inside, etc. I'm guessing my opinion on that is not terribly popular, though.
__________________

ohmman is offline   Reply With Quote
Old 01-01-2017, 11:34 AM   #42
Rivet Master
 
McDave's Avatar
 
2014 23' Flying Cloud
Fair Oaks , California
Join Date: Feb 2014
Posts: 717
Towing with Electricity and a Model X

Quote:
Originally Posted by ohmman View Post


To the broader question by McDave of whether or not parks would start metering, it's possibly a good idea in general. As it sits now, there's no incentive to minimize energy waste (other than personal). Those who use the least subsidize those who use the most at the park through average camping rates. If the park could decouple the electricity cost from the camping cost, it would create good incentives for keeping AC off when not inside, etc. I'm guessing my opinion on that is not terribly popular, though.

Probably impractical and uneconomical to have separate meters installed by the power company, as this would vastly complicate billing and significantly increase cost over the amount the utility charges for the park as a whole. However, I would imagine there are meters one could buy and install privately on each site. The problem then becomes one of how to charge for use, and recover the cost of the meters. Unless the whole thing could be automated such that a clerk in the office could look at a computer screen that would show how much to add to your bill, collecting the usage and calculating the charge would be cumbersome. And of course would mean that everyone leaving the park would have to stop by the office to pay on their way out.

However, the problem is real, as $10-$20 extra cost on a $40-60 site is a significant extra cost for the park. I would imagine they would solve it by adding on a surcharge for electric vehicles, assuming that everyone towing with an electric vehicle is going to need some amount of recharging, and it is, after all, convenient to be able to recharge your electric vehicle at the same time you're powering your trailer.
__________________

McDave is offline   Reply With Quote
Old 01-01-2017, 11:42 AM   #43
Rivet Master
 
Southwestern , Ohio
Join Date: Nov 2006
Posts: 1,669
For what it's worth, in my experience (15 years of Airstreaming), many parks that have significant numbers of seasonal occupants already have individual meters at the pedestal. They typically don't charge separately for electricity when renting at daily rates, but they do for people paying longer-term rates, which are typically significantly lower per day.

I really don't see any problem in the near future as I don't expect to see very many electric tow vehicles for at least the next several years.
Nuvite-F is offline   Reply With Quote
Old 01-01-2017, 03:14 PM   #44
Stay CazuaL
 
cazual6's Avatar
 
2018 25' Flying Cloud
2014 19' Flying Cloud
Reseda , California
Join Date: Aug 2014
Posts: 792
Images: 1
OP, How does your range get affected on inclines? Drastic or reasonable?
__________________
"No job is so simple that it cannot be done wrong."
"Everyone is entitled to be stupid, but some abuse the privilege."
"Either I will find a way, or I will make one."
WBCCI 9164
https://www.facebook.com/groups/2284022111820203/
cazual6 is offline   Reply With Quote
Old 01-01-2017, 04:02 PM   #45
3 Rivet Member
 
2017 22' Sport
North Bay , California
Join Date: Nov 2016
Posts: 224
Images: 11
Quote:
Originally Posted by cazual6 View Post
OP, How does your range get affected on inclines? Drastic or reasonable?
If the incline doesn't include any descents - that is, if the elevation change between charging station 1 and charging station 2 is a vast positive, it is a pretty drastic effect. Currently I'm using data submitted by another Tesla owner with a 22' Sport, but I ran these calculations to see if I could crest Donner Pass en route east from coastal California. We saw that he appeared to use an additional 5.24Wh/ft of elevation when climbing over his average.

Supercharger Rocklin at 318 feet. Donner Pass at approximated 7209 feet. [5240Wh/1000ft elevation * (7209 - 318) elevation gain] + [575Wh/mi * 68.3 miles to the peak] = 75381Wh. From that point, it's all regen for the remaining 9 miles to the Truckee Supercharger.

So from pencil and paper calculations, it appears I could go from a full charge in Rocklin, CA to Truckee, California in ideal conditions. That's only 77 miles! On the bright side, my return wouldn't require charging at all because I'd have a full charge at the bottom of the hill due to regenerative braking.

I feel confident that Tesla will install a Supercharger halfway up to Truckee as more owners start towing. I look forward to trying it - there are RV camps along the way, so worst case I can stop for an hour and plug the car in, grab lunch, and then get back on my way. I could also just overnight in the beautiful Sierras, depending on my schedule.

Slowing down always helps as well.
ohmman is offline   Reply With Quote
Old 01-02-2017, 01:22 PM   #46
Vintage Kin
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 8,014
Images: 1
Towing with Electricity and a Model X

Quote:
Originally Posted by jcl View Post
I think understanding the "towing penalty" to range is critically important.



What I am not clear on is the comparison to an internal combustion engine (ICE).



Slowmover, you have previously referenced a 40% penalty as a rule of thumb. I have no info to dispute it. However, I saw you calculate it in a previous post as 21 mpg solo, 12.5 mpg towing, with a calculated 40% reduction. Importantly, that is a mpg difference, not a range difference. Using a standard liters/100km conversion, which puts consumption in the numerator, and thus creating figures that are logical to subtract one from another, the 21/12.5 shows a 68% increase in consumption. This would imply a 68% decrease in range. Using that yardstick, the EV figure of 74% higher consumption doesn't seem as far off. Add to that the energy recovery when descending, which an ICE can't do, and the unknown hill climbing penalty, and it gets even murkier.



Another metric would be cents per mile. Slow, you show an 80% penalty in CPM when towing, in your signature line, but I don't know what other factors are involved, and how many of them would carry over to an EV.



Interesting topic.



Jeff

Folks are going to compare operating cost of ICE to EV. Thanks for your points. We'll learn together.

At same travel speed over same level terrain in mild weather, solo is 25-MPG and towing is 15-MPG average at 58-mph.

At $2.25/gl diesel that 4.0-gls versus 6.66-gls. $9 versus $14.9

I've corrected the signature.

It's a forty percent difference (I was 3-cents high on towing and 1-cent low on solo).

Your point about 68 versus 74 helps.

The ICE 40% penalty was valid in 1967 and is valid in 2017. By being painstaking this can trend down towards 30%.

With a conventional trailer, towing can be a greater penalty. Up to 50%.

The range appears to be 35-45% for reasonable travel speed over non-mountainous terrain.

Our trailer design type is built to advantage in this regard.

While Airstream has become far too heavy the past thirty years, the shape is an excellent tradeoff between utility and aero qualities. "More" doesn't yield much aero wise. But it cuts capacities.

However, the weight could come down with no diminution in quality. But that only affects stop & go plus a few grade ascents. Longevity and reliability would be more affected.

As to regen, the test is the same. Departure and arrival back at the same point. An ICE is no less affected.
slowmover is offline   Reply With Quote
Old 01-02-2017, 01:54 PM   #47
jcl
Rivet Master
 
Currently Looking...
Vancouver , British Columbia
Join Date: Oct 2012
Posts: 1,928
Quote:
Originally Posted by slowmover View Post
Folks are going to compare operating cost of ICE to EV. Thanks for your points. We'll learn together.
Thanks for the detailed response.

Agree it is a 40% difference in MPG, but that is a problematic number to use. Canada went to l/100 km to avoid the issues in comparing mpg figures (ours were imperial gallons, not US gallons, but the same issue). People figured that a couple of mpg difference was the same benefit, whether they were going from 10 to 12, or 30 to 32. It wasn't.

Agree fully that people care about range, and cost (which are on the same scale). Instead of referring to a 40% reduction in mpg, the 67% increase in cost (and the same reduction in range), corresponding in your case to going from 9 cpm to 15 cpm, is what matters. Given that, it makes sense to me to not refer to a 40% mpg reduction, but rather a 67% increase in fuel consumption.

I don't think that the situation between the two propulsion types is comparable with respect to regen. An ICE going down a hill is making waste heat. An EV going down a hill is recovering useful energy that can be used on the next hill, or to extend range. This is the entire business case for hybrids, but in this case we are referring to hills more than stop/start, which is less a factor for towing.

Sometimes we want to calculate or measure range for other than a trip back to the starting point.

Cheers

Jeff
jcl is offline   Reply With Quote
Old 01-02-2017, 02:56 PM   #48
Rivet Master
 
2017 30' Classic
Anna Maria , Florida
Join Date: Jul 2013
Posts: 1,396
Quote:
Originally Posted by ohmman View Post
I've made a few posts discussing this, but today I took delivery of my 22 Sport. There were some issues during delivery with fit and finish. One of the windows has a gap between the front trim and the body. Insulation was coming through. Techs at my location (Bay Area Airstream Adventures) said that they were unable to close up the gap and that it's not uncommon. There are other window fitment issues that seem sloppy, but nothing that seems to be a major functional issue.

Some other careless details include window caulking issues, sink drain caulk, which is partially missing, stripped screw heads on the Fantastic Fan cover, some rusted screw heads on the outside of the vehicle, etc. Again, nothing terribly functional but also not terribly impressive for a leader in the RV world.

On to the good stuff - in general, it looks and tows well. The Tesla has absolutely no trouble pulling the Sport. I was able to accelerate rapidly when necessary, and I don't think I'll be hungry for more power. The issue with the electric drivetrain isn't power - it's range. On my way home, I drove an average of about 55 mph into gusty headwinds and crosswinds. I consumed about 580Wh/mi, which is about a 145 mile range on a full charge. To most of you with ICE tow vehicles, I'm sure that seems meager, but for me, 2.5 hours of towing is fine time for a break. We'll see how that works out in real life.

I got the Sport home and, being that this is my first trailering experience, spent a little time backing it into the perfect spot. I took a few passes, trying to get the hang of it. Overall, I felt I did well. Best to practice at home when nobody's there to laugh at me, right? Well, my wife was grinning.. but hopefully she was just glad I was home.

I'll update more as to the ups and downs of towing with my X. For now, I'm excited for our first jaunt to the beach.
Towing with a Tesla is a joke.
franklyfrank is offline   Reply With Quote
Old 01-02-2017, 03:18 PM   #49
Rivet Master
 
SteveSueMac's Avatar

 
2012 27' Flying Cloud
W , New England
Join Date: Oct 2012
Posts: 7,171
Quote:
Originally Posted by franklyfrank View Post
Towing with a Tesla is a joke.

Thanks - with all the frivolous data and experience provided so far, finally a cogent argument to settle the issue once and for all. I can rest easier now in my decision to forgo the Tesla purchase.

😳

(In case it's not obvious, that was intentionally sarcastic)
SteveSueMac is offline   Reply With Quote
Old 01-02-2017, 03:26 PM   #50
3 Rivet Member
 
2017 22' Sport
North Bay , California
Join Date: Nov 2016
Posts: 224
Images: 11
Quote:
Originally Posted by jcl View Post
I don't think that the situation between the two propulsion types is comparable with respect to regen. An ICE going down a hill is making waste heat. An EV going down a hill is recovering useful energy that can be used on the next hill, or to extend range. This is the entire business case for hybrids, but in this case we are referring to hills more than stop/start, which is less a factor for towing.

Sometimes we want to calculate or measure range for other than a trip back to the starting point.
Thanks for this - exactly the case. You can also compare return to starting point and see the difference between ICE and EV. What if I departed, drove up a 9% grade for 50 miles, and turned back around to return to my starting point? The EV would be able to recapture a lot of the excess energy expended (it's around 80%) on the return trip. An ICE wouldn't. On the other hand, imagine that my hypothetical includes a 200 mile climb at 9% grade. The EV would never make it while towing (without a charge), but the ICE would make it and be able to coast back downhill.

The problem with comparing EV with ICE is that the end goals are different. They both revolve around efficiency, but for an ICE, that efficiency is tied almost exclusively to the cost of travel. With an EV, the efficiency is important because of range and a fledgling charging infrastructure. My goal is currently efficiency for the purpose of range. Once the Supercharger v3 stations come out and battery capacities increase, range will be less of a concern.
ohmman is offline   Reply With Quote
Old 01-02-2017, 03:57 PM   #51
Rivet Master
 
2012 19' International
Southeastern MI , Michigan
Join Date: Aug 2016
Posts: 2,057
Quote:
Originally Posted by SteveSueMac View Post
Thanks - with all the frivolous data and experience provided so far, finally a cogent argument to settle the issue once and for all. I can rest easier now in my decision to forgo the Tesla purchase.

😳

(In case it's not obvious, that was intentionally sarcastic)
People who poke fun at electric vehicles will stop laughing when gas goes back to $6 like the rest of the world is paying.

I think towing with a Tesla is the ultimate adventure.
__________________
2018 International Serenity 27' FB
Michelin 16” tires
Hensley Arrow hitch

Tow Vehicle: Ram Laramie 2500 crew cab, Cummins 6.7 Turbodiesel
Countryboy59 is offline   Reply With Quote
Old 01-02-2017, 04:05 PM   #52
Rivet Master
 
SteveSueMac's Avatar

 
2012 27' Flying Cloud
W , New England
Join Date: Oct 2012
Posts: 7,171
Quote:
Originally Posted by Countryboy59 View Post
People who poke fun at electric vehicles will stop laughing when gas goes back to $6 like the rest of the world is paying.



I think towing with a Tesla is the ultimate adventure.

I'd be all over this:

http://www.teslarati.com/tesla-picku...-duty-segment/
SteveSueMac is offline   Reply With Quote
Old 01-02-2017, 04:22 PM   #53
Rivet Master
 
Piggy Bank's Avatar
 
2019 27' Flying Cloud
Kansas City , Missouri
Join Date: Apr 2014
Posts: 1,485
Not to dissuade emerging technology, but even at $6 a gallon that's about the same price as Coca Cola. And I think we would all agree that on the whole Gas or Diesel is harder to bring to market and more valuable than a soft drink.

In the vast midwest, it will take a sea change in range for anything to displace the ICE.

Doesn't mean that early adapters should not proceed. But we are a long way away from mass applicability.
__________________

Piggy Bank
Piggy Bank is offline   Reply With Quote
Old 01-02-2017, 04:54 PM   #54
3 Rivet Member
 
2017 22' Sport
North Bay , California
Join Date: Nov 2016
Posts: 224
Images: 11
Quote:
Originally Posted by Piggy Bank View Post
In the vast midwest, it will take a sea change in range for anything to displace the ICE.

Doesn't mean that early adapters should not proceed. But we are a long way away from mass applicability.
For towing, I agree. For general driving, I disagree. There are many happy Tesla owners throughout the US. Lots of owners drive cross-country semi-regularly. I nearly drove cross-country over Thanksgiving when, two days before a scheduled flight to the East Coast, my young daughter came down with a severe ear infection and was told by her pediatrician that she couldn't fly. I about packed her in the Tesla and drove out. My wife talked sense into me, as putting a sick kid in the back of a car for 3 days isn't exactly thoughtful either, but the broader point is that it's not hard.

Based on the evidence to date, I don't think it's unreasonable to assume that within 2 years we'll have 350-400 mile range EVs that have the ability to charge at 350-500kW. Refueling will be very nearly as convenient as gas. Assuming that vehicle costs are comparable, I do think it'll be a tipping point for mass adoption outside of the coasts.

But that's all a bit off topic. We have a short (non-camping) trip planned very soon, but when we get back, I'm doing a little work to the Airstream and we'll be off on our first camping trip. First one - a short overnight to the beach. No vehicle charging. I want to start simply and learn what I don't know first.
ohmman is offline   Reply With Quote
Old 01-02-2017, 05:49 PM   #55
Vintage Kin
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 8,014
Images: 1
For those with an interest in range, I'd suggest, "What's my ideal minimum?"

Without respect to TV type.

One, I long ago settled on 500-miles of usable diesel (80% of maximum = 30/gls at present; I need another 5) at my present average of 15-MPG under normal circumstances. As a "normal" day of towing is less than this, it affords flexibility in trip planning.

Two, under abnormal circumstances (until last year, hurricane evacuation for me) one needs to be at least 150-miles out of the zone before fuel supplies normalize. This is figured at 3-5/MPG for idling in bumper to bumper traffic.

No vehicle, tiny Honda or my 8000-lb pickup does any better in MPG. Biggest fuel tank for the win.

So, fifty gallons of diesel for this combined rig. Aftermarket has 60-gallon replacement tanks. 80% is 48-glad which is close enough. A pair of 5/gl fuel jugs is enough as backup. On my list.

(14-16/MPG is usual range for a truck like mine; and typical for owners with an early HPCR Cummins pulling a 27-35' aero all aluminum trailer of our type weighing from 7-11,000-lbs in the South Central US at about 55-63/mph; I found just over one dozen comps ten years ago. The latest DEF tuned ones should be similar The combined rig weights would be about 15-20k).

Convenience is nice. But the hard numbers to make these trailers effective tools -- the family Conestoga -- may also be valued.
slowmover is offline   Reply With Quote
Old 01-02-2017, 05:52 PM   #56
Vintage Kin
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 8,014
Images: 1
Quote:
Originally Posted by Piggy Bank View Post
Not to dissuade emerging technology, but even at $6 a gallon that's about the same price as Coca Cola. And I think we would all agree that on the whole Gas or Diesel is harder to bring to market and more valuable than a soft drink.

In the vast midwest, it will take a sea change in range for anything to displace the ICE.

Doesn't mean that early adapters should not proceed. But we are a long way away from mass applicability.

For a tow vehicle a hybrid drivetrain makes the most sense. See the Nikola commercial truck (semi tractor). See also the Westlake [?] LNG trucks.
slowmover is offline   Reply With Quote
Old 01-02-2017, 05:56 PM   #57
3 Rivet Member
 
2017 22' Sport
North Bay , California
Join Date: Nov 2016
Posts: 224
Images: 11
Quote:
Originally Posted by slowmover View Post
For those with an interest in range, I'd suggest, "What's my ideal minimum?"

Without respect to TV type.
I recognize you don't see the value in EVs, but this thread is truly about the opposing view that you lay out. That is, I'm constrained by the TV. The TT is secondary. Therefore, I find the TT that works for me and figure out how to make it work, convenient or not. And that's what I plan to report in this thread.
ohmman is offline   Reply With Quote
Old 01-02-2017, 06:13 PM   #58
Vintage Kin
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 8,014
Images: 1
Quote:
Originally Posted by ohmman View Post
I recognize you don't see the value in EVs, but this thread is truly about the opposing view that you lay out. That is, I'm constrained by the TV. The TT is secondary. Therefore, I find the TT that works for me and figure out how to make it work, convenient or not. And that's what I plan to report in this thread.

You've entirely misread everything I've posted in this thread.

Questions about range are always germane.

The TT design is fundamental to that question. Aero is huge. Weight is only relative.

TV type is interchangeable for many if not most AS trailers. EV is simply new. And currently limited.

But what are the limits? It isn't AS TT weight, per se.

Mines simply another drivetrain with an almost different class of rig (size and weight) despite similarity.

All of us are bound by what we have. I've explored some limits on mine and reported them. It's pretty well a hard limit.

What range is "acceptable" is personal.

But even the latest diesel vehicles aren't any better today than they were a dozen years ago.

EV is a whole other thing.

The tech aspect is interesting to some.

Maybe not to you.
slowmover is offline   Reply With Quote
Old 01-02-2017, 06:22 PM   #59
jcl
Rivet Master
 
Currently Looking...
Vancouver , British Columbia
Join Date: Oct 2012
Posts: 1,928
Quote:
Originally Posted by slowmover View Post
For a tow vehicle a hybrid drivetrain makes the most sense. See the Nikola commercial truck (semi tractor). See also the Westlake [?] LNG trucks.
That would be Westport Innovations. Know it well. I worked on product development of cryogenic fuel storage for on and off road trucks, rail, and marine. Other teams did CNG instead of LNG, for lighter duty applications (eg Ford WiNG), and transit.

Back to EVs. ;-)
jcl is offline   Reply With Quote
Old 01-02-2017, 06:28 PM   #60
jcl
Rivet Master
 
Currently Looking...
Vancouver , British Columbia
Join Date: Oct 2012
Posts: 1,928
Quote:
Originally Posted by Countryboy59 View Post
People who poke fun at electric vehicles will stop laughing when gas goes back to $6 like the rest of the world is paying.

I think towing with a Tesla is the ultimate adventure.
We went to $1.52 per litre for premium yesterday at the station down the road from me. That is $6.90 per Imperial gallon, which is getting close to $6 CDN per US gallon.

Agree totally that towing with a Tesla is a fantastic adventure.
__________________

jcl is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
electricity and blinds finn2020 Upholstery, Blinds, Walls & Interior Finishes 1 08-08-2007 10:27 AM
I always camp where I have electricity happier General Appliance Topics 13 07-27-2007 03:09 PM
Electricity in 1959 Traveler? and awnings? r&kweber 1959 Traveler 8 08-03-2006 11:08 PM
The mysterious world of electricity, or...... krowsea Electrical - Systems, Generators, Batteries & Solar 25 09-03-2004 04:23 PM
Connecting to Electricity ssolid Electrical - Systems, Generators, Batteries & Solar 22 02-12-2004 09:09 AM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:24 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.