Go Back   Thor Forums > Thor Tech Forums > Motorhome Tech Topics
Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 06-22-2015, 07:20 PM   #21
Senior Member
 
dstankov's Avatar
 
Brand: Thor Motor Coach
Model: 2015 Challenger 37ND
State: Virginia
Posts: 3,100
Quote:
Originally Posted by Chance View Post
The engine would most likely run at same speed but slightly higher torque to produce the extra power. Large motorhomes like yours cruise at roughly 100 HP on level roads, so an additional 1 to 5 HP would not necessarily require different gearing or downshifts just because of relatively-minor extra alternator load.

...
Interesting concept, however, how many people limit driving their coaches to "level roads" 85 - 90 percent of my annual camping is in the mountains so any drain to Horse Power is significant.

Even when travelling to Florida I am travelling along rolling terrain.

Sorry, until the option is available for between 2,000 - 3,000-dollars, to include solar array, I can not see any type of economic benefit to it's implementation.

Has any one seen any type of reliability or "Total Cost of Ownership" to support that type of option? I do know a lot of folks that have the all electric coaches have all kinds of problem with the electronic control systems and components.
__________________

__________________
Dave
US Army (Ret)
Chester, VA
2015 Thor Challenger 37ND
FMCA - F432054
dstankov is offline   Reply With Quote
Old 06-22-2015, 07:35 PM   #22
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by dstankov View Post
....cut....

The point I was making is there are tradeoffs. If adding the additional alternator increase fuel consumption from 8 to 6 MPG how many people are going to back away from the market.

Also, a 13,000 dollar option package at 2.50 per gallon will buy over 5,000 gallons of fuel, which at .9 gph of gen run time equates to 5777 hours. The break even point for me would be somewhere in 8 to never range. My prior coach had less than 300 hours on the generator and my current coach has less than 50.

For me to shell out that kind of money for a coach where I have to kneel in the aisle to load the refrigerator and never see a return on investment just doesn't make any sense outside the "cool factor". I buy practical and useful, I don't by cool especially since cool is usually short lived or constantly changing.
Dave, a large motorhome uses roughly 10 gallons per hour during cruise, right? That's 70 MPH while getting 7 MPG. Running an alternator would no doubt have to reduce vehicle MPGs somewhat, but I don't see how total fuel consumption would be any more than if running a separate Onan generator engine that burns close to 1 GPH. Incremental load on a Ford V10 is much more efficient than a small Onan engine running lightly loaded.

And you are correct that the E-Trek is expensive, but it is not $13,000 additional over a traditional generator. Not even close. Minus solar charging it runs the same price as an installed diesel generator. And I'm asking about this system in place of and not in addition to a generator.

Granted a gasoline generator is less expensive, but I've checked the cost of components and if mass-produced in larger volumes a system like E-Trek would be far less expensive. They are basically adding a 150 Amp X 24-Volt engine-driven alternator, a few extra 200 Amp-hour 6-Volt AGM batteries, and upgrading the size of the inverter (a smaller is standard). This should all cost less than $3,000 which is comparable to a Onan generator.

The Roadtrek is no bargain, but that it cost way too much has nothing to do with the E-Trek option. If I recall correctly, Roadtrek offers this system on cheaper Class B motorhomes too. To be honest, I don't care about the merits of the coach itself because I would never buy one like it. The electrical power generation is a different matter -- I can see it working better for me than a traditional generator 95% of the time.
__________________

Chance is offline   Reply With Quote
Old 06-22-2015, 08:06 PM   #23
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by dstankov View Post
Interesting concept, however, how many people limit driving their coaches to "level roads" 85 - 90 percent of my annual camping is in the mountains so any drain to Horse Power is significant.

Even when travelling to Florida I am travelling along rolling terrain.

Sorry, until the option is available for between 2,000 - 3,000-dollars, to include solar array, I can not see any type of economic benefit to it's implementation.

Has any one seen any type of reliability or "Total Cost of Ownership" to support that type of option? I do know a lot of folks that have the all electric coaches have all kinds of problem with the electronic control systems and components.
I used 100 HP on level road as an example to put your estimate into proper context. Yeah, in hills and mountains that big V10 can also make 300 HP, right? So what, it doesn't change the fact that as a percent of engine power an alternator is a very small load. And beyond that it can be cut off when engine is nearing it's capacity so it would have no effect at all on hill climbing. That technology is already in use and becoming common.

If value is based strictly on cost, then an Onan is probably the only right solution. For me cost is not the only factor. At the North Rim recently I wanted to make coffee and use the microwave during periods the generator wasn't allowed. I would have happily paid a premium for a system with capabilities like the E-Trek's.

Based on opinions expressed above on how generators end up getting used, plus my own too, I think a similar system to the E-Trek in lieu of a traditional generator would be something I would buy in a new RV if offered as a reasonably-priced option.
Chance is offline   Reply With Quote
Old 06-22-2015, 09:07 PM   #24
Senior Member
 
dstankov's Avatar
 
Brand: Thor Motor Coach
Model: 2015 Challenger 37ND
State: Virginia
Posts: 3,100
Quote:
Originally Posted by Chance View Post
...
Based on opinions expressed above on how generators end up getting used, plus my own too, I think a similar system to the E-Trek in lieu of a traditional generator would be something I would buy in a new RV if offered as a reasonably-priced option.
I do not disagree with this point in any way shape or form. Each individual must make their own decision based on what is important to them.

I started working on vehicles using 24 volt primary and auxiliary charging systems, as well as some having an on board 12 volt chassis system for in the 1960s. Our vehicles used battery banks ranging from 2 to 8 deep cycle 12 volt batteries (wired in series - parallel) which in the 1970s were costing over 600.00 each (and the price has not reduced much since due to low demand) . Although I will not discuss specifics if you can locate it, and it is doubtful you will, try to find info on the heat related failure rates of auxiliary high output alternators in automotive charging applications. You may find that due to the high levels of heat generated by the alternator the estimated life expectancy is somewhere around 6 months at light to mid level usage (2 - 3K miles per year). You may also find that in cold climates the cost heating and cool down cycles of electrical components and wiring is relatively high since these conditions tend to make wiring brittle. You may also find that batteries charged at these levels last about 18 months and have a tendency to boil over when charged at high levels of power. The batteries also have an associated weight factor and here again there is a trade off. The extra battery weight means something stays behind so will that be water, food or something else.

The technology has been around for over 50 years so ask yourself why hasn't it made its way into a wider spread of applications such as the RV industry.

Until someone would have to come up with some strong supporting evidence that the reliability has significantly improved I will shy away from the systems.

Again, each individual must make their own decision based on what is important to them.
__________________
Dave
US Army (Ret)
Chester, VA
2015 Thor Challenger 37ND
FMCA - F432054
dstankov is offline   Reply With Quote
Old 06-23-2015, 04:17 AM   #25
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by dstankov View Post

.....cut.....

The technology has been around for over 50 years so ask yourself why hasn't it made its way into a wider spread of applications such as the RV industry.

Until someone would have to come up with some strong supporting evidence that the reliability has significantly improved I will shy away from the systems.

....cut.....
Costs. Until recently costs were too high to make it practical and a viable option.

I've used related technology (slightly more complex) in industry for decades and the cost was initially extremely high even for large corporations to justify.

Regarding heat issues with high-capacity alternators, I think the devil is in the details. No doubt that when some aftermarket small company tries to fit a +300-Amp alternator in the same space that the factory had a 130 Amp unit, that reliability can suffer. That's just common sense.

On the other hand, if designed properly for the expected load, capacity shouldn't be an issue. In industry you can buy a 100 HP motor that runs just as cool and lasts just as long as a 10 HP motor. Obviously it's a lot bigger. My point is that capacity in itself doesn't have to be an issue.

Besides, there are easy ways to get around what you are concerned about regarding heat. For instance, if we do a little reverse engineering, we can estimate that the 3500 watt alternator used by Roadtrek is probably rated at 250 Amps at 14 Volts (that's standard for 12-Volt systems). While higher capacity than alternators of the past, that level of current is now common on Mercedes Sprinters and Ford Transits. OEM alternators with capacity over 200 Amps are fairly common.

To make things more reliable all we need is to increase voltage in order to reduce current, which is the primary reason for heat. The E-Trek system is rated at 3500 watts, but at 24 Volts nominal. That means the alternator they use is likely rated at 125 Amps at 28 Volts. And personally, I'd feel very comfortable with 125 Amps or less.

Other than driving costs lower still, I don't see any technical limitations that can't be worked out with a little effort. Whether the system can meet my needs better than a generator is of greater concern.
Chance is offline   Reply With Quote
Old 06-24-2015, 03:22 PM   #26
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
I was curious about the extent of added weight so I did some checking.

Added weight with 8 AGM batteries like the E-Trek uses can indeed affect the coach's cargo carrying capacity. With more expensive lithium batteries the difference seems insignificant for the most part.

The 6-Volt 200AH AGM batteries weigh between 60 and 65 pounds each, for a total weight of around 500 pounds. This adds about 350 pounds to coach compared to a 4,000 watt gasoline Onan.

These would have a total capacity of 9,600 watt-hours, of which roughly half is useable to keep from damaging the batteries. Hence about 4,800 watt-hours are available.

Since lithium batteries can be discharged down to 20%, in order to have the same 4,800 watt-hours of available energy, installed capacity would need to be 6,000 watt-hours.

Using specs and prices for RV deep-cycle lithium batteries I can find, 6,000 watt-hours would weigh about 140 pounds and cost just under $5,000. Cost is roughly twice that of using AGM batteries if of well-known brand.

So it seems that to replicate the E-Trek system it either adds weight or cost. That's not to say that the same amount of battery capacity is needed depending on individual usage.

If/when lithium batteries come down in price as Tesla has predicted, then both weight and costs will be comparable to a conventional generator. Then it would come down mostly to which works best for our individual needs.
Chance is offline   Reply With Quote
Old 06-24-2015, 04:14 PM   #27
Senior Member
 
JamieGeek's Avatar
 
Brand: Thor Motor Coach
Model: Axis 24.1
State: Michigan
Posts: 6,272
Quote:
Originally Posted by Chance
If/when lithium batteries come down in price as Tesla has predicted, then both weight and costs will be comparable to a conventional generator.
Battery costs are dropping, and fast: The Price of Electric Car Batteries is Dropping Fast

My EV's Li-Ion batteries weigh in around 600lbs for 23kWh of capacity (about 19kWh of which is usable to ensure the battery lasts longer) for point of reference (Ford had initially said the battery costs $12,000 but that was four years ago--I'm sure its price has fallen now).
__________________
2014 Thor Axis 24.1
2016 C-Max Energi
2018 Chevy Bolt
blog - https://spareelectrons.wordpress.com/
JamieGeek is online now   Reply With Quote
Old 06-24-2015, 04:17 PM   #28
Senior Member
 
DocMike's Avatar
 
Brand: Thor Motor Coach
Model: Vegas 24.1
State: North Carolina
Posts: 1,491
Lowes RAVEN

Quote:
Originally Posted by dstankov View Post
I was looking at a riding mower a week ago that has the ability to flip a switch and it converts from mower to generator to power electric tools such as trimmers or pole saws. At $5,000 I thought it was a little pricey and want to see which direction the price heads and what type of demand they have for the units.
Lowes has the Raven Hybrid Riding Lawn Mower/Generator with a Quick Transport mode (up to 17 MPH)...at $3999. My local Lowes had a used/refurbished one for $3250.00, it was gone before I could go home and get back with the Truck.
__________________
Sheree & Michael NCNG LTC(ret) with Satin Doll & Munpi.
2016 Vegas 24.1 E350 5 speed "Ms. Enterprise", Bug-Guard Screen, Recliners, Infotainment Center, HUD, ARC Shower Rod, Safe-T-Plus, Curt SpareTire Mount,Tornado Black Tank Rinser, ext. WiFi Antenna, Roadmaster Tow Sys& Invisibrake.

DocMike is offline   Reply With Quote
Old 06-24-2015, 04:59 PM   #29
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by JamieGeek View Post
Battery costs are dropping, and fast: The Price of Electric Car Batteries is Dropping Fast

My EV's Li-Ion batteries weigh in around 600lbs for 23kWh of capacity (about 19kWh of which is usable to ensure the battery lasts longer) for point of reference (Ford had initially said the battery costs $12,000 but that was four years ago--I'm sure its price has fallen now).

Jamie, from article:

"Progress in battery costs
The researchers delved into battery costs for vehicle manufacturers between 2007 and 2014, charting the decline from $1,000 per kWh to around $300 per kWh in recent figures for the top companies — a number that was expected to be years away for automakers and battery producers. A benchmark of $230 per kWh was even considered feasible by as early as 2017."

The $300 per kilowatt-hour cost target is what I've read or heard often in last year or so. If we could buy RV batteries at that price today it would be a game changer.

The best I could find doing a quick Google search was around $1,000 for 1200 watt-hours, which works out to well over $800 per kWh.

If I could buy 6 kWh of lithium batteries for under $2,000 I wouldn't consider a traditional generator like the one I had at all. I didn't use it enough. I "may" carry a Honda as a backup but even that is doubtful.
Chance is offline   Reply With Quote
Old 12-02-2015, 06:49 PM   #30
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Apparently we are getting much closer to the day when conventional generators won't be needed on most motorhomes. Displayed at Louisville industry show this week, it has high capacity lithium battery pack, 10,000 watt 48 Volt alternator, large capacity inverter and converter.

Cost is probably still too high except for luxury motorhomes -- just a guess on my part. Hope the trend continues in this direction.


Volta Power Systems | ADVANCED INTEGRATED ENERGY STORAGE SOLUTION FOR YOUR POWER NEEDS
Chance is offline   Reply With Quote
Old 12-02-2015, 07:24 PM   #31
Senior Member
 
RustyJC's Avatar
 
Brand: DRV
Model: Mobile Suites 38RSSA
State: Texas
Posts: 206
Quote:
Originally Posted by blw2 View Post
an onboard generator was on my high list....a primary reason for getting a motorhome over a TT.
I'm not boondocking for days running it 24/7, but I love the ability to run the AC off grid.
We use it on super hot days on the highway for the house AC, and have used it a few times stopping for a few hours in the evening before bed or for a lunch break or such.... and for my morning coffee
Actually, our 5th wheel (see signature) has a "semi" generator prep with a 50 amp Marinco twist-lock receptacle on the front of the 5th wheel. We use 2 each Yamaha EF2000iS generators running in parallel in the bed of the truck to provide almost 30 amp service to the 5th wheel via a 30-to-50 adapter and 30 amp cord when we're on the road and want to run one A/C to precool the RV. A similar setup could be used in the rig you're discussing for boondocking if you didn't want to run the Mercedes coach engine to power the generator.

Rusty
__________________
Rusty, Sandy, 2 Shelties (Coby & Callie) & Conner the Campground Cat
2016 Ram 3500 Longhorn Crew Cab 4x4 Dually, 385/900 Cummins, Aisin AS69RC, 4.10 axle, 39,100 GCWR, 30,050 trailer tow, B&W RVK3600
Current: 2014.5 DRV Mobile Suites 38RSSA #6972 - Previous: 2004 MS 36RE3 #1291
RustyJC is offline   Reply With Quote
Old 12-02-2015, 09:32 PM   #32
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
The Volta system (or one like it) should easily allow running a motorhome's house AC while driving off engine power. It should also run one AC most of a night from the 13.5 kW-hour battery bank. Running a microwave, coffee maker, or TVs off such a system should also be easy.


Volta Touts ‘Lithium Ion Energy’ for RVs at RVIA | RV Business

“Our half pack contains 13.5Kwh of energy. That’s equivalent to 19 group 31 batteries or 1995Ah,” Johnson noted. “That’s more than a thousand pounds of weight savings and more energy to power comfort and convenience.”
Chance is offline   Reply With Quote
Old 12-02-2015, 10:08 PM   #33
Senior Member
 
dstankov's Avatar
 
Brand: Thor Motor Coach
Model: 2015 Challenger 37ND
State: Virginia
Posts: 3,100
The thing I find interesting is although they claim the system is good for RV applications they do not mention a single manufacturer that has placed the system in use; not even a high end multi million dollar coach.

Also when you try to use the locate a dealer feature there are none listed rather they say to contact the company themselves.

Since they configured a bus to run this system for demonstrations in July 2014 one must ask the question, What have they done since then?

To me, and this is only my opinion, the system is still 5 to 10 years from being readily available for application on an RV the average schmuck like me is willing to purchase.

I did notice, however, that their latest news release was they were going to be at the FMCA Family Reunion in Madison Wisconsin. That reunion ended August 1st and there is no mention or product review anywhere on FMCA's site, at least non that I can find.

It has merit and sounds good, now what's the real deal?
__________________
Dave
US Army (Ret)
Chester, VA
2015 Thor Challenger 37ND
FMCA - F432054
dstankov is offline   Reply With Quote
Old 12-02-2015, 11:09 PM   #34
Senior Member
 
JamieGeek's Avatar
 
Brand: Thor Motor Coach
Model: Axis 24.1
State: Michigan
Posts: 6,272
Quote:
Originally Posted by dstankov
It has merit and sounds good, now what's the real deal?
I'm guessing none of the manufacturers bit--its probably too different for them, or too costly compared to the typical genny setup.

Quote:
Originally Posted by Chance
The Volta system (or one like it) should easily allow running a motorhome's house AC while driving off engine power. It should also run one AC most of a night from the 13.5 kW-hour battery bank. Running a microwave, coffee maker, or TVs off such a system should also be easy.
Their website specifies a 3.6kW inverter..seems a little light for running the A/C.
Quote:
Our industrial grade 3600W of 120VAC output inverters have been specially developed to work with lithium ion in order to maximize performance and safety.
__________________
2014 Thor Axis 24.1
2016 C-Max Energi
2018 Chevy Bolt
blog - https://spareelectrons.wordpress.com/
JamieGeek is online now   Reply With Quote
Old 12-03-2015, 01:10 AM   #35
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by JamieGeek View Post
....cut...

Their website specifies a 3.6kW inverter..seems a little light for running the A/C.
Jamie, I think that's plenty as long as it can handle the start-up lock-rotor current. Many of the RV roof-mounted ACs only pull between 1000 and 1500 watts, depending on size and whether they are high efficiency models.

There are guys running smaller AC models in vans with a 2000 watt inverters. A 3600 watt industrial unit should be able to run an AC and microwave simultaneously.
Chance is offline   Reply With Quote
Old 12-03-2015, 01:40 AM   #36
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Quote:
Originally Posted by dstankov View Post

....cut....

To me, and this is only my opinion, the system is still 5 to 10 years from being readily available for application on an RV the average schmuck like me is willing to purchase.

....cut...
I think timing mostly depends on battery costs. If lithium batteries continue to drop at present rate, the systems will be available in a few years.

I also think that we will adopt the system's concept gradually. In reality it's already being done in smaller scale.

Some Class Bs already have a second engine-driven high-capacity alternator, large inverter/charger, and large battery bank. And no generator.

These innovative systems have been around at least a couple of years now, and are only limited by battery bank capacity, weight, and cost.

Since most high-end motorhomes will have inverters anyway, and a second alternator doesn't add that much cost (about $400), it comes down mostly to lithium battery bank cost. And at projected costs, 13.5 kW-hours of batteries should be around $4,000, the cost of a typical generator.

Buyers first have to perceive these kinds of systems as superior to generators before they give them a try, but in my opinion that depends greatly on battery bank capacity. That's why lower-cost batteries are so important.
Chance is offline   Reply With Quote
Old 06-17-2016, 07:48 PM   #37
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
an update affecting this topic....

Finally an interesting automotive development that represents another step in this direction.

For about 20 years the auto industry kicked around the idea of upgrading to a 36-Volt electrical system to replace the existing 12-Volt system, but nothing much came of it. Agreement on the upgrade was more complicated than the previous switch from 6- to 12-Volts. Higher-voltage hybrid and electric cars also made many question whether a new electrical standard was even needed at all.

Now it appears the auto industry is converging on a 48-Volt system which should be even better for the future of motorhomes. Auto manufacturers and their suppliers are acting to improve fuel economy (a lofty goal in itself), but to me the potential for improvement that an inexpensive high-capacity 48-Volt electrical system should offer motorhomes is much more interesting.

Best of all, they are talking about a cost premium in order of $1,000, leaving plenty on the table for added battery capacity compared to conventional generators. Please note I'm not suggesting these components are large enough to serve as part of a hybrid system for motorhomes, but rather will lead to affordable upgraded electrical systems that may not require the typical Onan for many RVers.

These give a little background:

Mercedes announces inline-6 with 48-volt mild hybrid system

48-volt mild hybrid systems: what they do, how they change the car

Why You Should Pay Attention To 48-Volt 'Hybrids'
Chance is offline   Reply With Quote
Old 06-17-2016, 08:32 PM   #38
Senior Member
 
JamieGeek's Avatar
 
Brand: Thor Motor Coach
Model: Axis 24.1
State: Michigan
Posts: 6,272
As I understand it: Delphi came up with the system and was shopping it around to OEM's as a less expensive system to the high-voltage hybrids:
Delphi Touts 48v Charging system
__________________
2014 Thor Axis 24.1
2016 C-Max Energi
2018 Chevy Bolt
blog - https://spareelectrons.wordpress.com/
JamieGeek is online now   Reply With Quote
Old 03-13-2018, 08:02 PM   #39
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 3,094
Winnebago Travato offers Volta 48-Volt electrical

Quote:
Originally Posted by dstankov View Post
The thing I find interesting is although they claim the system is good for RV applications they do not mention a single manufacturer that has placed the system in use; not even a high end multi million dollar coach.

.....cut.....

To me, and this is only my opinion, the system is still 5 to 10 years from being readily available for application on an RV the average schmuck like me is willing to purchase.

.....cut.....
Technology moving faster than expected?

Not to pick on Dave's estimate (just using as example), but it took less than 2 years for Advance RV to start using the Volta 48-Volt system on their Class Bs, and now Winnebago just announced the Volta system will be available in the Travato Class B line, making it the first high-volume manufacturer to offer the Volta system as far as I know. Hymer and Coachmen (using Xantrex) have also replaced the conventional generator, but stayed with 12-Volts which I think is a mistake.

The Travato system has 3,600 Watt (30-Amp) inverter, 8,700 watt-hour of lithium battery pack, and an engine-driven 58-Volt alternator that is reportedly twice as powerful as the competition's. I presume they are comparing to 280 Amps X 14 Volts, so alternator is probably in the range of +/- 8,000 watts (wild educated guess). With proper duty cycle the battery bank should be recharged in approximately +/- 1 hour.

We're getting very close -- price is still a little high but should come down with volume.
Chance is offline   Reply With Quote
Old 03-13-2018, 08:16 PM   #40
Senior Member
 
saddlesore's Avatar
 
Brand: Thor Motor Coach
Model: SOB
State: Oregon
Posts: 406
Nope...read the article.... still nope
__________________

__________________
current coach
SOB (some other brand)
former coach
Thor Infinity
saddlesore is offline   Reply With Quote
Reply

Thread Tools
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


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Thor Industries or any of its affiliates. This is an independent, unofficial site.




All times are GMT. The time now is 08:25 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0 PL2