Electrical, Solar, Lithium Batteries on 28' International

[wbrown]

Introduction

My wife and I just purchased a 2014 28' International Serenity, and we pick it up next week. We're excited! However, the electrical system as is doesn't fit our needs -- especially my needs as a paid technonerd and engineer.

Our new International has the factory installed 1000W inverter, and two stock lead acid batteries, as well as 50a service. The inverter is probably going to be the first thing to go -- I was primarily interested in it as a way to get two separate circuits or more plugs; the amount of plugs available just about doubles.

I've been doing a lot of research and thinking about the electrical and power system, with an eye towards boondocking quite a bit. If any forum members are somewhere in the Georgia or Florida area and are electrically inclined, or have a recommendation of who to work with, I'd be happy to have the system professionally done. I've sketched out the following major systems, and would appreciate feedback.

• Solar
• Battery Bank
• Inverter
• Generator

So, addressing them in order ...

Solar

Obviously, solar would make boon docking a whole lot easier; it would be a huge plus if I can go without running a generator.

After reading much of this sub forum, the two major contenders in my mind are:

• * Solar Kit from AM Solar -- Solar Panel Kits with Mounts, Roof Wire Harness, and Accessories
  * Go Power Flexible Solar -- Solar Flex Kits and Modules (Flat, bendable) | GPElectric

I am having a hard time finding any information on the roof layout of the 28' International Serenity. I did take a few pictures by standing on the bumper, with my iPhone held up. One complicating factor as far as the roof line and placement is that we have a second AC unit.

Left side of the airstream, right side is pretty similar.

https://www.icloud.com/photostream/#...A-BC0C6CFB10DD

Layout wise, there appears to be room to the left and right of the bedroom AC unit, and perhaps room forward of the vents, next to the front bedroom AC. Does anyone have any experience with the 2014 28' Internationals, and the roof layout?

As Twinkie is not a vintage Airstream, I think I could put panels that are a bit more than two feet wide on each side, such as the GO160 -- which is 26" wide, and 58" long. Failing that, I could use GS100's -- which are 20.75" wide, and 40" long.

I am quite tempted by the Go Power flexible panels -- due to the aerodynamic profile, and the lack of visibility on the roofline -- I am aware of the potential for heat issues with the lack of circulation so that makes me hesitate. With that being said, I could put GP-FLEX-100's on -- which are 21.3" wide and 41.7" long -- very close to GS100's. The huge advantage for me is that they are much much lighter than the traditional panels -- an important consideration as I have a half ton truck and a relatively high tongue weight.

I am interested in squeezing as many watts out of a solar system as feasible given the roofline -- how many panels do you all think I can put up there sensibly?

It appears that either way, I'd use a SunRunner MPPT core or the 30A PWM core that comes with the Go Power kits. I think that also depends on what I end up with for the rest of the system.

Battery Bank

The Twinkie comes with two lead acid cells, apparently in the 75 ah range. Completely insufficient, and they will have to be replaced with AGMs at the very least to best leverage a solar system.

The current best practice is to use AGM batteries. As Twinkie is a rear bedroom model, putting a large GPL-8DL under the bed is impractical -- I'd have to run a lot of wiring up from the back towards the front where the electrical system is.

It appears that I can use the under the couch storage -- there is an easily accessible part. There is also an under-couch compartment to the left that contains the 1000W inverter. I can also use the battery compartment that contains the lead acid batteries.

Dimensions are:

• Under Lounge Front (54"w, 12"h, 12"d)
• Lounge Inverter Compartment (offset from inverter, 16"w, 12"h, 14"d, opening is 16"x8")
• Battery Box (15"w, 12"d, 10" high)

If I use LifeLine AGM batteries, it appears that I could replace the battery box lead acids with GPL-24T's which have the following dimensions:

• GPL-24T (7", 6.6", 9.2")

It may be a tight squeeze, though. This would give me 160 AH, 80 AH effective at 50%.

Or I could go with an entire bank of GPL-31XT's under the lounge:

• GPL-31XT (12.9", 6.75", 9.27")

I could lay four of them in a row with dimensions of:

• 4x GPL-31XT's (51.6" wide, 6.75" deep, 9.27" high)

This would give me an estimated 600 amps, 300 amps with half cycle from the couch. However, this is 280lbs of batteries under the lounge, which is pretty concerning as to the potential impact on tongue weight.

So, I was thinking about lithium batteries -- apparently some RV'ers have had good luck with them, and they've been in use in the marine community. They're pricey, but the math does work out for them Cost Analysis of Lithium Ion Battery Systems for RVs | Technomadia

One vendor appears to be Lithionics BatteryLithionics -- there's a 200 amp hour model, which has the following weight and dimensions:

• Lithionics BDI12114 (14.7"l, 8.25"w, 11"h, 57.2lbs)

Four of these laid out in a 2x2 under the lounge would give me about 800 amp hours -- and 600 amp hours, at assumed 80% cycle -- for the same amount of weight as six GPL-31XT's. It's very costly, though.

I can go cheaper and even more custom if I wanted to go the route that the Technonomads, and hand-build my own battery bank. Apparently there are interesting issues with getting a charger that understands or works well with lithium batteries, however. I'd appreciate thoughts on this, as I am unsure if anyone else in the Airstream community has installed a Lithium battery bank.

Inverter
Reading through the forums, I found a pretty neat idea - there are inverters that can boost the output of a generator if needed. The idea is that if I get one of these inverters, I can carry a single Honda 2000i to run a single air conditioning unit as needed -- with the inverter providing the boost to start the air conditioner. And with the faster charge rate of the lithium ion's -- it makes it possible to charge the entire battery bank in a matter of a couple of hours -- which means less fuel in the end.

There are 3000W quality inverter/chargers -- but I am not sure how they'd interact with MPPT solar units or lithium ion batteries. I'd love to have one that supports boost. Any suggestions in this area?

Generator

I've already stated that I'd like to keep to one Honda 2000i. Do these Hondas support remote start?

Thank you all for taking the time to read my long-winded post! Whew.

[lewster]

Wbrown,

If you would like to discuss your energy needs on depth, please e-mail me: lew@gorge.net

Thanks!


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[DKB_SATX]

Originally Posted by wbrown

~~
Generator

I've already stated that I'd like to keep to one Honda 2000i. Do these Hondas support remote start?

~~

You'd need a LONG rope... the 2000i is pull-start. Off the top of my head, I can't think of any of the 2kw-class generators that's electric-start, that's a feature that usually comes into play on the 3kw class.

[Tyvekcat]

>",,,2014 28' International Serenity,pick it up next week"

Nice Choice in AS !
Yeah, I thought the roof was crowded and I only have one AC unit. Excellent plans you have.
In that front corner area, the Power converter is there and the subwoofer. One of my future projects is upgrade the converter and install a surge suppressor in there(or where ever I can add it).

I suggest you put a piece of cardboard under the corner seat cushion, cause that open port hole to the converter allows the cushion to fall in the hole and deform. Cardboard fixed it on ours.

Congrats on your new AS. Keep us updated to your progress.
Have a good one.

[BAB]

Do get in touch with Lew. I have a '12 28' Intl CCD which has the same roof configuration. I also have two A/C units. There is room enough for four of the AM Solar panels, you might even be able to sneak a 5th panel. I did the install myself and it went very smoothly. I've also upgraded to a 2000 Watt inverter, a higher quality converter with 3 stage charging unit, two of the Lifeline AGM's, and just replaced the Chinese automatic transfer switch that came in my trailer. A lot of what you are planning to do I've already done. I did rip out the awful L seat lounge and put in two recliners. While I lost some storage, I added a permanent cabinet over the HW heater, subwoofer, electrical panel, etc. Oh, there is room in there for a 3d AGM battery, if I ever decided to do that. My trailer is much more livable and flexible with a higher performance electrical system. Oh, I also added the Progressive voltage monitor system with the built in surge protector. If you are in a park with a ground issue, under or over voltage, it'll let you know BEFORE it connects your trailer. In the past year I've had two campgrounds that had electrical issues...both at the pedestal, I might add.

[ghaynes755]

One of the drawbacks of the flex panels is the fact that they do lay flat. Not a problem in the summer but not so good when the sun doesn't get as high in the sky. The normal panels can be tilted, if you want to make the effort to get the most power. There is an interesting video over at the gonewiththewynns.com blog (Powerful and Flexible RV Solar Panels | Gone With The Wynns) where they show them dancing on top of the flex panels from Go Power. Yeah, Lew they are dancing on top of the panels. AMSolar has some comments about flex panels that are worth reading.

Lew have you recovered yet

[lewster]

Originally Posted by ghaynes755

One of the drawbacks of the flex panels is the fact that they do lay flat. Not a problem in the summer but not so good when the sun doesn't get as high in the sky. The normal panels can be tilted, if you want to make the effort to get the most power. There is an interesting video over at the gonewiththewynns.com blog (Powerful and Flexible RV Solar Panels | Gone With The Wynns) where they show them dancing on top of the flex panels from Go Power. Yeah, Lew they are dancing on top of the panels. AMSolar has some comments about flex panels that are worth reading.

Lew have you recovered yet

I'M WAY AHEAD OF YOU! I noticed this blog right after they did their installation. Note that they are also sponsored by Go-Power. And you are very correct. If you intend to use your trailer in any other season but full-on summer, you can increase the panel output by as much as 30% simply by tilting them. Tough to do when they are glued to your roof. Not cheap either, and I dare say that by using their daisy chain connection method and basic PWM controller with no MPPT, you are in for a fair bit of voltage drop thru the system.

[wbrown]

Originally Posted by DKB_SATX

You'd need a LONG rope... the 2000i is pull-start. Off the top of my head, I can't think of any of the 2kw-class generators that's electric-start, that's a feature that usually comes into play on the 3kw class.

A Rube Goldberg contraption just unfolded in my mind -- a long cable going from the back of my truck to the Airstream -- along with a weight that is held in place as long as there's a current. When the battery goes low, the current drops, causing the weight to be released, pulling the cord!

Tada, remote generator autostart!

Originally Posted by Tyvekcat

I suggest you put a piece of cardboard under the corner seat cushion, cause that open port hole to the converter allows the cushion to fall in the hole and deform. Cardboard fixed it on ours.

An open port hole? When I looked under the cushion, it was actually covered, a hatch of sorts. Did your Airstream come with that hole open? If so, then that's probably a warranty/defective workmanship issue?

Originally Posted by BAB

Do get in touch with Lew. I have a '12 28' Intl CCD which has the same roof configuration. I also have two A/C units. There is room enough for four of the AM Solar panels, you might even be able to sneak a 5th panel. I did the install myself and it went very smoothly. I've also upgraded to a 2000 Watt inverter, a higher quality converter with 3 stage charging unit, two of the Lifeline AGM's, and just replaced the Chinese automatic transfer switch that came in my trailer.

Thank you! This is very helpful. I've gotten in touch with Lew, and we are thinking GS-135's. Do you happen to have pictures of your roof, or even better, measurements?

Originally Posted by BAB

A lot of what you are planning to do I've already done. I did rip out the awful L seat lounge and put in two recliners. While I lost some storage, I added a permanent cabinet over the HW heater, subwoofer, electrical panel, etc. Oh, there is room in there for a 3d AGM battery, if I ever decided to do that. My trailer is much more livable and flexible with a higher performance electrical system. Oh, I also added the Progressive voltage monitor system with the built in surge protector. If you are in a park with a ground issue, under or over voltage, it'll let you know BEFORE it connects your trailer. In the past year I've had two campgrounds that had electrical issues...both at the pedestal, I might add.

Thank you -- I'd hate to fry my livelihood because of faulty wiring at the pedestal. I've added the Progressive voltage monitor system to my list of items to investigate.

I take it that you did much of the installation yourself? Can you share how much of your time it took? I'm doing a cost-benefit analysis of doing it myself versus turning myself over to the capable hands of someone like lewster.

Originally Posted by ghaynes755

One of the drawbacks of the flex panels is the fact that they do lay flat. Not a problem in the summer but not so good when the sun doesn't get as high in the sky. The normal panels can be tilted, if you want to make the effort to get the most power. There is an interesting video over at the gonewiththewynns.com blog (Powerful and Flexible RV Solar Panels | Gone With The Wynns) where they show them dancing on top of the flex panels from Go Power.

Tilting sounds like a good idea, especially if I want to go to the northern latitudes, or go skiing in Colorado. Anyone rig up a mechanical tilting system yet?

I'd actually found that link and laughed, at the same time my jaw dropped. That's definitely a publicity stunt if I've ever seen one -- for both Fleetwood and Go Power!

Thanks to Lew, it looks like I'm presently inclining in the direction of:

* Multiple GS-135's from Solar AM, as many as I can squeeze on the roof.
* Blue Sky Solar Boost 50 or 3024iL
* Magnum MSH3012M

Still investigating and thinking about Lithium batteries. With the 30% solar rebate from Uncle Sam, I'd want to do the electrical work all-inclusive and roll the cost of the batteries and inverter into that, and be good for years.

Federal Residential Renewable Energy Tax Credit

[ghaynes755]

WB if you contact Airstream they can send you a roof drawing. I've used that in Visio to map out general sizing and locations. Easy to draw each of the AMSolar panel sizes and drop into place. If you already have the trailer make cardboard templates of the various panel sizes and lay them on the roof to double check against the drawings you may have created.

AMSolar has tilt bars available to allow their panels to be tilted.

Forget where I saw it but things a simple as the shadow from the AC unit falling on a panel will reduce its output a significant amount.

[BAB]

Go to the Progressive Industries website and you can check out the options. You'll want a hardwired unit with a remote. (The remote mounts wherever you choose to put it, the wiring is phone cable.) The remote will tell you everything you want to know about the power coming into your trailer, and it will provide an error code if something is amiss. I did the installation in less than 45 minutes. Basically you reroute your service cable that comes into the breaker box into the PI unit. Then you wire from the PI unit into your breaker box. Basically, it was cut a wire and rewire. I elected to put my remote close to my other info boxes...solar, Bogart Trimetric, etc.

[Photobum]

Following this one. Picking up a new FC 25FB in August and looking forward to a lot of boon docking.

[wbrown]

Originally Posted by ghaynes755

WB if you contact Airstream they can send you a roof drawing. I've used that in Visio to map out general sizing and locations. Easy to draw each of the AMSolar panel sizes and drop into place. If you already have the trailer make cardboard templates of the various panel sizes and lay them on the roof to double check against the drawings you may have created.

Awesome! I'd been working from the layout diagrams that they have on their brochureware. I sent an email to Airstream asking for a roof diagram for a 2013 28' International. And within thirty minutes, I got a detailed roofing diagram. Does anyone have a collection of these diagrams, or do we have to request them one by one?

I'm a fan of OmniGraffle on the Mac, a similar app to Visio.

Originally Posted by BAB

Go to the Progressive Industries website and you can check out the options. You'll want a hardwired unit with a remote. (The remote mounts wherever you choose to put it, the wiring is phone cable.) The remote will tell you everything you want to know about the power coming into your trailer, and it will provide an error code if something is amiss. I did the installation in less than 45 minutes. Basically you reroute your service cable that comes into the breaker box into the PI unit. Then you wire from the PI unit into your breaker box. Basically, it was cut a wire and rewire. I elected to put my remote close to my other info boxes...solar, Bogart Trimetric, etc.

Looking at the EMS-HW50C -- surge protector with voltage protection and remote display. 50 AMP model, as my Airstream has 50 AMP service, because of the second AC unit.

Looks useful. I get the feeling that there's going to be a lot of monitors, blinking lights, and doodads on the wall when done with this project. Fortunately, some of the devices support remote management and monitoring -- such as Blue Sky's UCM which bridges Ethernet and RS-485 into their IPN network. I'm half tempted to write some code, and use a touchscreen monitor or iPad to rule them all.

[lewster]

Will be getting a new set of lithium phosphate batteries in about a week. Trying a pair of 100 A/H units to see how well they replace my present Lifelines (2 GPL-6CT @ 300 A/H) which are still at 100%.

They will require some new peripheral equipment and a special charging regimen, but I'll keep you all posted on the results.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[Beach Bum]

I went through the same design process with lewster for my 30' FC in December. I have 4 AM Solar 135's with the design capacity for 2 more if I need them.

Very happy with the whole system and Lewsters install. I
got 4+ ah's February overcast day see pictures. Best I have seen is 30 ah on a sunny day in March. No tilt, no attempt to optimize AS to maximize solar.
All the data above is absolutely accurate for the exact weather conditions, trailer orientation, time and the condition of the data taker that day .

What I am experiencing is around 4ah in crappy weather and 30+ ah noon time on a sunny day with no shade.

[switz]

The 100 Watt AM Solar panels are narrow enough that we were able to place them outboard of the centerline of factory stuff on the roof (two skylights, two air conditioners, fantastic fan...). We have four on each side for a total of 800 watts. These feed into a TriStar 60 MPPT charge controller and then into four Lifeline 6CT 6Vdcx 300 amp-hour batteries mounted on the front of the trailer in a new stainless steel battery box. Power from the batteries is processed through a Magnum MS-2800 inverter. All the factory outlets plus ones we added are powered by the Magnum system.

We have the factory 50 amp service and installed a new primary electric panel to drop the front air conditioner and the AC power to the water heater and refrigerator when not on shore power as the Magnum inverters with dual contractors are only rated 30 amps. We put in a 240 volt 30 amp breaker to send shore power to the Magnum and then to all other appliances in the trailer. Note that a Magnum 2800 has the power to spool up the rear Air Conditioner from the batteries.

Our original battery box houses the hydraulic disc brake pump and it's controller for the trailer disc brakes.

I would think your installer could get three on each side of a 28' trailer. We did put a lower vent cap on the plumbing vent which is under one panel.

[jacksway1]

This is a very interesting topic. Thanks.

[rp709]

Beech bum, do you have pics of the roof? What solar panels did you install. I'm planning to buy a 2015 FC 30 soon. Thanks, Ron

[Beach Bum]

Ron,


This is the best picture I have and it was taken in the middle of the install .....so that wire you see hanging there on the forward panel was properly run and secured to the pannel later.

I have have used the system for about 100 camping days and am very happy with the performance and installation.

I don't know what if any issues the new roof line for ducted AC may cause. Also if someone wants to drill any holes in your roof to install run do not walk away !!!!!!!!!!!! The only drilling and cutting needed is on the inside to run the cables and mount the equipment and displays.

Benn

[rp709]

Benn, that is a killer install! Thanks for the pics. Do you know where Airstream mounts the solar charge control panel on a factory solar install? Will this location be available for an after market install using the solar prewire that is standard? I only plan about 200 watts and factory wire gauge should be big enough. I'm planning to order a FC 30 and will select options. By the way, Colonial has an Int'l 30 with solar, and pics of the roof, and it has panels mounted similar to yours. Thanks, Ron

[Beach Bum]

Ron,

Thanks. Sorry not much help on the AS wiring. I'm not sure where AS puts the controller. I did not get the solar pkg from AS. Also, I did not use any of the AS solar pre wire too wimpy for 800w set up. I installed the solar control panel on the bulkhead behind the dinette. If you are ordering new you may want to consider a complete after market pkg so you get exactly what you want. You can call the folks at AM solar they are a wealth of info.
Benn