keys to upfitting lithium/solar/inverter to an older coach

[fullofdays]

looking at saving a lot of money purchasing a 2-3 year old coach and am wanting to delete the generator and run solar/lithium/underhood generator. What are the keys to upfitting an older coach with a modern solar array/lithium/inverter, etc? Are there accessories on older coaches that will not work efficiently with a generatorless setup? Any advice would be helpful. For folks that have gone this route, whatcost considerations or other factors will make for an effective upfit? Is an underhood generator/voltstart a good path to upfit on a 2-3 year old coach? I'd love to know if anyone has gone this route and what they learned.

cheers,

[BBQ]

.

There are no ready made off the shelf underhood generator kits.
Not yet.


If you want to go all electric,
you will probably need $5,000 to $10,000 worth of batteries.

[gregmchugh]

Originally Posted by fullofdays

looking at saving a lot of money purchasing a 2-3 year old coach and am wanting to delete the generator and run solar/lithium/underhood generator. What are the keys to upfitting an older coach with a modern solar array/lithium/inverter, etc? Are there accessories on older coaches that will not work efficiently with a generatorless setup? Any advice would be helpful. For folks that have gone this route, whatcost considerations or other factors will make for an effective upfit? Is an underhood generator/voltstart a good path to upfit on a 2-3 year old coach? I'd love to know if anyone has gone this route and what they learned.

cheers,

It all depends on what loads you want to be able to power from the system.

The inverter will need to be sized to handle your maximum 120 volt AC loads.

The size of your lithium battery bank will be driven by the length of time you want to be able to power your load profile on a cloudy winter days with minimum solar charging before running the engine generator to recharge the batteries.

The size of your solar panels will be driven by your load profile and how much you want to avoid running the engine generator to charge batteries.

At the extreme, if you want to run air conditioning off the battery bank without running the engine generator continuously, doing something like Voltstart, the size and cost of the battery bank can be expensive. All depends on how long you plan to run the air conditioning and how often you want the engine generator to cycle on for some period of time to recharge the batteries. Solar is not significant in the air conditioning scenario.

In terms of mods you will need new wiring for the larger inverter, engine generator, solar, and battery bank. Inverter/charger, engine generator, solar panels and controller, and the most expensive item the lithium battery bank with a battery management system. If you plan to camp in cold weather you need to address the possible need for battery heaters depending on where you plan to locate the lithium battery bank.

Bottom line, not a cheap upgrade but price varies considerably depending on the size of the battery bank and the loads.

For the engine generator look at a Nations aux high amp alternator kit with a Balmar voltage regulator.

[booster]

Almost all of the 2-3 year old class B's will be similar in starting point, I think, which is to say you have rip out all that is there and start over.

As was mentioned, you need to first determine what you want to accomplish, both wants and needs, so you can chose the appropriate components and capacities.

Several of us here have opted to not try to run the air conditioning off the batteries, although most would be able to for short periods (pet cooling while shopping, etc). This decision makes the system significantly more simple in design and use, and in most cases makes an autostart unnecessary. Some of us chose to stay with AGM batteries, at least for now, with the the non air conditioner systems, but I think that decision is separate from the rest of the evaluation unless you decide you need to run the AC off batteries and need to have an autostart to keep it going for long hours, as then you would need lithium and autostart.

I think that all of Roadtrek's misadventures in trying to get these new style systems to work right indicates that it is not necessarily easy to do properly. It is also not cheap.

Since you essentially wind up starting from scratch in a retrofit, you may be better off to read the threads on full DIY new conversions on this site. They are full of details about decision making, parts, and how to do.

[markopolo]

Excellent replies! I started typing this and now see those replies but will post this anyway (apologies in advance for any duplication).

A lot of research and planning is core of the project.

The DIY projects you'll find on this forum fall into several categories:
1. Doing something unique - it's just not available commercially.
2. DIY to use all the best components available - again typically not available in a commercial package.
3. Saving money - usually through DIY labor or finding items on sale.
4. Doing it well - when it is available commercially but you want to make sure the job meets your standards to avoid disappointment.

#3 saving money doesn't necessarily go along with #'s 1,2 & 4.

IMO - you need a good understanding of the feature set you want at project's end prior to starting and you need some technical knowledge, both mechanical and electrical. You need to understand what terms like voltage drop, ampacity, resistance, PWM, MPPT, etc. all mean.

Again, in my opinion, the project would start with the choice of batteries. Batteries can have specific requirements so all of the other components follow from there to meet those specific requirements.

Read through Avanti's, Booster's, Ptourin's, Mojoman's posts as a start to see what items they chose. Many other member have done upgrades along these lines so my apologies to anyone I didn't mention. Avanti & Booster chose AGM batteries & Ptourin & Mojoman chose lithium batteries. IIRC Avanti might be the only one in that group with dual alternators.

In case you are not aware most Underhood Generators are actually just a DC alternator (requires running the van engine) combined with an inverter. I believe Great West Vans had just started to use an actual under-the-hood AC Generator prior to going out of business. It also would require running the van engine.

[gregmchugh]

As I recall, Roadtrek toyed with a 120v AC aux engine generator at one point in their evolution to the current configuration but I don't think they ever installed one in a production vehicle, at least I never heard of one...

[markopolo]

Good memory. The Wendland Etrek promo video from Sept 2012 showed what looked to be a Fabco Power-Mite AC generator. It wasn't shown installed but you'd have to guess that they at least tried it at some point else it would have been just a prop for the video.

[fullofdays]

Lots of good information! Thanks all for sharing your responses. Looks like a complex project and not something I'd want to tackle on my own which brings up the cost significantly.

I looked at an efoy fuel cell for my off road conqueror conquest trailer a few years ago. The technology is amazing and there was a company stateside that made some significant breakthroughs in off the grid power in 2013 but they were quickly acquired by the government and went dark with their product for government-only use.

Lots of amazing tech that poor civilians don't get the luxury of enjoying... At least anytime soon (i.e. gps and sat nav from the last decade)

[gregmchugh]

Originally Posted by markopolo

Good memory. The Wendland Etrek promo video from Sept 2012 showed what looked to be a Fabco Power-Mite AC generator. It wasn't shown installed but you'd have to guess that they at least tried it at some point else it would have been just a prop for the video.

My brain seems to retain trivial technical info forever but I can't remember more than 4 things on a shopping list or remember anything short term. Getting old has its issues...

[booster]

Originally Posted by gregmchugh

My brain seems to retain trivial technical info forever but I can't remember more than 4 things on a shopping list or remember anything short term. Getting old has its issues...

"EATS" Engineer's Associative Thinking Syndrome

They implant it in you someplace around your junior year.

How do you get all the way up to 4 items on the list?

[avanti]

Honestly, if you stay a step or two back from the bleeding edge, building a pretty capable electrical system is neither all that complex nor all that expensive. I picked the system I did because it appeared to be in the sweet spot along both of these dimensions. Here is a very realistic budget:

2800 watt inverter & associated bits: $2000
Nations Alternator 270 amp second alternator (compete kit): $2000
110Ah AGM Group 31 battery: $250 x 4 = $1000
Cables, connectors, switches, battery monitor: $1000

Nothing at all exotic about such a system, and I have rounded up with all prices. $6K is not a lot of money by b-van standards, and although it doesn't quite get you an ARV-class system, it far exceeds anything you will find on an older van. You can add solar later, but this is only important if you store your vehicle outdoors and don't have access to shore power.

[Davydd]

Originally Posted by BBQ

.

There are no ready made off the shelf underhood generator kits.
Not yet.


If you want to go all electric,
you will probably need $5,000 to $10,000 worth of batteries.

Avanti installed his own Nations second alternator with Balmar regulator in a Great West Van Legend Sprinter. It is sold as a kit. The alternator is a considerable investment and probably $2,000+ once you do all your wiring, brackets, etc. It is still less expensive than an Onan generator, plus space saving and weight saving.

You can get 400ah lithium ion battery packs for for less than $3,000. Google Elite Power Solutions. 400ah will do most everything you need for off grid and more just ups the time you can spend. The second alternator's faster charging makes it feasible to get by with less battery and solar, IMO.

The other key ingredient is a large capacity pure sine wave inverter/charger to power all you VAC appliances off the batteries. We have an Outback 2800w.

Auto start or Voltstart as Roadtrek calls their system lessens in need with the addition of more battery. We never use our Advanced RV Autogen system with 800ah of batteries. We never sit long enough and the second alternator does most all of the charging. Keyless starting is important for those temporary stops. That can be done manually with a key fob.

With more battery capacity, solar becomes less significant. Solar becomes like sprinkle candy on a cookie.

Air conditioning is always the Holy Grail of desire. Overnight can be done but at a ridiculous effort. Google Solar Womp if you like that kind of challenge. Smarter is to open you van with screening to equalize inside temperature with the outside and utilize fan air movement. Stay away from hot and humid travel as much as possible. I think smart planning your trips that way is easy peasy if you live in a northern climate or full time. Maybe not if you live in the south. When things get really hot and humid, there are many campgrounds with shore power.

Lithium ion batteries need cold weather protection. If you live and camp in temperatures that never get down below mid 20s it is probably not a concern. Inexpensive electric heating pads can take care of it. Engineering automatic sensing and operation may take more skill to solve on and off grid.

Lithium ion battery charge controlling from multiple sources of power is beyond my expertise but it would be a concern. Advanced RV worked it out for me and I remain ignorant to how it all works. I just know what is taking place by observation through detailed real time fairly precise readouts on a Silverleaf coach controller.

Our bottom line is we live off-grid identically as if we were plugged into shore power without concern for energy conservation. We have 120VAC available all the time that powers everything. We brew coffee in a Keurig while stopping to fill our diesel tank at a service station for instance.

[booster]

Originally Posted by avanti

Honestly, if you stay a step or two back from the bleeding edge, building a pretty capable electrical system is neither all that complex nor all that expensive. I picked the system I did because it appeared to be in the sweet spot along both of these dimensions. Here is a very realistic budget:

2800 watt inverter & associated bits: $2000
Nations Alternator 270 amp second alternator (compete kit): $2000
110Ah AGM Group 31 battery: $250 x 4 = $1000
Cables, connectors, switches, battery monitor: $1000

Nothing at all exotic about such a system, and I have rounded up with all prices. $6K is not a lot of money by b-van standards, and although it doesn't quite get you an ARV-class system, it far exceeds anything you will find on an older van. You can add solar later, but this is only important if you store your vehicle outdoors and don't have access to shore power.

Any reason you chose the 12v group 31 batteries instead of the 6v golf cart ones?

I totally agree with everything Avanti said. At this technology level, off the shelf parts can be put together to do a good job. Ours is similar to his, except with a 2000 watt psw inverter and we run just an oversized single alternator of 250 amps.

[gregmchugh]

Davydd mentioned the Elite Power lithium battery system. I have posted this before but it is a good overview in a set of blog posts on AGM vs lithium and an Elite Power lithium installation...

The Big “Beastly” Solar/Battery Upgrade Part I – Why? – Wheeling It

[avanti]

Originally Posted by booster

Any reason you chose the 12v group 31 batteries instead of the 6v golf cart ones?

Yes, but it isn't too profound:
My van came with 2 such batteries, so I just bought two more to match.

[fullofdays]

Originally Posted by Davydd

Avanti installed his own Nations second alternator with Balmar regulator in a Great West Van Legend Sprinter. It is sold as a kit. The alternator is a considerable investment and probably $2,000+ once you do all your wiring, brackets, etc. It is still less expensive than an Onan generator, plus space saving and weight saving.

Is there a similar underhood kit for promaster vans or will I be limited to sprinter diesels for underhood generator?

[gregmchugh]

Originally Posted by fullofdays

Is there a similar underhood kit for promaster vans or will I be limited to sprinter diesels for underhood generator?

Nations Alternator has a kit for the standard gas engine in the Promaster which I believe is the alternator Roadtrek is using in the Zion engine generator.

[SiennaGuy]

Originally Posted by fullofdays

I looked at an efoy fuel cell for my off road conqueror conquest trailer a few years ago. The technology is amazing and there was a company stateside that made some significant breakthroughs in off the grid power in 2013 but they were quickly acquired by the government and went dark with their product for government-only use.

Lots of amazing tech that poor civilians don't get the luxury of enjoying... At least anytime soon (i.e. gps and sat nav from the last decade)

Before we go off into government conspiracy theories about US fuel cells, here's a list of the top 200 companies manufacturing or using fuel cells.
Hydrogen and Fuel Cell Archives - Index

[SiennaGuy]

The Sprinter Store in Tualatin, Oregon carries an auxiliary alternator kit that comes with a regulator. The site doesn't say which brand(s) they offer. The description, however, includes this unclear sentence:

"It can not be installed if your Sprinter has an auxiliary A/C system."

I'm assuming that they mean an auxiliary A/C system that runs off the engine, not the RV-type of AC that is separate from the engine, but I don't know. It's worth a call to them.
http://sprinterstore.com/product-cat...inter-aux-alt/

[avanti]

Originally Posted by SiennaGuy

The Sprinter Store in Tualatin, Oregon carries an auxiliary alternator kit that comes with a regulator. The site doesn't say which brand(s) they offer. The description, however, includes this unclear sentence:

"It can not be installed if your Sprinter has an auxiliary A/C system."

I'm assuming that they mean an auxiliary A/C system that runs off the engine, not the RV-type of AC that is separate from the engine, but I don't know. It's worth a call to them.
Sprinter Aux Alt Archives | Sprinter Store

That kit is essentially the same thing sold by Nations Alternator that I installed. There is some ambiguity, since a picture on their website shows a Powermate Wrangler inverter, whereas the user Gamma1966 over at Sprinter Source reports that they installed the full Nations setup on his van:
Sprinter-Forum - View Single Post - Maybe add-on alternator and not solar?
In any case, they both use the excellent Balmar regulator/charger.

The "can't use with aux A/C" thing refers to the second A/C compressor that you can buy as a Mercedes option--it uses the same aux takeoff position as the Nations kit.