Requesting your thoughts on Montana Super Solarflex system

[ncognet0]

Im pondering buying a new coach and am intrigued by the new Super Solar system by Keystone Montana. I really like the idea and concept that its 100% powered by the sun. They even claim it can run the AC units/microwave/heater... everything. My dilemma is this, the last "newest upgrade thing" I purchased was a tankless hot water heater in my old 5th wheel and hated it. I had to run several gallons of water through it before it got hot, that don't work for dry camping. That being said is the 15 K worth it for this off grid solar system? Anyone have it? Thoughts?

[ncognet0]

I went with the non solar, I hated to be the test dummy. Ive done that and was disappointed with a tankless hot water heater. If the solar turns out good ill trade mine in in a few years.

[kowbra]

ncognet0 wrote:
Thank you, i found out today the batteries are only waranteed for 5 years. then it's at least 7k to replace them. my luck they would last 5 years and one day.

I am looking at this package also... well, there sure is some good information and some misinformation on this thread, that's for sure.

The batteries are unique -both for size (255ah) and for the built in charge heaters. They are made by Dragonfly, the parent of Battleborn. I read good things in general about the brand and their business practices. It does surprise me the warranty is only 5 years; I will see if I can confirm that as I thought it was 10 years.

As to value; well each must decide. But, if you think this is just a bunch of solar panels and a couple of lithium batteries that any DIY can throw together... I think a little more research would reveal it is far more than that.

Running the whole coach, including one AC never mind both, is not trivial and was not possible a few years ago. Neither was the level of power management at the level provided here.
I would not feel comfortable doing a DIY installation of this scale and getting it all right, and I've done a couple of solar installs on prior units.

Also, add the cost and weight of some of the other suggested solutions, especially a combination of solar, lithium and an onboard generator. When I did that math, it was very close to the selling price of the Super Solar package.

One thing not noted above is how many jugs of propane needed to run dual ACs; many built in generators will go through a 40lb jug in 8 hours or less when loaded. So, let's not pretend the issue is as black and white as some make it out to be. Heavy use of the factory AC units while boondocking requires a lot of energy, and all energy comes at a cost... dollars to buy, dollars to maintain, dollars to run, etc. Solar wins on some of those and loses on others (different but the same with generators)

IMHO and YMMV, of course.
As for me, I'm nervous being an early adopter, but strongly considering it...

Brad

[ncognet0]

Thank you, i found out today the batteries are only waranteed for 5 years. then it's at least 7k to replace them. my luck they would last 5 years and one day.

[n0arp]

You would be better off spending $20K on your own setup. 1000W of solar and 510AH of batteries won't run your AC for any length of time, and if you attempt it, you won't be able to refill your bank in a single day.

My two Dometic rooftop AC units pulled 2.7kW combined when actively cooling (compressors on, fans on high) my 39' Alpine. That would drain a 12V/510AH battery bank in around two hours, and 1000W of solar won't quite fill that bank in a day under ideal conditions with no load. If the compressors only run 50% of the time, you might get four hours. The math used for these figures:

• 12V * 510AH = 6120Wh, 6120Wh / 2700W = 2.26h, assuming no other loads
  
• 1000W * 6 solar hours = 6000W, which is less than the 6120Wh size of the bank
  
• You can generally expect 5-6 solar hours per day, depending on location and other factors
  
• I did have someone tell me that two of those Mach units pull 2400W together, but haven't personally verified -- that doesn't buy that much extra time
  

You could, of course, only run one AC unit. Indefinite AC on solar does not work out with current solar technology and rooftop RV AC units, but can be done with mini-splits (that's a whole separate and far more major project). There simply isn't enough real estate on RV roofs to make the math work, and with more real estate, you need more cooling, which requires more energy, so the issue remains as you size up.

You can purchase much more solar and battery than they are selling for $20K and have better quality components.

It's nice to see more than the conventional 200W systems, but this isn't enough to be self sufficient with all systems functioning on demand, and certainly doesn't justify the cost.

We have 2925kW of solar and a 48V battery bank that would be the equivalent of 1800AH@12V. Even with that, we had to move to mini-split AC units to be able to set the thermostat and forget about it. They use 1/3rd of the energy of the units they replaced, and perform a better job.

For what it's worth, we don't plug in, and only run the generator a few hours a month at most. We run everything as we please without worrying about consumption unless there are consecutive cloudy days. When those occur, we just make sure we have LP for the genset which is integrated to the rest of the system and starts automatically when certain conditions are met.

[Tom_M1]

Here's a link to the solar setup. Doesn't say much more than in the main overview:
https://www.youtube.com/watch?v=apeWU8CN_eU

[JKJavelin]

Here's a biased review of the Montana Legacy with that solar package. He doesn't show a whole lot of the details about the solar, says he will in another video.
https://youtu.be/oEnvJR0LBlg

Nice rig.

[2oldman]

The power required for air-conditioner start-up is Achilles’ heel of advanced energy systems

Not really. A sufficient complement of batteries and a big enough inverter will start one easily. It's on generators where you have the startup problem. Generators cannot surge like an inverter with enough batteries.

The achilles' heel is keeping one running for 8 hours.

[Tom_M1]

Only $19,500.
From their website:

"Super SolarFlex™ package includes:

JABONI POWER PRODUCTS SOLAR PANELS

1,000+ watts of solar collection

60 AMP OF MPPT SOLAR CHARGING CAPABILITY

MPPT (Maximum Power Point Tracking) technology maximizes power under all conditions, collecting more energy from the solar array than standard PWM (Pulse Wave Modulation) systems

DRAGONFLY ENERGY™ GC3 LIFEPO4 LITHIUM ION BATTERIES

Two best-in-class lithium ion batteries delivering a combined 510 amp hours of storage. Lithium ion batteries last longer, provide 2-3X more usable power, and are 80% lighter than lead acid batteries. With Super SolarFlexTM, owners have the option to add up to 510 AH of additional storage post-purchase.
Designed and Assembled in the USA 3000-5000 cycles
Built in Battery Management System (BMS) monitors all operating conditions of the batteries to ensure they operate properly
Internal heating system allows cold temp charging at below freezing temperatures, enabling the battery to operate in any environment

FULLY ELECTRIFIED COACH WITH 3,000W MAGNUM HYBRID INVERTER CHARGER

Powers every outlet, every appliance, every system in your Montana
Dual, 50AMP pass-through transfer switch power what you want when you want, regardless of the available energy source (solar or shore)
Directs shore power to charge batteries until electricity is needed in the coach, then diverts current automatically

PRECISION CIRCUITS™ ENERGY MANAGEMENT SYSTEM

State-of-the-art load management system.
Prevents inverter overload by monitoring energy consumption and temporarily disabling non-critical circuits

ADDITIONAL SYSTEM SAFEGUARD

Precision Circuits™ Battery Guardian provides a second level of protection by disabling 12V circuits until adequate battery charge is achieved

VICTRON BMV-712 WITH VICTRON CONNECT

Battery load monitor and easy-to-use smart phone app provides real-time monitoring and reduces energy anxiety

Coleman-Mach Powersaver A/C with integrated soft-start

The power required for air-conditioner start-up is Achilles’ heel of advanced energy systems, so Keystone’s engineering teamed up with Airxcel to design a soft-start air conditioner for Super SolarFlex™. This model is the only UL-listed soft start system on the market today. Additionally, the Coleman-Mach Powersaver series delivers maximum cooling and uses up to 40% less energy than conventional RV air conditioners.

Super SolarFlex™ is available as an option on every Montana model, and has a MSRP of $19,500. If you have questions about this package, feel free to reach out to Key Connect Product Advisor or contact your local Montana dealer."

[2oldman]

ncognet0 wrote:
Ive thought about buying a small Honda generator solely for the purpose of charging the batteries..

That's the way to do it.

Solar is wonderful..if... you have enough, and enough battery. It takes a lot of battery capacity and a big inverter to run microwaves and toasters.

[ncognet0]

Thank you and my thoughts are telling me the same, I love the idea of full solar it would be like being plugged in with the exception of a sewer dump.. We also have cloudy days. Ive thought about buying a small Honda generator solely for the purpose of charging the batteries. My gut feeling agrees with you though.

[2oldman]

ncognet0 wrote:
I really like the idea and concept that its 100% powered by the sun. They even claim it can run the AC units/microwave/heater... everything.

They can claim whatever they want, but from my chair it's nonsense.

The sun doesn't shine all the time, and solar doesn't "run" things unless you have a backyard full of it. AC can run on batteries, for a short time, depending on the size of the unit.