Need advice for new system

I'm building an off-grid cabin and would like some advice and recommendations for a new solar/battery/generator system that I would use to power the home. I have a lot of questions so thanks in advance.
First off, I had a solar consultant tell me that with the regular usage in my primary house, it would require a 6kw solar system to basically cover all my usage. However, I use Air conditioning, etc frequently and other high draw devices and non-energy-efficient devices which I would not use in the cabin. I am, however, planning on installing 6kw worth of panels on the cabin, as its partially obstructed with tall trees and I want to install a bit more to compensate for partial shade.
The cabin will use propane for the following devices:
fridge
furnace/boiler
stove/oven
water heater
generator for battery bank charging (autostart when below threshold)
For the panels, I'm not sure what type or brand. Just 6kw worth on the south facing roof mostly.
For the charger/inverter, I was thinking the schneider conext XW+ 48v 6.8kw
For the battery bank, I just discovered a new type called "lithium iron phosphate" that appears to be perfect for solar. The one I was considering is the 48v 400 ah Iron Edison. It is expensive but looks like its built to last a very long time.
For the generator, I'm not sure. I see a 15kw Generac Ecogen, that appears it might be good for off grid, however I heard reliability issues about the brand. My priorities with the generator are reliability, minimal maintenance, and quietness.
First question is, does this system sound about right? Any major problems or incompatibilities with this equipment? What about the generator? Any advice for other better or more reliable models? And will the battery work well with the 48v XW inverter? Basically would like feedback or advice on this plan from the experts. Thanks!
First off, I had a solar consultant tell me that with the regular usage in my primary house, it would require a 6kw solar system to basically cover all my usage. However, I use Air conditioning, etc frequently and other high draw devices and non-energy-efficient devices which I would not use in the cabin. I am, however, planning on installing 6kw worth of panels on the cabin, as its partially obstructed with tall trees and I want to install a bit more to compensate for partial shade.
The cabin will use propane for the following devices:
fridge
furnace/boiler
stove/oven
water heater
generator for battery bank charging (autostart when below threshold)
For the panels, I'm not sure what type or brand. Just 6kw worth on the south facing roof mostly.
For the charger/inverter, I was thinking the schneider conext XW+ 48v 6.8kw
For the battery bank, I just discovered a new type called "lithium iron phosphate" that appears to be perfect for solar. The one I was considering is the 48v 400 ah Iron Edison. It is expensive but looks like its built to last a very long time.
For the generator, I'm not sure. I see a 15kw Generac Ecogen, that appears it might be good for off grid, however I heard reliability issues about the brand. My priorities with the generator are reliability, minimal maintenance, and quietness.
First question is, does this system sound about right? Any major problems or incompatibilities with this equipment? What about the generator? Any advice for other better or more reliable models? And will the battery work well with the 48v XW inverter? Basically would like feedback or advice on this plan from the experts. Thanks!
Comments
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
Why drop the propane fridge? I'm planning on purchasing a brand new, several hundred gallon propane tank which will last for decades. Is your old small propane tank the only reason or do you have other reasons for advising me against it?
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
Cabin is in northern Wisconsin its only seasonal.
Regarding the lead acid batteries, my last system used those and I'm not really happy with the experience. They require maintenance, extra precautions regarding the off-gassing hydrogen, rapidly degrade in capacity and have to be replaced every few years. It just seems like the only thing they got going for them is the initial cost but that is deceiving. The reason I'm considering the Iron Edison 400ah 48v Lithium Iron Phosphate is that, it doesn't off-gas, it doesn't require maintenance.. "100% Maintenance Free" according to the company....so as far as the comment about needing to know about proper care and feeding of those batteries, what would that be, for this particular model, that appears to be designed for ease of use and comes with a 10 year warranty. "The integrated Battery Management System (BMS) monitors and regulates each cell in the battery bank to provide perfectly balanced charging and discharging while guarding against over-charge, over-discharge and thermal overrun situations."
For the battery bank, I just discovered a new type called "lithium iron phosphate" that appears to be perfect for solar. The one I was considering is the 48v 400 ah Iron Edison. It is expensive but looks like its built to last a very long time.
Read this thread, very informative and detailed https://forum.solar-electric.com/discussion/comment/379405#Comment_379405
Refrigerator wise, either DC or AC over propane
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Any shading is bad, so I'd recommend trimming or removing the trees so the whole array sees full sun until whenever you leave in fall. Even minor shading from a few branches can cut output to near nothing. Trimming enough for long winter shadows may be impractical, so I'd assume the array will be in shade and snow covered all winter. As such, the system should be shut down completely in fall.
Lithium will be okay sitting over the winter, but can't be charged in freezing temps. Depending on the length of your season, flooded self-discharge could be an issue, needing a float or occasional charge. AGM or lithium may make more sense for your application.
If you are getting a big propane tank and delivery is available, a propane generator may be a good choice. 15kw may be a bit big though. My 4kw diesel goes mostly unused until fall. If I was to replace it, I'd likely look for something ~7-8kw (I have roughly similar size bank as what you're considering. Fuel stability could be an issue, especially with gas and to a lesser extent with diesel.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
As well as making a trip out in January to clear, I also added some completely vertical panels with the sole purpose of floating the system to offset self-discharge and charge controller consumption.
I assume you'll be using glycol in the hydronic loops. I've never seen a heating system that can't fail. Do you have a local contact who can check on things over the winter?
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
I'll be able to monitor temperature etc remotely with smart thermostat and cameras.
With lithium, they might be okay sitting discharged in the cold, which would be a big pro for using them. Personally, I'd want to be sure there was no way they'd charge in freezing temps though, not just by assuming the heat works, but by either/both of the charge controller and/or BMS preventing it.
I can think of way too many ways for things to go pear shaped with auto generator start, especially unattended, to risk it. Lots of people do though, apparently without problems.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter