I have the feeling you are mying things up with Victron gear.
Please provide the parameter of your usage:
AC max peak laod → to be covered by MP2/Quatro. You wrote about 3-4 kW.
Base laod → can be covered by MP2 or AC-PV
intended micro grif type: 120V split-phase
manageable laods, e.g. an electric vehicle or heat pump with storage to use whne there is much AC-PV
daily consumption
location: where in alaska (3 hrs sun during winter)
location of panels and direction: ground mounted, varaible tild 20-80 degree and you have a shed
With the parameters I remeber (4kW peak, 120V splitphase), I would recommend
2x MP2 3k 120V split phase
4kWp AC-PV vertical on the shed, maybe over panel but limit inverter to 3kWp per phase
DC-PV (RS450 or MPPT) on the ground mounted tild array, as much as you like
battery: double/tripple check how many EG4 can be stacekd to together. Else go for other supported batteries (not Pylontech) or DIY with EVE MB56 cells (628AH) and a known BMS like PACE200, JK, Seplos, Batrium…
See Battery Compatibility [Victron Energy]
Other good source is YouTube “Offgrid Garage”
With DIY you can extend anytime, though start small. Commercial solution often do not accept extension of battery later than one year after setup.
I assume the system is somehow life critical. Though I would prefer several smaller compoenents, like 4x RS450 instead of one big EG4 in case one component fails.
For single points of failure, just have a spare, like Cerbo GX, MP2.
In harsh environments, beeing able to fix things and not need to wait for service is critical.
What is the reason you want use generator as less as possible? what is the price of Diesel at your location (inluding transport)?
A 50 kWp PV system for 5kWh daily consuption is by far over sized. Or you have to pay every ml of Disel by one g of gold…
Maybe a reox flow battery or a H2 storage with fuel cell long term storage companion might be your needed setup.
You wrote using a wood stove. can you source wood cheap and local?
Have you though about a wood gasiver and use the wood gas for heat and a generator and also use the waste heat from the generator for heating?
So if you start again with your pure needs and not with an amount of specific PV panels and other specific components, we might be able to help better.
I am very happy I could selct what I want and have many DIY compoents as I have full access and can paramterize to my needs.
With regards to the batteries, my current selection are Coremax 48v 400ah LiFePo4 20 kwh battery storage System. I’m not 100% committed to those. I would go with another brand that are artic rated for extreme cold. Any recommendations on cold rated batteries ?
LFP chemistry does not allow to charge below 0 degree Celsius. You can get batteries with build in heat mats like Gobel, NKOn and others.
It depends on your real temperatures. A 20W heat mat might not suite -40 degree C or what you expect.
I would plan two things:
Isolate the room or battery cabinet
Plan to heat your batteries from generator waste heat in case of emergency. You need to get your system running again after a failure
The EG4 20kWh is a stack of 4x5kWh batteries. Each has a BMS. Find out the maximum amount of stackable BMS. Most are limited to 15 or 16 batteries. This would limit the EG4 to 80kEh. But haven’t deep dived into that model.
Each BMS takes some energy. Having many BMS can eat up you solar gain during winter. Same applies to by far oversized idling MP2.
It looks like a high quality package though and I’ll look more into EG4.
If Victron offered a MultiPlus II inverter with 15,000kw to 20,000kw of continuous input/output 120V for North America with the low idle feature that would be a top candidate for inverters for me. But, they don’t, they offer the Quattro at around 10,000kw and has a very high idle draw. I won’t be buying the Quattro inverter.
I would also be more interested in Victron if the separate MPPT controllers they offered were more powerful per unit per kw. It would be great if they had a 20,000kw MPPT controller instead of just smaller ones at 1.45kw to 5.80kw. Stacking two 20,000kw MPPT controllers would be fine for me.
The Victron SmartSolar MPPT 250/100-Tr VE.Can is good, I just don’t want to have to buy 10 to 20 of them.
you know, I been going through ChatGP with looking things up and sometimes I am getting conflicting info from it and it contradicts itself. It’s been helpful for many things but it misses and leaves things out on other things.
For batteries, I’m looking for the best deal, the most kwh for the cheapest price, looking for a battery stack bundle of 100kwh to 150kwh for $15,000 or below.
JM Batteries 48v 400ah LiFePo4 20 kwh battery: $2,093. 7 140kwh for $14,651.
The Coremax 48v 400ah LiFePo4 20 kwh battery storage System: $2,500. 6 Coremax storage systems of 120kwh is $15,000.
The EG4 20kwh system: $2,700 with the BMS fuse with each unit. $16,200.
You should start reading specifications and asking support for missing information.
I am working in L2 support for IoT. We gave up using AI as it was not precise enough to give meaningful technical advise to our foeld technicians.
A general LLM will not help you to design your system.
All limitations, obstacle and design guidelines have been given in this thread.
I’ve been doing some comparing of different inverters (Sol-Ark, EG4, Victron) with idle draw. The Victron MultiPlus has a lower idle draw compared to the others including the Victron Quattro. I’m leaning towards the Victron MultiPlus-II 48/5000/70-95 120V ( PMP482505110 ).
Some of the EG4 and Sol-Ark inverters have idle draws that average roughly around 3.5khw daily. They really need to work on that and see if they can get it down to something closer to 0.3kwh per day at most.
Victron Quattro has two AC inputs and two toroidal transformers, which means it contains more electronic components and results in higher self-consumption.
As I understand, you don’t have a grid connection at all, so you don’t need two AC inputs — one is enough for your generator.
Could you please explain why you need 3 MultiPlus-II 48/5000 120V instead of 2?
The 2× MultiPlus‑II 48/5000/70‑95 120V model is almost twice as large as what you need based on your consumption.
Victron devices are very reliable, so you don’t need an extra unit for quick replacement in case one fails. Even if that happens, you will still have the second unit.
As I know, the default 5‑year warranty can be extended to 10 years.
In my opinion, it’s better to put that extra money into a bank deposit.
I’m going to need the Victron setup to communicate with the battery and diesel generator.
Is the Victron Cerbo GX MK2 able to communicate and is it compatible with the JM 48V 51.2V 30kwh JM-M-51.2V 600AH battery BMS ?
The diesel generator is a Equipment Source Inc (ESI Alaska) KPG-06 Arctic Re-Air enclosure diesel generator AGS control system is designed for cold-climate operation, including engine block heater control and auto-start functionality.
The JM battery’s BMS has CAN2.0/RS485 (customizable). Is that compatible with the Cerbo’s CANbus-compatible BMS CANopen or VE.Can VE.Can 1 and VE.Can 2 protocol ?
If not, could I have a technician use Raspberry Pi dbus-serialbattery + Victron SmartShunt or Victron Digital Multi Control (DMC) to get the Victron/JM battery/diesel generator’s auto-start to all communicate in sync ?
Just checked the JM official website, and there is no documentation (datasheet/user manual/cell type/bms) for the battery. Batter to avoid such brands.
I’d like to have installed an outlet for EV charging and engine block heater for diesel truck on an off grid property, both an indoor outlet inside the garage / barn and right outside…
Will the Victron setup below be sufficient / capable of those demands?
2× MultiPlus‑II 48/5000/70‑95 120V
10x Victron SmartSolar MPPT 250/100-Tr VE.Can
Victron Energy Cerbo GX MK2
48.3kw solar array
160kwh total battery storage
Anything I need to be worried about or cognizant of ?
