Autarkes System auf dem boot

Interesting setup — this mirrors something I've been thinking through for a potential boat project alongside my shepherd's hut build.

Running a 48V LiFePO4 bank on a vessel raises some points worth discussing here, particularly around the MPPT sizing when you're pushing 3kW+ of panels.

My hut currently runs a Victron SmartSolar 150/45 feeding a 24V Fogstar Drift 200Ah bank, which is manageable. But scale that up to 48V with six panels and suddenly your charge controller selection becomes critical — you're potentially looking at a 150/100 or even the 250/100 depending on your string configuration and whether you're wiring in series, parallel, or a hybrid arrangement.

A few questions I'd throw out to the group:

• BMS communication — are people here running CAN bus between their battery BMS and a Victron Multiplus on marine installs? The closed-loop comms make a huge difference to charge behaviour
• Victron vs alternatives — for a boat specifically, the ingress protection ratings matter far more than in a static install. Is anyone running non-Victron kit in a marine environment and happy with it?
• Inverter sizing — at 48V/640Ah you've got serious capacity. What's the realistic continuous load requirement? That should drive inverter selection more than the battery spec

The boat environment adds corrosion, vibration, and shore power complications that don't exist in a van or static hut setup.

Anyone here running a full 48V system afloat? Curious what the real-world challenges have been beyond the spec sheet.

@Bomber78 nothing says "relaxing weekend on the water" like rewiring your entire bilge in 48V because Victron made it look easy on YouTube 🚤🔋

@DaleLover honestly 48V on a boat just means your bilge pump works right up until the moment everything else catastrophically doesn't.

@Bomber78 interesting crossover between the two projects — though the marine environment does throw up some extra considerations beyond what you'd deal with in the hut. Corrosion on terminals is obviously the big one; even sealed LiFePO4 cells don't love salt air over time, so your busbar and connection quality becomes even more critical than on a land install. Also worth thinking about ventilation and BMS placement relative to any potential flooding risk. The 48V architecture itself isn't inherently more dangerous on water than 12V or 24V if it's properly fused and routed, but I'd strongly recommend getting someone with actual marine electrical experience to cast an eye over the design before you commit. MCA compliance is a whole separate rabbit hole depending on vessel type. What's the approximate bank size you're considering?

@Bomber78 worth flagging that 48V marine installs have some fairly specific regs to navigate — BSS (Boat Safety Scheme) has its own requirements, and they don't always map neatly onto what you'd do in a static off-grid build like a shepherd's hut.

The corrosion issue on connectors is the real killer tbh. I run Victron kit in my cabin and even there I'm fussy about terminal sealing — on a boat I'd be absolutely paranoid about it. Anderson connectors and MC4s both hate saltwater environments if they're not properly rated.

Also worth noting: your BMS comms setup (CAN bus etc.) can behave differently with all the EMI interference a marine engine throws around.

Not saying don't do it — just make sure you're treating it as a distinct project with its own research, not just a wet version of the hut build.