Sailing yacht off-grid — what works at sea?

Been following this thread with interest, though my experience is more static caravan than sailing. That said, spent enough time around boats to know salt water and electronics don't play nicely together.

The corrosion issue is real — worse than anything you'll deal with on land. If you're going Victron (which I'd recommend for reliability), their gear handles marine environments reasonably well, but you'll need proper ventilation and regular maintenance schedules. Don't skimp on the enclosure.

Solar's brilliant for boats. Flexible panels from Renogy mount flush and take up less space than rigid units, which matters when you're working with limited deck area. Angle of incidence is tricky though — you're constantly moving, so fixed installation won't give you optimal output year-round. Some folks use tracking mounts but that's another thing to maintain in a harsh environment.

Battery choice matters more on a boat than anywhere else. Lithium's lighter (important for stability), but if your budget won't stretch, a quality LiFePO₄ setup with proper BMS is miles better than old-school lead-acid. The weight saving alone improves sailing characteristics.

What I'm genuinely curious about: how are you managing freshwater systems alongside power? That's often the overlooked part. Wind generators seem popular for cruisers — reckon you're considering one?

Also, what size vessel and how long are you planning to be offshore? Range matters hugely for system sizing.

Salt spray is brutal, mate. I've seen Victron gear survive it reasonably well when properly mounted in sealed enclosures, but you're fighting a losing battle without serious corrosion management.

The real question is whether you're looking at solar, wind, or hybrid? Wind seems more logical at sea for consistent generation, but the salt deposits on panels become a nightmare. Renogy stuff tends to hold up decently if you're rinsing regularly, though that's labour-intensive.

What's your power draw like? And are you moored or actively sailing? Makes a difference between what's practical. Static caravans are almost easier in comparison — at least your batteries aren't getting dunked.

Salt corrosion is the real killer, not just the spray itself. Victron's definitely robust, but you need proper IP65+ enclosures and regular inspection of connections—even sealed gear can have micro-gaps where salt creeps in.

What I've seen work well on boats: isolate your battery bank aft, keep the inverter/charger in a dedicated, well-ventilated box with silica gel or active dehumidifiers. Stainless fasteners everywhere, and copper-based grease on terminals (not ordinary lithium).

Solar works brilliantly at sea if you mount panels on gimballed frames—keeps them optimally angled and gets better airflow underneath for cooling. Worth the extra weight.

The real difference from van/static setups is you're dealing with constant movement and moisture saturation. Budget extra for replacement connectors and monitoring. What's your power requirement looking like?

@FormerMechanic spot on about the salt water issue – it's probably the toughest variable on a yacht compared to land-based off-grid setups.

Building on what @LazyWatson and @RayWatson81 have said, I'd add that regular maintenance becomes absolutely critical at sea. Even with sealed enclosures, you'll want to inspect connections quarterly and consider sacrificial anodes on any metal components near your electrical system. Some folks swear by silicone conformal coating on circuit boards in high-moisture areas – worth looking into.

One thing I haven't seen mentioned yet: consider running redundancy into your system design. If one charge controller fails due to salt damage, you've got a backup. Same with batteries if budget allows. You're essentially applying caravan off-grid principles, but with harsher conditions and nowhere to easily pop ashore for replacement parts.

What size yacht are we talking about?

Salt spray's a nightmare, but the real trick is conformal coating everything that can't hide in an enclosure – Victron gear'll survive the abuse if you baby it, though at sea prices that's a lot of babying.

What actually gets me is the weight penalty of all that protective kit versus what you're trying to power. Saw a mate's narrowboat setup (admittedly freshwater, so easier) and even with Victron's compact offerings, he was stuffed for space. On a yacht where every kilo counts, you're potentially looking at a trade-off between battery capacity and corrosion protection that'll make your wallet weep.

@LazyWarden's right about sealed enclosures being your mate – stainless steel fasteners throughout and regular inspections matter more than the brand sometimes. That said, if you're committed to this, Victron's the least terrible option for standing a chance against the elements.

Good points raised here, lads. I'd add that beyond the hardware side, your power management strategy needs tweaking for marine use compared to land-based setups.

Battery monitoring becomes critical at sea – you can't just pop outside to check your charge controller like you would on a static install. A decent BMV or Lynx shunt will save you from nasty surprises when you're halfway to the Scillies. Victron's CCGX or Color Control lets you keep tabs remotely, which is proper handy.

Also worth considering: smaller capacity with quality beats larger banks that you can't properly maintain. Regular freshwater rinsing of exposed kit (especially around vents) makes a genuine difference to lifespan. @RayWatson81's right about IP65+ enclosures – I'd go higher if you can manage it.

One last thing – think about redundancy more seriously than you would ashore. Your charge controller going belly-up on a static system is annoying; at sea it's a real problem. Decent quality ancillary systems are worth the extra cost.

Cheers,
Lefty

Salt water's basically just aggressive networking, innit. Everything wants to introduce itself to everything else via corrosion.

@CornishNomad's right about conformal coating — though I'd argue the real MVP is just keeping stuff dry. Easier said than done on a boat, mind you. My mate's got a Fogstar setup on his narrowboat and

Spot on about the corrosion @CornishSkipper, but I'd focus on enclosure design first — conformal coating's a patch if your boxes aren't sealed properly in the first place.

Marine-grade stainless and proper gaskets matter more than you'd think. Seen too many setups fail because someone skimped on decent cable glands and didn't account for humidity cycling.

Battery-wise, lithium's tempting for weight but really needs solid BMS and thermal management at sea. The constant motion and temperature swings will stress cheaper packs. Lead-acid's boring but forgiving if you're vigilant with water levels.

My take: assume everything will corrode and design around it. Victron kit's bombproof in this regard — their connectors are industrial-spec for a reason. Also, keep your main switchboard and battery bank as isolated as possible from spray zones. Waterproof doesn't exist; controlled degradation is the realistic goal.

What's your battery strategy looking like? That'll drive a lot of the enclosure decisions.

Right, salt spray's a proper nightmare. Had a mate's narrowboat setup get absolutely trashed by river conditions, and that's freshwater — can't imagine what the sea does.

Thing is, enclosure alone won't cut it if you're looking at long-term reliability. You need active ventilation to manage condensation inside the boxes, else you're just creating a damp chamber that'll corrode from the inside out. Fogstar make decent marine-grade enclosures with this built in.

Battery-wise, LiFePO₄ in a sealed, temperature-controlled box is probably your safest bet — no off-gassing concerns, and you dodge half the corrosion issues with lead acid. Victron kit's pricey but their marine-rated gear genuinely handles the environment better than consumer-grade alternatives.

Also worth considering: cable runs. Everything wants tinned copper and proper IP67 connectors, not the usual automotive stuff. Cost adds up quick, but one catastrophic short at sea isn't worth the saving.

What's your gen setup looking like — solar only or planning a backup?

The corrosion thing's worse on a boat than in a static setup, yeah. Wind speed + salt = everything gets attacked. On my narrowboat I'm dealing with freshwater mostly, but even that's rough on exposed connectors.

Key difference I've noticed: you lot are moving through the environment, so it finds you. Conformal coating helps but @MarineGaz is right — enclosure design matters more. I'd say invest in proper IP67+ boxes for batteries and controllers rather than trying to save a quid upfront. Victron gear's pricey but their enclosures actually keep moisture out.

One thing that helped mine: regular checks on terminal connections. Corrosion creeps in quietly. Even freshwater gets in there if you're not careful.

Salt water's another beast entirely though — if you're sailing regularly, you might want stainless fasteners throughout and consider whether lithium's worth it over sealed lead-acid for your setup. Simpler = fewer things to corrode, especially if you're not confident doing regular maintenance at sea.

Lived on a boat for three years, now in a cabin setup. The corrosion angle is real but honestly the bigger issue is movement. Everything vibrates, shifts, corrodes faster because of it.

Victron gear survives better than most — their enclosures are properly sealed. But even then, you're looking at replacing cabling and connectors every 18-24 months if you're serious about it. Salt spray gets everywhere.

What actually made the difference for me:

• Kept the battery bank and charge controller in a dedicated cabin box, away from direct spray
• Stainless steel terminals, full stop. Not "marine grade" — actual stainless
• Conformal coating helps but @MarineGaz is right, it's not a fix. Better to design it out first

The static caravan lot have it easier. Even in harsh coastal locations, you're not getting the constant movement working against you. On a boat, your best bet is redundancy. Second inverter, spare controller, extra cabling. Expect maintenance as part of your routine.

Wind turbine's pointless at sea unless you're moored permanently —

Had a mate with a Westfalia who'd spend summers moored up. His Victron gear lasted fine, but the real killer was vibration—everything loose eventually worked itself free. On a boat you're fighting movement and salt. Static caravan's a doddle by comparison. Motion plus corrosion is a different beast entirely from what we deal with on land.

@ExChippie94's right — vibration's a proper nightmare. Had a mate's caravan whose battery terminals worked loose just from being towed; can't imagine what a boat's constant pitching and rolling does to connections. Even quality kit like Victron struggles if everything's rattling about. Gotta be obsessive with the torque wrench on a boat,