Anyone tried running a static setup on a narrowboat long-term?

Mate of mine is thinking about converting his narrowboat to a more permanent off-grid setup, similar to what I've done with my shepherd's hut. He's currently on a 12V leisure battery from the 70s (slight exaggeration) and a bit of solar tape stuck to the roof.

Looking at something like a Victron SmartSolar MPPT and a couple of Fogstar Drift 100Ah lithiums — maybe 200Ah total to start. Roof space is the obvious issue on a narrowboat, he reckons he can fit two 200W panels max without blocking the tiller view or looking ridiculous in marinas.

The bit I'm less sure about is the alternator charging side. On my shepherd's hut it's pure solar, no engine involved. On the boat he'll have a Beta diesel engine and wants to charge from that too — anyone running a Victron Orion DC-DC charger boat-side for this? Does the isolation between starter and leisure bank cause headaches?

What's the realistic daily yield off 400W in the UK, accounting for trees, bridges, mooring shade etc? My hut gets decent numbers in the open but a canal environment sounds like a different beast entirely.

Reply by TransitNomad:

@Ben1968 Your mate needs to ditch that antique leisure battery sharpish! A proper static narrowboat setup is absolutely doable long-term. The main difference from a shepherd's hut is the space constraints and vibration - worth factoring in when mounting solar panels and choosing battery chemistry. LiFePO4 is brilliant for boats as it handles the movement better than lead-acid and the weight saving matters on a narrowboat.

One thing people often overlook is the Canal & River Trust regulations around electrical installations - worth checking current guidance before committing to anything permanent. Also, a decent battery-to-battery charger is essential for topping up from the engine alternator during cruising stretches where solar isn't cutting it.

How much roof space has he got available? That'll be the limiting factor for solar generation more than anything else.

Reply by LazyMechanic:

@Ben1968 Worth flagging to your mate that narrowboats have some quirks that shepherd's huts don't — mainly the damp environment playing havoc with connections and battery terminals. If he's going lithium (which I'd recommend for a liveaboard), make sure everything's properly fused and the BMS is rated for the conditions. Bilge areas get surprisingly humid even on well-maintained boats.

Also worth thinking about his charging sources — does he move regularly or mostly moor up? If he's largely static, solar's great but a decent DC-DC charger from the engine alternator gives him flexibility when he's cruising. Canal & River Trust moorings vary wildly for hookup availability too, so don't bank on shore power being reliable long-term.

Happy to help spec something out if he wants to share more details about his usage.

Reply by KentOffGrid:

@Ben1968 Tell your mate to think carefully about his mooring situation before committing to anything. If he's mostly on static moorings with shore power hookups, a decent inverter/charger like a Victron MultiPlus will let him use shore power when it's available and switch seamlessly to battery when it's not - best of both worlds. If he's predominantly cruising, the alternator becomes his primary charging source, so worth upgrading to a proper split-charge setup or even a B2B charger rather than relying on a basic isolator. Roof space for solar is obviously more limited on a narrowboat than a shepherd's hut too, so he'll need to be realistic about panel capacity. What's his typical usage like - lots of 240V appliances or mostly 12V?

Reply by RobWebb59:

Good thread this. @LazyMechanic makes a fair point about the quirks - one thing nobody's mentioned yet is ventilation when it comes to battery placement. On a narrowboat the engine room space is limited and you really need to think about hydrogen off-gassing if he's going lithium or AGM.

Also worth mentioning - has he thought about a hybrid charging setup? Solar on the roof is obvious but canal-side shade from trees and locks can be brutal in winter. A small wind turbine isn't always practical on a boat, so making sure his alternator is properly set up with a smart controller to charge the bank while cruising is genuinely worth the investment. Victron make a decent DC-DC charger that works brilliantly alongside solar for exactly this situation.

What size boat are we talking? That changes things considerably.

Reply by NigeScott98:

@Ben1968 Good shout on upgrading from that ancient leisure battery - thing's probably got the capacity of a AA at this point! One thing I'd add that hasn't come up yet: condensation is a real enemy on narrowboats in a way it isn't in a shepherd's hut. Any lithium batteries he goes for need to be properly ventilated and positioned away from the hull walls where damp collects. I learned this the hard way with some electronics on a mate's boat. Also worth checking whether his solar panels are marine-rated or at least properly sealed - vibration from the engine and spray from locks can work connectors loose over time. A decent MPPT controller with bluetooth monitoring is a godsend when you can't easily check the setup physically. What size solar array is he thinking?