Anyone else running Victron on a narrowboat in winter — worth the premium?

Just swapped out my old PWM setup for a Victron SmartSolar MPPT 100/30 on the boat and honestly the difference in low-light harvesting is embarrassing — old controller basically took November through February off.

Running 200W of Renogy panels flat on the cabin roof (not ideal angles, I know) into a pair of Fogstar 100Ah lithium batteries, and even on a grim grey canal day I'm pulling 3–4A where before I'd get practically nothing.

The Victron app via Bluetooth is dangerously addictive — I've spent more time staring at charge graphs than actually going anywhere.

Question is: anyone found a decent way to tilt-mount panels on a narrowboat roof without them acting like sails and terrifying other boaters? Seen a few DIY hinged frames but nothing that looks like it survives a proper gust.

@VoltTom the low-light harvesting difference is exactly why I made the switch on my motorhome build. What most people miss is pairing the SmartSolar with a Victron BMV-712 battery monitor — once you've got accurate state-of-charge data feeding back, the MPPT's adaptive charge algorithm becomes genuinely useful rather than just theoretical.

Worth checking your absorption voltage is correctly set for your battery chemistry too. I run Fogstar Drift LiFePO4 cells and had to manually configure the charge profile rather than trust a preset — boats sitting idle over winter can end up with improperly maintained cells if the defaults aren't right.

One winter-specific tip: enable the temperature compensation if you're on AGM/lead. Voltage requirements shift significantly once canal temperatures drop below 5°C.

@VoltTom really interesting to read this — I'm not on a narrowboat but running Victron SmartSolar in a tiny house setup and the winter low-light performance genuinely surprised me too.

Quick question though: are you finding the Bluetooth monitoring via the VictronConnect app reliable enough day-to-day, or do you also run a Cerbo GX for proper logging? I've been debating whether the Cerbo is worth the extra outlay or whether the app alone is sufficient for keeping an eye on state of charge through the short December days.

Also curious — what battery bank are you paired with? I'm currently weighing up Fogstar Drift lithium vs staying with AGM for my own system, and I imagine the chemistry choice matters even more on a boat where temperatures can really swing overnight.

@VoltTom running a similar setup on my narrowboat and the winter performance genuinely surprised me. Quick question though — what panels are you running and how are you handling the shading issue? Narrowboats are notorious for trees, bridges, mooring situations where half the array gets covered at weird angles.

I'm wondering whether it's worth splitting into two separate MPPT inputs rather than stringing everything together and losing the whole array to partial shade. Has anyone actually done that comparison on a boat specifically?

Also curious what battery bank you're paired with — I've been eyeing the Fogstar Drift lithium cells but unsure if the Victron BMS integration is straightforward enough for a liveaboard situation where I can't always be fiddling with settings mid-winter.

@VoltTom same experience here — was skeptical about the price but the MPPT algorithm alone justifies it in winter. What really sold me was the Victron Connect app showing exactly what you're pulling in real time. Makes it easy to know when to plug in vs. run the engine.

Main thing I'd add for narrowboat use specifically: keep an eye on your battery temp compensation. Canal air gets damp and cold overnight and lithium behaves differently than the defaults assume. Sorted mine with a BMV-712 and the temp sensor — small extra cost, big difference.

@VoltTom worth adding that the SmartSolar's adaptive absorption is particularly valuable on a narrowboat in winter — when you're moving, your solar input is inconsistent and a dumb controller will keep resetting the charge cycle. The Victron handles interrupted charging far more intelligently.

I'd also strongly recommend pairing it with a BMV-712 battery monitor if you haven't already. On a boat you need accurate state-of-charge data, especially when running 240V inverter loads through an overnight mooring. The Bluetooth integration via VictronConnect means you can check everything from the cabin without going into the engine bay in January.

One practical note — make sure your MPPT is mounted somewhere with decent airflow. Mine throttled back noticeably last summer when I'd boxed it in too tightly. Less of a winter concern obviously, but worth planning ahead.