Anyone else using a small wind turbine alongside solar on their off-grid cabin build?

I've just finished roughing in the electrics on my 12x8 timber cabin up in the Scottish Borders and I'm starting to think my 400W of solar panels isn't going to cut it through the winter months. We get some proper grey spells up here where I might go 4 or 5 days seeing barely any sun at all. I've got a 200Ah lithium battery bank and a 40A MPPT controller, which works a treat from April to September, but October onwards it's a different story.

I've been looking at the Rutland 914i and the Ampair 100 as possible additions — both seem reasonably well regarded for small domestic/cabin use. My site does get decent wind, probably averaging 5-6 m/s based on the NOAA data I pulled for the area, so it seems like it could actually make sense rather than just being a gimmick. Wondering whether the output figures manufacturers quote are remotely realistic in practice, and whether a small turbine would genuinely take the edge off those dark winter weeks.

Has anyone actually wired one into a similar 12V or 24V system alongside solar? Particularly curious about how you handled the charge controller side of things — did you run a dedicated wind charge controller or find something that handles both inputs? And did you need planning permission for the turbine mast given it's a cabin rather than a main dwelling?

Reply by Spud17:

@Doug1981 — good timing on this question, Scottish Borders winters will absolutely humble a solar-only setup! I ran 400W solar alone on my Welsh hillside place for one winter and it was genuinely miserable by December.

I added a 400W turbine (a Rutland 914i) the following spring and the difference was noticeable — wind tends to pick up exactly when the sun disappears, so they complement each other really nicely in practice.

Few things worth knowing though: check your local planning situation first, especially if you're near any designated landscape areas. Also the noise can surprise you — not terrible, but you notice it at night.

What's your battery bank looking like? That's often the bigger bottleneck than generation capacity for getting through prolonged gloomy spells. Knowing your storage setup would help give more specific advice.

My Victron MPPT wept actual tears last January — wind turbine didn't even flinch. 🌬️

Reply by TracyRobinson:

@Doug1981 — we're in a similar setup, rural Northumberland, so fairly comparable conditions to you. We added a 500W Rutland turbine to our 600W solar array two winters ago and honestly it's transformed our winter resilience. The key thing nobody told us beforehand is tower height matters enormously — our first install was too low and we got turbulent airflow off the treeline. Got it up to 6 metres and the difference was night and day. Worth checking your prevailing wind direction carefully before committing to a position. Also factor in the noise if you're sleeping in the cabin — not unbearable, but definitely noticeable on gusty nights. @VE_Electric is right that wind genuinely earns its keep when the sun's nowhere to be seen. What battery capacity are you running currently?

Reply by Tommo10:

@Doug1981 worth looking at the Eclectic Energy D400 if you haven't already — it's a UK-made unit and well suited to the kind of gusty, lower-average-wind conditions you get in the Borders rather than needing constant strong winds to be worthwhile. I've got one paired with 600W solar on my setup and the two genuinely complement each other brilliantly — windy days tend to be overcast days, so they fill each other's gaps nicely.

One thing I'd flag though: check your local planning situation before you commit. Permitted development rules for wind turbines can be a bit of a minefield depending on your land classification. Might be worth a quick call to the council. 🏴󠁧󠁢󠁳󠁣󠁴󠁿

Slapped a small turbine next to my panels last autumn and honestly the thing earns its keep on every miserable grey day that would've left my Fogstar batteries looking sorry for themselves — Scottish Borders is basically a wind turbine's dream posting, @Doug1981, you're practically obligated at this point. 🌬️☀️

Really worth thinking carefully about your charge controller setup before committing to a turbine, @Doug1981. Wind and solar need separate MPPT controllers — or a purpose-built combined unit — because the input characteristics are fundamentally different. Dumping excess wind energy safely requires a proper dump load (a resistive water heater element works well) otherwise you'll damage the turbine when batteries are full and there's no load to absorb the output.

For your Scottish Borders location, also check the turbine's cut-in wind speed spec carefully. Many cheaper units need 3-4m/s just to start generating meaningfully. The Victron MPPT range handles solar beautifully but you'll need separate wind charge regulation alongside it.

My motorhome setup uses Victron kit throughout and the monitoring via VictronConnect makes diagnosing input conflicts straightforward — well worth considering a similar approach for the cabin so you can see exactly what's contributing what.