Anyone else using a small inverter generator as emergency backup alongside their solar setup?

Just picked up a Honda EU22i after last winter left me with three days of barely any charge from my 400W panel array — a proper nightmare. I've been mostly solar-only up to now with a 200Ah lithium bank, but that grey January weather really exposed how fragile the setup is when you need it most. The generator cost me about £1,100 from a local dealer and I'm already feeling better about winter resilience.

I'm running it through a 30A DC-DC charger rather than connecting it to my Victron Multiplus directly, partly because I wanted to keep things simple and partly because I wasn't sure about the EU22i's output stability with an inverter/charger. It's getting roughly 18-20A into the battery which seems decent for a 2.2kVA machine, but I suspect I'm leaving some capacity on the table.

Has anyone integrated a petrol generator properly into a Victron system — ideally with the Multiplus doing the AC coupling and managing charge cycles automatically? Keen to know what settings people are using, whether the EU22i plays nicely with Victron kit, and roughly how many hours run time you're finding you need to top up a similar sized bank on a bad week. Any experience with storage and fuel stabiliser over summer when it's sitting unused would be handy too.

@BigAl31 similar situation pushed me toward looking at this too. Quick question — how are you actually connecting it to charge your batteries? Are you running it through a proper inverter/charger like a Victron Multiplus, or just plugging a standalone charger into the generator's AC output?

I've got a 200Ah Fogstar Drift and I'm wary of the voltage/frequency stability from these smaller generators causing issues with sensitive charge controllers. Honda's inverter generators are apparently cleaner than standard ones but I'd still want to know what people are actually running between the genny and the battery bank. Anyone using a Victron setup had issues with the generator's AC quality tripping anything out?

Good shout @BigAl31, the EU22i is a cracking bit of kit for exactly this scenario. I run a similar hybrid setup — 600W solar with a 300Ah lithium bank, and an older Honda EU20i as the cavalry when we get those grim grey weeks in January.

One thing worth mentioning that nobody seems to talk about much — get yourself a proper battery-to-battery charger rather than just plugging a basic charger into the inverter output. Much more efficient and your generator won't be running nearly as long to top things up. I use a Victron Orion, makes a noticeable difference.

Also worth checking @Mike1980 — if your question was about connection, most people wire through their existing charge controller setup or use a dedicated AC charger input if your inverter/charger unit supports it. What inverter are you running?

Great setup @BigAl31 — the EU22i is a solid choice. One thing worth considering if you haven't already: look into running the generator through your solar charge controller's AC input if your inverter-charger supports it, rather than direct to the battery. Keeps everything managed properly and avoids any charging profile issues with your lithium cells.

Also worth knowing — those Hondas are surprisingly frugal at partial load, so if you're just topping up a depleted bank you won't be burning through fuel as badly as you might expect. I tend to only kick mine on once the battery drops below 20% during a grim January stretch, runs maybe 2-3 hours and I'm sorted.

What inverter-charger are you running with that 200Ah bank? Makes a difference to how you'd best integrate it.

Good timing on that purchase @BigAl31 — I went down the same route about 18 months ago after a grim January wiped out my panels for nearly a week solid. One thing worth mentioning that nobody's touched on yet: keep an eye on your runtime versus actual charge input. I found I was running mine far longer than needed because I wasn't monitoring properly. Grabbed a decent battery monitor and now I just run the generator until I hit around 80% SOC and let the solar top it off. Massively cuts fuel costs and runtime hours on the engine. Also worth checking your inverter/charger is set up correctly to accept the EU22i's output — some cheaper units can be a bit fussy with inverter generator waveforms despite them being clean sine wave. Never had issues with mine but seen others struggle.