Microgrid - Insellösung im Anlagen - Verbund

Been reading about some interesting multi-site microgrid setups on the continent — Germans doing some seriously impressive compound installations, running admin buildings, EV wallboxes, and residential blocks all from a joined-up off-grid network. Got me thinking about where we're at over here with similar ambitions.

My own setup at the cabin is modest by comparison — a couple of Victron Multiplus-II units in parallel feeding into a Fogstar Drift 48V bank, with a Renogy MPPT array on the roof. Works brilliantly for the cabin itself, and I've got a Type 2 socket hanging off a dedicated inverter leg for slow EV charging. It's almost elegant.

But here's the thing I keep wrestling with: scaling. The German approach of clustering multiple microgrids into a kind of federated system — each node semi-autonomous but able to share capacity — feels like the logical next step for anyone with more than one building on site. I've got a small outbuilding I want to bring into the fold eventually, and I'm already dreading the complication.

A few questions for the collective:

• Has anyone here actually run two separate Victron installations on the same property with coordinated ESS profiles?
• What are the practical grid-code implications in the UK when you start chaining these things together, even in a fully off-grid context?
• Anyone feeding multiple wallboxes from battery storage without going insane managing load priority?

Feels like the industry is almost there on the software side — VRM is getting better — but the real-world implementation still requires a lot of manual thinking.

Would love to hear if anyone's pushed beyond a single-node system.

Interesting stuff, though I'd pump the brakes slightly on the "impressive" framing. The Germans are meticulous engineers, no question, but a lot of these Insellösung compound setups rely on grid-assist fallback that they don't always shout about in the write-ups. Not truly off-grid in the purest sense.

On my boat I run a modest Victron MultiPlus-II with Fogstar Drift lithium — nowhere near compound scale obviously — but the principles don't change: your weakest link is always load management, not generation or storage.

What I'd want to know about any of these German installations is:

• What's the actual DoD they're running day-to-day?
• How are they handling winter solar (spoiler: badly, same as us)
• Is the EV charging genuinely dynamic or just scheduled off-peak?

@FormerCop77 got any links to the original source material?

@FormerCop77 this resonates with me — I've been slowly expanding my own little "compound" over the years, starting with a garden office on Victron kit, then pulling in the static caravan, and now eyeing up a proper interconnected setup between the three structures.

What strikes me about these German Insellösung installations is the sheer confidence in going fully isolated from the grid. Over here we're still tiptoeing around DNO permissions and G98/G99 headaches even for modest setups.

My garden office alone took more paperwork than I'd care to admit.

The multi-site balancing piece is where it gets genuinely interesting though — having a central brain (Victron Cerbo in my case) arbitrating between loads across buildings. Scale that up to EV wallboxes and residential loads and you're talking proper systems engineering.

@DODGuy fair point on the meticulous framing — but honestly, a bit of that rigour wouldn't go amiss over here.

@Glen1983 that expansion story sounds familiar — my boat project started the same way, one Victron MPPT here, a battery bank there, and suddenly you're sketching out something that looks suspiciously like a proper microgrid on a napkin.

What genuinely excites me about these compound setups is the EV charging piece. Running a wallbox off a self-contained solar-plus-storage system rather than dragging in grid supply is something I've been quietly obsessing over. The Germans cracking that at scale — shared DC bus, intelligent load management across buildings — that's the roadmap right there.

The challenge I keep running into even on a modest single-site level is coordinating charge cycles so the EVs aren't hammering the batteries when solar's low. Curious whether anyone's seen Victron's ESS configurations stretched to cover genuinely multi-building scenarios, or whether you're inevitably looking at third-party SCADA layers at that point.

@Glen1983 @FrankGibson — that creeping expansion is exactly how the shepherd's hut ended up becoming a proper little microgrid here. Started with a single 200W Renogy panel and a modest Fogstar lithium, thinking that'd be it. Three years later there's a Victron MultiPlus holding everything together, a second hut on the same bus, and I'm eyeing up a wallbox for the van.

What I find fascinating about the German Insellösung approach is the deliberate planning from day one — they're designing for compound-scale from the outset rather than bolting things together retrospectively like the rest of us. My system works, but the cable runs tell the story of every impulse purchase I've ever made.

Anyone here actually designed a multi-site setup properly before laying a single cable? Genuinely curious whether that unicorn exists on this forum.