Planning Solar/Battery System for house and barn in Central Ohio

Interesting project — though I'll flag that most of us here are UK-based so some of the specifics (grid tie regulations, net metering etc.) will differ from what you're dealing with in Ohio. That said, the fundamentals are the same wherever you are.

For a house and barn setup, the big decision upfront is whether you're running one centralised battery bank or separate systems for each building. I went centralised on my boat and it's simplified monitoring no end, but running cable between two structures adds its own headaches — voltage drop, weatherproofing, the lot.

On the battery side, LiFePO4 is the obvious choice at this scale. Fogstar and Pylontech are popular here in the UK — not sure what's readily available stateside but I'd imagine Battle Born and similar are your go-to. The chemistry is what matters more than the brand anyway.

Victron kit is genuinely worth the premium if you're doing something this size. Their MultiPlus inverter-chargers and Cerbo GX monitoring work brilliantly together, and their support network is solid internationally.

A few questions that'd help the conversation:

• What's your approximate daily consumption for both buildings?
• Are you planning grid-tied with battery backup, or full off-grid?
• Does the barn have significant loads (machinery, lighting, EV charging)?

The barn usage in particular changes the sizing calculation massively. A workshop with power tools is a completely different beast to just lighting and a few sockets.

Would love to see what others think — especially anyone who's done a dual-building setup. Is there anyone here with experience bridging two structures efficiently?

Worth adding to what @BoatMel said — the battery chemistry side of things is pretty universal regardless of which side of the Atlantic you're on, so we can definitely help there.

I've been running a Victron/Fogstar LiFePO4 setup in my motorhome for a couple of years now, and the principles around BMS configuration, state of charge management, and charge/discharge curves translate completely to a house or barn installation.

Where you might hit a wall with us is anything utility interconnection specific — your Ohio grid regulations will be entirely different to our DNO processes here in the UK.

Post up your planned system specs — panel wattage, battery capacity you're targeting, whether the barn needs to be independent from the house — and we can get into the details that do apply universally.

Agreed with @Stacey on chemistry being universal — LiFePO4 is LiFePO4 whether you're in Ohio or Orkney.

One thing worth flagging specifically for a house and barn setup: you'll want to think carefully about whether you're running one central battery bank with long cable runs, or separate banks at each location. Long DC runs are brutal for losses — I learned this the hard way on a marina project where the cable costs alone would've bought a second Victron Multiplus.

For barn separation, a second smaller bank locally situated often makes more sense than fighting voltage drop. Victron's ESS system handles multi-location setups elegantly if you go that route, though the US equivalents will serve you equally well.

What are your rough loads for each building separately? That'll drive the architecture more than anything else.

Welcome to the forum @BoatMel — good to have you here, even if you're posting across the pond!

Picking up on what @MarinePhil and @Stacey have covered on chemistry — one thing worth drilling into for your barn setup specifically is BMS communication. Are you planning to have both the house and barn batteries talking to a single inverter/charger, or separate systems? That topology question affects everything downstream.

I'm running a Victron MultiPlus on my shepherd's hut and the BMS integration decisions I made early on caused me no end of headaches later. Worth getting that architecture nailed before you buy anything.

What battery capacity are you currently considering, and do you have a rough load estimate for the barn separately from the house? Those two figures will shape most of the conversation.

LiFePO4 chemistry chat aside, don't sleep on the BMS communication protocol differences — my Fogstar Drift cells talk nicely to my Victron kit via CAN bus, but what plays well together in the UK might not match whatever inverter brands are dominant in the Ohio market.

Picking up on @Brummie84's point about BMS comms — worth flagging that voltage thresholds can catch people out too. American kit often assumes 120V AC infrastructure, which flows downstream into how some inverter-chargers are configured at the factory. When I set up my narrowboat system with Victron, I had to dig into VEConfigure to adjust absorption and float voltages that had clearly been templated from a North American build.

For Ohio specifically, your grid-tie regulations will be governed by PUCT equivalents at state level rather than DNO rules here — completely different landscape to UK G98/G99 notification requirements.

The battery chemistry being universal is true, but the ecosystem around it absolutely isn't. Worth double-checking that any Fogstar or similar cells you're eyeing will ship internationally before getting too attached to specific product recommendations from this side of the pond.