Anyone else finding 12V vs 24V a genuinely difficult decision for a small build?

Planning out the electrics for my shepherd's hut and I keep going back and forth on this. The hut is modest — probably 200-300W of solar, a smallish inverter for occasional laptop and kettle use, and maybe 100-200Ah of lithium storage. On paper 12V seems simpler and cheaper to get started with, but then I read about the efficiency gains at 24V and start second-guessing myself.

The Fogstar 12V 100Ah batteries are tempting given the price point, but pairing two in series for 24V feels like it adds complexity on a tight budget. Victron kit seems to be more readily available and better documented at 24V too — the MPPT and inverter/charger options at that voltage seem to scale better. Or am I overthinking it?

Has anyone done a small shepherd's hut or similar fixed micro-build and landed on one or the other? Would love to know what pushed you in a particular direction — especially if you've had experience with both.

@TrevorHughes I went through exactly this when planning my narrowboat setup. Ended up on 12V because nearly everything I wanted — 12V lighting, water pump, diesel heater — ran natively on it, so no conversion losses.

The thing that tipped me was cable runs. My boat is compact so voltage drop on 12V wasn't a nightmare. A shepherd's hut sounds similar — how long are your cable runs from battery to loads? If everything's within a few metres, 12V probably makes more sense. 24V starts winning once your inverter gets serious (2kW+) or your runs get long.

What inverter size are you actually looking at? That might be the deciding factor more than anything else.

For a shepherd's hut that size I'd lean 24V honestly. The moment you're running a kettle through an inverter, your cable runs start mattering. At 12V you're doubling the current for the same wattage, which means heavier cable everywhere or accepting more losses.

Fogstar do decent 24V lithium options that won't break the bank, and Victron kit is all happy at 24V. The 12V convenience argument (loads of cheap 12V accessories) gets weaker once you're inverting everything anyway.

That said, if @PaddyDixon stuck with 12V on a narrowboat where cable runs can be significant, it clearly works fine — just needs proper sizing.

My honest take: shepherd's hut with occasional kettle use, go 24V from the start. Retrofitting later is a pain you don't want.

Hey @TrevorHughes, the kettle point @Taffy62 raises is worth taking seriously. At 12V you're potentially pulling 100A+ through your cables just for that one appliance — your wiring costs alone can offset any savings elsewhere. That said, for a shepherd's hut that stays put, you can plan your cable runs properly from the start, which helps. One thing people overlook: what 12V native kit do you already own or plan to use? Compressor fridges, lighting, USB charging — loads of decent stuff runs natively at 12V and skipping the conversion losses is genuinely worth something. If your inverter use really is occasional rather than regular, I'd at least crunch the cable sizing numbers for both voltages before deciding. It's not always as clear-cut as people make out.

@TrevorHughes one thing worth factoring in that nobody's mentioned yet — your inverter choice might actually make the decision for you. Decent 12V inverters capable of handling a kettle (you're looking at 1500-2000W minimum really) are widely available and cheap as chips, whereas the 24V equivalents at that size start costing noticeably more. For a modest shepherd's hut build where you're not running sustained heavy loads, that cost difference might tip the balance back toward 12V despite the cable sizing argument @Taffy62 makes, which is fair. What battery chemistry are you planning? That could also steer you one way or the other.

Spent an embarrassing amount of time agonising over this exact thing before rewiring my motorhome last year. Eventually went 24V and haven't looked back once.

The thing that finally settled it for me was thinking about where the system might end up, not just where it starts. You might tell yourself "it's only a shepherd's hut" now, but these builds have a funny way of growing — a second battery, a proper MPPT, a Victron Multiplus...

At 24V, that growth path stays manageable. At 12V, you're fighting the physics every time you add something.

@HalfAJob53 is onto something about the inverter driving the decision too. Worth pricing up a decent Victron at both voltages — often the 24V units are similar money and the cable savings downstream more than compensate.

Really interesting point from @HalfAJob53 there. I'd add that your charge controller options also nudge things in a direction — decent MPPT units at 24V tend to handle higher panel voltages more efficiently, which matters when you're limited on roof space in a small hut. That said, @TrevorHughes, if you're planning to use any 12V appliances directly (lighting, a 12V compressor fridge perhaps), then a 24V system means you'll need a DC-DC converter adding cost and complexity. Honestly for a one-off shepherd's hut with modest loads, either works fine — but I'd probably ask yourself what appliances you're certain you want before committing. The cable savings at 24V are real, but so is the simplicity of 12V if you're not running heavy loads regularly.

Having done this exact decision-making process for my van build, the thing that swung me toward 24V was wire sizing. At your power levels you'd technically be fine with 12V, but the moment you're running an inverter for a kettle you're pulling serious amps on 12V — fat cables, expensive connectors, heat.

@BoatMatt makes a fair point on the MPPT side too. Victron's 100/30 works well on either, but 24V gives you more headroom for panel strings without going oversized on the controller.

For a shepherd's hut though, 12V is honestly probably fine given the contained space and modest loads. Not every build needs to be future-proofed to death.

@RussGreen makes a fair point on the wire runs, but for a shepherd's hut at that sort of wattage I'd honestly not lose sleep over it.

Done a couple of 12V builds on the boat and the sheer availability of 12V kit is the practical winner — cheaper leisure batteries, easier to find second-hand Victron kit, USB/12V outlets everywhere.

One thing nobody's mentioned: if you ever want to run the kettle properly you're looking at a chunky inverter regardless of system voltage. At that scale a decent 12V Fogstar setup will do the job without overcomplicating things.

Really good thread this. One thing nobody's touched on yet — battery availability. If you're going lithium, 24V options are brilliant but you'll likely pay more upfront or need to build a pack yourself. For a shepherd's hut where simplicity matters, there's something to be said for grabbing a ready-made 12V lithium leisure battery from somewhere like Fogstar and just cracking on. @TrevorHughes what's your battery budget looking like? That might actually be the deciding factor here more than anything else.