Anyone else running a separate small solar setup just for their garden office?

My main home system handles the house and boat batteries, but I ended up putting a dedicated 200W panel and a Victron SmartSolar 75/15 on the garden office rather than trying to tie it all together. Running a 100Ah Fogstar Drift LiFePO4 in there, which keeps the lights, laptop, a small fan heater on low, and the router ticking over nicely most of the year.

The reason I kept it separate was cable run — the office is about 30 metres from the house and the voltage drop calculation made me wince. Easier to treat it as its own little island system. Only real headache is winter, where 200W just isn't enough on a grey January week and I have to top it up via a mains hook-up charger.

Wondering whether anyone else has done the same split approach, or whether you've gone full hybrid and tied everything together? Also curious if anyone's found a tidy way to automate the mains top-up so it kicks in at a set SOC threshold without having to remember to plug in manually.

Ian1968 | 847 posts

@NeilJackson Snap! I did exactly the same about two years ago. Mine's a 300W panel into a Victron 100/20 feeding a 100Ah lithium, and honestly it was the right call. Keeping it separate means any faffing about with the garden office system doesn't touch the main house setup, which the wife appreciates enormously! 😄

The only thing I'd add is make sure your cable run from panel to controller is properly sized - I initially went a bit tight on that and got more voltage drop than I'd have liked. Sorted it properly second time round.

Do you find the 75/15 copes alright if you're running a monitor and laptop simultaneously? I occasionally wonder if my 100/20 is slight overkill for what's essentially just a desk and a kettle.

BoatClive | 1,243 posts

Similar setup here, though I came at it from the opposite direction - started with the garden office and the main house system came later! One thing worth mentioning that neither of you have touched on: having it completely separate means if something goes wrong with either system, you're not taking everything down at once. I've had a BMS throw a wobble before and being able to isolate each setup independently was genuinely useful. Also means you can monitor and tweak them separately in the Victron Connect app without the numbers getting muddled together. What batteries are you both running in the office units? I've got a fairly modest 100Ah LiFePO4 in mine which honestly has been more than enough for lighting, laptop and a small fan heater on economy setting.

Russ1960 | 312 posts

Interesting thread this. I went a slightly different route - rather than a dedicated panel I ran a 63A armoured cable out to my office and feed it from a small battery bank that's charged via a secondary output on my main MPPT. Keeps everything under one roof monitoring-wise through VRM, which I prefer. That said, I can see the appeal of keeping it completely separate, especially if there's any fault finding to do down the line. @BoatClive curious what you started with in the garden office - was it just lighting and a laptop or something more demanding? My office ended up needing a proper inverter when I started running a second monitor and a small fan heater occasionally, which changed the whole sizing calculation pretty quickly.

Chopper84 | 524 posts

Nice to see others doing this! I've got a 400W panel on my workshop/office and kept it completely separate from the house system by choice - if one goes down it doesn't affect the other. The independence is worth more to me than any efficiency gains from combining them.

One thing worth mentioning that nobody's touched on - I added a small UPS between the inverter output and my office equipment. Means if there's a brief cloud-related voltage wobble the laptop and monitors don't even notice. Cheap insurance for the electronics.

@BoatClive curious what direction you came from - did you start with a smaller panel and upgrade, or go reasonably sized from the off? I slightly wish I'd gone 600W from the start given how much time I end up spending out there.