Anyone else built a garden office solar setup for under £500? Share your builds

Been running my garden office on solar for about eight months now and managed to keep the whole thing under £500 all-in. Went with a 200W Renogy panel (picked up on Amazon for around £120), a Victron SmartSolar 100/20 MPPT (£85 used on eBay), and a single 100Ah Fogstar Drift LiFePO4 (£189). Throw in some cable, a fuse block, and a cheapish 300W inverter and I just about squeezed under budget.

Typical load is a laptop, a couple of LED lights, and a small monitor — maybe 150-200Wh per day. Even through a grey November I was only occasionally dipping into the bottom 20% of the battery. Honestly surprised how well it's held up. The Victron app making it easy to keep an eye on state of charge has been a proper game-changer for peace of mind.

Curious what others have managed to put together on a tight budget. Did you go second-hand panels? AGM instead of lithium to save upfront cost? Anyone running something similar off just one panel or pushed to two? Would be good to see some real numbers rather than theoretical stuff.

@AlexPalmer60 similar boat (literally — done this on my narrowboat before scaling up for the garden). One thing worth adding: second-hand panels are seriously underrated for budget builds. Grabbed two 250W panels off eBay for £60 the pair — slight cosmetic damage, zero performance issues after testing.

Also worth considering Fogstar for the battery side if anyone's building fresh — their lithium cells punch well above their price point compared to some of the gel setups people cobble together.

The hidden cost nobody mentions is cable runs. If your office is more than about 10 metres from your panels, voltage drop will bite you. Factor in decent 6mm² cable early or you'll be buying it twice like I did.

Really nice build @AlexPalmer60! Eight months of solid runtime on that budget is genuinely impressive.

One thing I'd add that nobody's mentioned yet — worth thinking about cable runs between the panel and your controller. Lots of people underestimate voltage drop on longer runs and end up leaving free power on the table. If your office is more than about 5-6 metres from where your panel's mounted, bumping up your cable gauge (or going 24V if you're not already) makes a noticeable difference to real-world efficiency.

Also, for anyone doing this in a timber office — a small ventilated enclosure for your battery is well worth the effort, both for safety and because LiFePO4 cells in particular prefer not to cook in summer. Picked up a decent vented cabinet from a reclamation yard for about £15 which sorted that nicely.

Really solid build @AlexPalmer60, and eight months is a decent enough track record to trust the numbers.

One thing I'd throw in that nobody's mentioned yet — keep an eye on your panel angle as we head into winter. A 200W panel lying fairly flat might surprise you with how much output drops on low December sun angles. Even propping it up to 60-70 degrees from horizontal can make a meaningful difference to those short winter days when you're still trying to run a monitor and keep the heating going.

Took me a while to realise why my setup was underperforming in January before I started adjusting seasonally. Cheap fix, costs nothing, just needs a bit of fiddling with the mount. Worth it though.

Eight months without crying at an electricity bill is basically a spiritual achievement at this point.

My tiny house setup taught me one thing: the battery is where budgets go to die — spent more on my Fogstar Drift 100Ah than everything else combined and I'd do it again without blinking. If you're still running lead-acid under that desk @AlexPalmer60, that's where your next £150 needs to go before anything else, because lithium genuinely changes the maths on a small system like yours.

Also worth checking your Victron settings aren't being too conservative on the absorption voltage — factory defaults often leave 10-15% capacity sat there doing nothing, which on a 200W panel in a British winter is basically criminal.

@AlexPalmer60 decent enough build but I'd want to know what your winter performance actually looks like before calling it a success. 200W panel in a UK December with the sun barely clearing the roofline is a very different beast to August.

Running similar on the narrowboat — Victron SmartSolar 100/20 paired with a Fogstar Drift 100Ah LiFePO4. The low-irradiance performance is where most budget builds fall apart. I've seen days in January where I'm pulling maybe 18-22W peak from a nominal 200W panel.

What's your consumption profile look like? Monitor, laptop, lighting? Because if you're running anything with a meaningful draw through a grey January fortnight, that single panel may leave you scrabbling for the extension lead from the house — which rather defeats the point, doesn't it.