Anyone else running a cheap 100W panel + leisure battery setup and actually getting decent results?

Finally got round to putting together a basic solar setup for the camper and honestly can't believe how well it's working for the money. Picked up a 100W mono panel off eBay for £45, a 20A PWM controller from Amazon for £12 (Epever Tracer, nothing fancy), and I'm running it into an old 110Ah leisure battery I had sitting in the garage. Total outlay was about £60 new, basically nothing if you don't count the battery.

Day-to-day I'm powering a 12V compressor fridge (about 45W), phone and laptop charging, and a couple of LED strips. In decent summer weather I'm seeing 4-5A coming in through most of the afternoon which is more than enough to keep up. Obviously cloudy days are a different story but I'm not fully off-grid, just trying to reduce how often I'm running the engine to top things up.

My question is — is there much point upgrading to MPPT at this scale, or is the PWM doing a fair enough job? I've read conflicting things. Some people swear MPPT makes a noticeable difference even on a single 100W panel, others say it's not worth it until you're running 200W+. Keen to hear from anyone who's actually switched and measured the difference rather than just going on theory.

@Tom1981 curious what leisure battery you're running with that? I've got a similar budget setup in my Transit — 100W Renogy panel with a basic PWM controller — but I'm still on a knackered old lead acid and wondering if that's where I'm losing efficiency.

Been looking at a Fogstar Drift 100Ah lithium to swap in but can't quite justify the cost yet. Did you stick with lead acid or go lithium?

Also worth mentioning — tilt angle made a massive difference for me once I actually bothered to optimise it properly rather than just flat-mounting. Picked up maybe 20-25% more output on clear days. Obvious in hindsight but easy to overlook on a budget build when you're just trying to get something working.

Been running almost exactly this setup for about 18 months now in my old Sprinter. @Tom1981 you're right, the results are surprisingly decent for the outlay. One thing I'd add — don't overlook the quality of your cabling and connections. I wasted a good few weeks wondering why my charge figures looked low before realising I had a dodgy crimped connection losing me voltage before it even reached the controller. Sorted that and saw an immediate improvement.

@LDVNomad a decent AGM will serve you better than a standard wet leisure battery if you can stretch the budget slightly — handles partial state of charge much better in real-world camper use. I picked up a 110Ah AGM for around £85 on a bank holiday sale and it's been solid.

Really glad this thread came up — I've got a 100W mono on the roof of my T5 paired with an old 110Ah leisure battery I picked up from a local garage for £40. Honestly the combo has been solid for weekends away.

One thing worth mentioning that I don't see discussed enough — panel placement makes an enormous difference with these smaller setups. Even partial shading from a roof bar or aerial can absolutely kill your output with PWM controllers. I spent weeks thinking my panel was underperforming before I realised one corner was catching shade mid-afternoon.

@LDVNomad interested to hear what battery you're running too — in my experience the battery condition matters far more than the panel wattage at this scale. A tired battery will let the whole setup down regardless of how much sun you're getting.

Really useful thread this. One thing I'd add that hasn't been mentioned yet — keep an eye on your connections, especially if the panel's been on the roof through a British winter. I lost a fair chunk of efficiency last year and turned out one of my MC4 connectors had let moisture in. Cleaned everything up with some electrical contact spray and the difference was noticeable. Also worth checking the actual voltage your PWM controller is seeing on a clear day — mine was reading lower than expected and the panel mounting angle was the culprit. Tilting it even slightly south-facing made a real difference here in the north where the sun stays low. Small tweaks like that can squeeze a surprising amount more out of a basic budget setup. @Tom1981 what direction is your panel facing?