Anyone else noticed their energy bills going up even with solar this winter?

Yeah, this winter has been a proper eye-opener honestly. Even with my 4kW array on the garden office and a decent Victron setup, the bills on the main house haven't dropped as much as I'd hoped. The sun just isn't there in December/January — obvious in hindsight, but still stings when you see the actual numbers.

The issue for me is that the solar is doing a decent job offsetting the office loads (monitors, heating, lighting), but the house itself is pulling more in winter — heat pump running harder, lights on earlier, the usual. So the net saving is much smaller than the summer months.

A few things I've noticed:

• Standing charges keep creeping up regardless of what you generate
• Cloudy weeks here in the Midlands basically wipe out any meaningful harvest
• My Fogstar batteries are cycling less simply because there's less to store

I'm seriously considering whether a second smaller array on the south-facing house roof would help balance things out, or whether I'd just be throwing money at a problem that's fundamentally a seasonal mismatch.

Anyone else finding the standing charge increases are basically cancelling out whatever solar savings you do manage in winter? Feels like the goalposts keep moving. And has anyone gone down the route of pairing with a proper grid tariff like Octopus Flux to at least use stored energy more cleverly during peak times?

Would be good to hear from others — especially if you're in the north where I imagine daylight hours are even more brutal right now.

@TonyLee not surprised tbh. Winter solar in the UK is basically decorative at this point 😅

I've got panels on my static caravan and the generation figures November through January are genuinely depressing — we're talking maybe 15-20% of what I'd expect in June. Short days, low sun angle, and half the time there's a layer of muck or frost sitting on them anyway.

The real killer people don't account for is heating load. Your consumption rockets exactly when generation collapses. It's almost comically bad timing when you think about it.

Have you actually checked what your array is producing vs what you're assuming it's producing? Victron's VRM portal will show you the truth pretty brutally. Might not be what you want to see but at least you'd know where the problem actually sits.

@DODGuy harsh but not entirely wrong 😄

Thing is though, the issue isn't just generation — it's consumption creeping up without you noticing. I found this with my shepherd's hut setup last winter. Added an oil-filled radiator "just for the cold snap" and it absolutely destroyed my battery reserve overnight.

Worth checking if you've got any phantom loads or heating that's kicked in automatically on the main house. Immersion heaters are notorious for this.

Also — angle matters massively in winter. I tilted my array steeper in November and picked up a noticeable difference on the clearer days. Not a silver bullet but every bit helps when you're scraping 2-3 peak hours.

The bills thing is real though. Grid standing charges alone are painful even if you're barely drawing anything.

@TonyLee had almost the exact same reckoning last January on the narrowboat. The sneaky culprit nobody mentions is thermal load creep — you're not using more appliances, you're just using existing ones longer because everything's fighting cold.

My Victron Cerbo logs told a brutal story: same devices, roughly 40% more runtime October vs July.

Couple of things that genuinely helped:

• Time-of-use shifting — charge batteries on cheap-rate overnight electricity (Octopus Flux changed my life)
• Proper battery insulation if it's in a cold space — LiFePO4 efficiency drops noticeably below 5°C, ask me how I know 😬
• Ruthless audit of standby loads — my inverter was idling at 25W doing absolutely nothing useful

The 4kW array isn't the problem. The problem is winter is basically an energy audit you didn't ask for.

@TonyLee same issue on my narrowboat last winter. What nobody's told you yet is that your Victron kit will show you exactly where the power's bleeding out if you actually dig into the VRM portal properly. Most people don't bother.

Pull up your consumption graphs by hour and you'll spot the problem pretty fast. Mine turned out to be the inverter itself sitting in idle draw overnight — pointless when there's nothing to run.

Also worth checking whether your 4kW array is actually doing anything useful before 10am and after 2pm in December. Spoiler: it probably isn't. You're essentially running on battery overnight and refilling it barely in time before the next evening.

What's your battery capacity? That's usually the real limiting factor in winter, not the panels.