Solar panels in Scotland - worth it?

Vitor

Those figures do not look silly, but I would treat the seven-year payback as optimistic rather than impossible.

A 4.2kWp system producing around 3,500kWh a year in central Scotland is plausible for a clear, south-facing roof. Home Energy Scotland says the average Scottish solar array is about 4kWp and costs around £6,500, with typical payback around 8 to 12 years. Energy Saving Trust gives Stirling examples of roughly 12 to 15 years depending on occupancy pattern, so location does matter.

The key issue is not whether you generate 3,500kWh. It is how much of it you actually use. Electricity you use yourself is worth about the import price, currently 26.11p/kWh under the July to September 2026 Ofgem cap average. Exported electricity is worth whatever SEG/export tariff you choose, and SEG payments are not automatic. You normally need MCS certification and a smart meter.

Very roughly, if you generated 3,500kWh and used 40% directly, the panels might save/earn around £600 a year depending on export rate. That makes £6,250 look more like a 10-year payback than seven. With a battery, you may use more of your own solar, but the battery’s extra £3,750 cost has to be justified by the difference between import and export prices. If export is decent, the battery case becomes weaker unless you also use cheap overnight charging, have an EV, heat pump, or high evening demand.

On the 9 versus 14 panels point, I would not guess. Ask both firms for the roof layout, panel dimensions, fire/access margins, inverter size, expected annual generation, shading report, and whether any DNO approval/export limit is assumed. Fourteen panels may be perfectly possible, or it may be an optimistic desktop design.

My instinct: panels probably make sense on that roof; the battery needs much more scrutiny.

FFHillbilly

https://forums.moneysavingexpert.com/discussion/comment/82033584#Comment_82033584

the more wars that kick off in the meantime will reduce the payback period even more

Savvy_Sue

@Vitor said:

On the 9 versus 14 panels point, I would not guess. Ask both firms for the roof layout, panel dimensions, fire/access margins, inverter size, expected annual generation, shading report, and whether any DNO approval/export limit is assumed. Fourteen panels may be perfectly possible, or it may be an optimistic desktop design.

And I must admit that my question regarding the discrepancy in the no. of panels was "but are they the same size in each quote?"

ludditeJazz

@Herzlos @Qyburn @Heedtheadvice interested to read your advice to @Herzlos about his install. Dunno if this is of interest but I'm a journalist at the Financial Times, trying to understand whether/ how much more expensive these kinds of projects are in Scotland than in England and why that might be (I also own PVs and home battery in my London home and am installing same for my Mum in Hampshire).

From what I can see so far: Herzlos quote - 9-panel / 4.2KWp system with/out about 11kwh of FOX battery, £6.25k/ £10k. Recent comparable UK quote I recently saw was: 14x Aiko panel, 11kwh of FOX (Ep12) £7.5k including bird mesh/ scaffold/ MCS cert etc.

On the face of it that's quite a gap - 33pc more expensive. Maybe that's not the whole picture. I'd be interested to learn what kind of quotes you were getting and for what - no need to share them here if you'd rather not, just DM me here or hugo.cox@ft.com. @QrizB you mention Scottish installer market differs, I'm interested in how/ why.

Anyway, very interested to hear your thoughts. Thanks, Hugo

QrizB

For anyone who's wondering about speaking to a FT journalist, they're the same person who co-authored this article from April:

https://forums.moneysavingexpert.com/discussion/6664427/our-very-own-qrizb-gets-a-mention-in-the-ft

And I don't deserve any of the credit but I'm happy to bask in the glory for now 🤣

ludditeJazz

😆 thanks @QrizB; as you can see I've learned the hard way, and am learning still - onwards and upwards!

QrizB

@ludditeJazz regarding the Scottish market, I don't have any definitive insights. However prices always seem to be higher up there.

My assumption are that a combination of:

• Lower population density outside the Central Belt, when compared with rural England or Wales (for example the Highland council area has half population of Cornwall in seven times the area); and
• The lower solar potential at those latitudes (roughly 20% less in Thurso than Swindon);

… results in lower demand, fewer installers, higher costs (longer travel times etc.) and a more expensive marketplace.

It would be an interesting exercise to query the MCS database of installers and see how many Scottish firms there are compared to England and Wales.

Qyburn

https://forums.moneysavingexpert.com/discussion/comment/82095670#Comment_82095670

My experience was that the "shouldn't cost more than" comments on here simply waste time chasing after the impossible. For example an installer referred from this forum started off at around 30% more than the "shouldn't cost more than" figure promised on here, and then after wasting yet more time it turned into a no bid. Realistically you need to turn to installers actually working in your area. Forget pricing from elsewhere.

Herzlos

https://forums.moneysavingexpert.com/discussion/comment/82095670#Comment_82095670

I was going to say pretty much the same thing. Lower population density and presumably less demand for solar due to lower light intensity making the pay off period higher.

I did also notice that Octopus (who are where I looked initially) stopped covering Scotland for installations (and referred to partners instead), and that I was lured in by a finance offer that didn't apply to Scotland either (though that wasn't obvious from the site). I don't know why those differences would apply as they seemed to have a few partners covering Scotland and we'd be the same from a financial POV.

Curiously whilst there seem to be tons of adverts for solar (thanks tracking ads!) the 2 companies I found came from quite a distance away - nearer the coast into the central belt.

As it happens we've pulled the trigger on company 2 to install in a few weeks time, though after someone came out we decided only 13 panels would fit.

Edit: For comparison, the 13 panels (6.05kWp) is expected to generate about 4700kWh/year, we're expecting to consume 3100kWh directly and import/export about 1600kWh each. I assume if you had the same panels in Dorset instead of Glasgow it'll produce notably more power.

ludditeJazz

Sorry to delay, these are very useful, thank you; I'll take a closer look and let you know.