Solar panels and battery - any real world reccomendations?
- Thread starter GinG
- Start date
Soldato
Must admit I like the look of the 20 panels and 10k battery at that sort of pricing, assuming cashflow isn't an issue.
No not really, my bank have a good rate atm and the repayments actually match my utility bill (which is an overpayment). So I think it would be costing me effectively 100-120 for 5 years on top of my usual outgoings and quite affordable (I'm basically giving the house solar over an EV through work scheme).
Something to mull over.
Soldato
Associate
The extra panels on the other roof are a no-brainer there. 60% more generation over the year for a third more cost. 8kW inverter too.
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Soldato
You'll also find with a dull cloudy sky the rear panels will generate the same as the front, with the right cloud cover it diffuses the light, effectively on those days you're actually doubling your generation, although it won't be lots it will all add up.
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Associate
My NW panels were generating 2-3kWh per day this way on occasion in January. No direct sun, but enough to make a big difference at that time of the year.
man you guys are making my wallet itch more - but the wifey isn't convinced - I'm going to have to give her some more hard data to back the spend up.
I don't think I can get away with sneaking the panels on there :/
I don't think I can get away with sneaking the panels on there :/
Soldato
Last year, our gas and electric, including standing charges came to -£400 (yes £400 profit!!!). That's a combination of FITS payments from our original 2015 solar install, export payments from solar (we installed more in February last year) that we only started getting paid for in April last year, and saving sessions.
This year won't be quite so good as rates have dropped, but currently we're £308 in profit.
Oh, and I'm in the process of adding another 6.5kWp of panels, which will bring our total to 15.535 kWp of panels for an estimated 13,729 kWh of generation for the year.
If you're staying in the house long term its a no brainer really, I'm sure others will tell you how much they are saving as well.
PS. Our gas and electric last year was estimated at around £3000, so you could say last year alone we saved £3400, this year our estimated cost for gas and electric is £2500.
PPS. If you removed gas from the equations, our profits would clearly be much high 2023 had £470 charges for gas.
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Soldato
I've had my system since late 22. Its 5kw inverter (but allows 10% over so its 5.5kw in reality), 5.7kwp, with 13kw of batts which should give around 11kwh useable but seems to be more like 10 real world.
In that time and bearing in mind that was pretty much peak pricing only 4 months I have had a net unit cost above 5 pence. (one month was 5.1p)
You need to bear in mind its influenced heavily by tariff and Octopus.
We get savings sessions that batteries let you make hay with, and the tariffs I used Go until April this year, went to agile and bills went negative and I am just back on Go.
As of end of July, which is just over 18 months I have "repaid" 26% of my investment. IE my bills have been reduced by that amount compared to the standard cap price each month.
Its a risk, Saving sessions in winter have changed each year and the later part of last year they screwed us a little with bidding. So thats far from guaranteed.
Powerups are postcode dependant and I am lucky to live in one of those areas.
Go/Int Go needs an Ev in theory but I never had to prove anything for Go. Intelligent Go however you will almost certainly be checked at some point, you need to pass a test session anyway at the start.
Free elec sessions are new from Octopus.
Bigger systems or those with high generation compared to usage tend to find Octopus Flux better. Especially in summer.
Export rates have become a lot more competitive since I started, ive had 4p 8p and 15p, although back to 8p on the Go tariff.
In that time and bearing in mind that was pretty much peak pricing only 4 months I have had a net unit cost above 5 pence. (one month was 5.1p)
You need to bear in mind its influenced heavily by tariff and Octopus.
We get savings sessions that batteries let you make hay with, and the tariffs I used Go until April this year, went to agile and bills went negative and I am just back on Go.
As of end of July, which is just over 18 months I have "repaid" 26% of my investment. IE my bills have been reduced by that amount compared to the standard cap price each month.
Its a risk, Saving sessions in winter have changed each year and the later part of last year they screwed us a little with bidding. So thats far from guaranteed.
Powerups are postcode dependant and I am lucky to live in one of those areas.
Go/Int Go needs an Ev in theory but I never had to prove anything for Go. Intelligent Go however you will almost certainly be checked at some point, you need to pass a test session anyway at the start.
Free elec sessions are new from Octopus.
Bigger systems or those with high generation compared to usage tend to find Octopus Flux better. Especially in summer.
Export rates have become a lot more competitive since I started, ive had 4p 8p and 15p, although back to 8p on the Go tariff.
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those seem a tad (£1-2K) more expensive than my install in feb this year
(10x 440 panels + 3.6kw inverter + 10kwh battery + bird netting etc = £8.3k all in)
who did you go with?
cool I'll reach out - I'm not in a super duper rush to accept a quote right now.
@reef since your roof is similar to mine, (mine is SW front NE back), does your analytics show the north roof generation clearly?
Associate
So far in 2024 I've generated 3597kWh on the SE array and 2634kWh on the NW array. The prediction for the NW panels on PVGIS is 2782kWh for the entire year and I got the NW panels on 10th January, so missed the first 10 days. They're outperforming the prediction in what has been quite a poor year with the weather.
You'll find the NE panels would peak in the morning and drop off as your SW roof picks up mid-morning onwards. You'll generate for longer than just having one roof done. Here's a trace from mine on 19th May - probably the only day this year closest to a perfect day. This is measured from the main inverter via the 2nd CT clamp so its negative, but you get the idea:
Yours would essentially be the reverse. In winter the NE roof wouldn't get any direct sun, but you'll still generate 1-2kWh a day. My NW roof made 35.0kWh from 11th-31st January.
Try this site (PVGIS) for a prediction of what you might generate on each roof: https://re.jrc.ec.europa.eu/pvg_tools/en/
I am now 5 days on from my install. I went with 10x 455w Aiko Panels, a 5kw Fox inverter and 12kw Fox batteries.
Barely had any sun, yet I've been able to be about 90% self-sufficient in that time. I have also benefitted from some free battery charging courtesy of Octopus (another free session soon today).
One day I paid 90p for electric, another day £1 (My usual costs before were between £4 and £6). I am just gutted I am not currently being paid for the export whilst everything gets set up for it and even more gutted I didn't pull the trigger on this before the summer.
I have to say i am VERY impressed with the Aiko panels. I had solar in my last house which was fitted over 10 years ago. It's clear just how much the tech has evolved over that time. I was peaking at 3.5kw of generation in cloudy conditions. Unbelieveable!
I am now counting down the days for summer 2025 when I plan to force charge overnight in the flux period for 13p, then export my excess in the day at 15p, then force discharge in the peak period for 26p.
Will see how I fair in the winter where last year I was spending £10-£12 a day.
Barely had any sun, yet I've been able to be about 90% self-sufficient in that time. I have also benefitted from some free battery charging courtesy of Octopus (another free session soon today).
One day I paid 90p for electric, another day £1 (My usual costs before were between £4 and £6). I am just gutted I am not currently being paid for the export whilst everything gets set up for it and even more gutted I didn't pull the trigger on this before the summer.
I have to say i am VERY impressed with the Aiko panels. I had solar in my last house which was fitted over 10 years ago. It's clear just how much the tech has evolved over that time. I was peaking at 3.5kw of generation in cloudy conditions. Unbelieveable!
I am now counting down the days for summer 2025 when I plan to force charge overnight in the flux period for 13p, then export my excess in the day at 15p, then force discharge in the peak period for 26p.
Will see how I fair in the winter where last year I was spending £10-£12 a day.
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Soldato
Winters the tuff one, late October to February really takes a hit, with December being the worst month for me, you need a nice cheap overnight rate and charge those batteries. Hopefully we'll also get plenty of "free" sessions to take advantage of.
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Soldato
Be interesting to see how many free days indeed
They seem to be running just a little less than powerups in frequency.
Powerups were just under 100 times in a rolling year from when they first started, spread pretty evenly I think lowest month was 5 times and highest 10.
So, and bear in mind this is very much an educated guess, we may see say 60-75 free sessions across 12 months.
They seem to be running just a little less than powerups in frequency.
Powerups were just under 100 times in a rolling year from when they first started, spread pretty evenly I think lowest month was 5 times and highest 10.
So, and bear in mind this is very much an educated guess, we may see say 60-75 free sessions across 12 months.
Soldato
Wrong thread.
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