It's a 5kw inverter (or should be!) so I don't think it would be that, unless I'm misunderstanding the ratings?
Edit : it's a 3.68kw inverter, but that should still be enough I think?
Doesn't sound a million miles off what you might expect from 8x400W panels. Are they all connected in series as a single string?
My system (east/west facing) is still not hitting the target power of the panels but it's still March. Slope of the roof etc will all have an impact. The westerly panels are generating about 80% of their rated power.
You can get an idea of forecast generation each day if you set up your system (free) on Solcast. Though if you have things like shading from trees at certain times of day it won't include that.
Are the 2 x west facing panels on a separate string from the S facing panels (and can the inverter handle two separate strings)? if they are then 6 x 400W = 2400Wso it should about right.
If not they will bring the overall potential generation down.
My system (east/west facing) is still not hitting the target power of the panels but it's still March.
Same here but I still quite like an E/W split array - that said I'd giving some thought to an additional 2kW of South facing ground mounted panels.
The panels are all on one string with optimisers on the ones facing the other way (I think). The panels are each 455w, so 6x 455 is roughly where the clipping is today. If it's to be expected that's fine, the clipping just looked odd to me
The panels are each 455w, so 6x 455 is roughly where the clipping is today.
Obvs you'll never actually get the 455W per panel but although the flat line sounds a little odd the numbers are right which is hard to argue against.
I get a dome curve but E/W orientation is different as I get a bit more generation early and late in the day compared to a S facing array.
So that may be part of it - on a clear day your panels ramp up to max power over a shorter period of time, stays at max (flat line) and then drops quite quickly?
(Actually I would have thought the RHS of your curve should taper slower than the LHS due to the 2 west facing panel.)
Edit: maybe it's the software - I wonder how granular the data is 🤔
Well it's all installed! Went with Skylar in the end and very pleased with the result so far, scaffolding up a few days before, and down on the morning of good Friday. Install was 2 guys on day one, electrician did a long day but got everything wired everything up while the roofer was installing all the fixings on the roof. Battery and everything was ready to go but it was too breezy for the roofer to manoeuvre the panels around on the Wednesday so he came back the next day and mounted all the panels and plugged them in to the wiring before doing all the bird proofing. With the bank holiday out of the way we have just paid and are waiting on the paperwork so I can get the outgoing tariff and start figuring out the best way to maximise feed in etc. I will be trying the sigenergy AI via the app to see how that works out to start rather than messing about with settings all the time. Looking forward to much lower electric bills.
figuring out the best way to maximise feed in etc. I will be trying the sigenergy AI via the app to see how that works out to start rather than messing about with settings all the time.
If you're a bit geeky then Home Assistant is worth a look - I leave the charge and discharge up to Predbat which factors in typical daily use, solar forecast, car charging and stuff like Octopus Saving Sessions. It's not super difficult but is a step up from basic use of a PC.
Obvs you'll never actually get the 455W per panel but although the flat line sounds a little od
why not ? is that an east west split thing ? we regularly get the rated nominal power and in the shoulder seasons with adequate cooling regualrly see over the nominal by a fair margin. Ive got a 4.14kw array and have seen sustained 5.7kw a number of times.(with 3.6 going to the AC side and the remainder to the DC )
The solar thermal experiment appears to be going well.
i stuck 2 x Solfex fk250 panels on my dormer roof last year- which couldn't take PV due to differing angles crippling my existing PV strings.
I have a 250l Gledhill unvented solar store in the garage with twin immersions.
I was getting intermittent useful hot water through march - but for all of April ive not had to worry - a 250l tank at 80c lasts us a couple of overcast days with the output mixer next to the tank set at 44
Even on overcast days it keeps the bottom of the tank at a 20-30c (water feeds at 11c) so there isnt a massive differential between the top and bottom.
I'm into it for 2200 quid (and a few beers for a family member to commission the tank) and i calculated prior that with out hot water use (kids baths showers etc) we were spending 600 a year on oil just for the hot water..... +an electric shower.
Lessons learned - i should have got a twin coil tank , immersion isn't ideal - but neither is it crippling , however the heating's on anyway and because my boilers (currently) a combi sized to the ho****er needs its short cycling.
Its certainly showing its self to be a far more efficient way to heat water than using excess PV (of which i have very little) - 4sqm is giving about 20kwh equivalent PV energy - heres hoping it continues till october.
If you're a bit geeky then Home Assistant is worth a look -
Thanks, I'll have a look at that. Submitted all the paperwork to Octopus today so just waiting until they set up the export tariff.
I reckon the Octopus saving sessions aren't worth the faff any more. This evening's session would've netted me about 50p.
I’m getting closer to switching to something like Eon Next, with the longer and cheaper overnight. Octopus’ decent service is just keeping me hanging on!!
FYI Spain has had its first ever weekday 100% renewable grid. NESO think the uk could have a summer of lower demand than the 2020 lockdown potentially, with so much renewable solar going in to the grid.
I didn't bother with the saving session the payment is now so derisory it's not worth discharging the battery for.
I know it's the regulator that's stipulating the lower payments but surely someone's seeing the lower participation hardly encouraging people to use less at peak
I’m getting closer to switching to something like Eon Next, with the longer and cheaper overnight. Octopus’ decent service is just keeping me hanging on!!
FYI Spain has had its first ever weekday 100% renewable grid. NESO think the uk could have a summer of lower demand than the 2020 lockdown potentially, with so much renewable solar going in to the grid.
Eon aren't Octopus when it comes to CS but they get there eventually. I'm topping up batteries at 6.7p 0000-0700 and exporting at 16.5p during daylight, somedays I've been exporting just after 7am
Most of my grid use is importing at cheap rate. The SEG payment is a bit antiquated only get paid every 3 months and you have to send readings in, since march I've exported 840kwh and imported 230kwh . I dont brown export.
Long-time considered solar panels here but want to take the leap this year.
Who's best to consider - big suppliers (like Octopus) or local installers?
My recommendation is a long time established local installer, if i was doing it again
I found a national supplier for mine, who went bust... so in the event of any issues i'm not quite sure what i will be doing
I guess at least with Octopus etc you will have a point of contact for ever more
If you want it doing, get on it now i would say
Interesting observation.
May 2025 has given me just under 100kwh more than any previously recorded max from any month since 2021 install.
Answering my own question. We've now been on intelligent flux for a few months. So far earnings are just under double the spend each month. I think though it could be even more intelligent (e.g. let us use battery power in mornings when it's a sunny day and they will likely be full again way before needed). Mostly though I'm happy at moment. If the trend continues like currently I suspect we will spend very little on electric at all
We’ve had an incredible April and May in North Yorkshire. Been brilliant!
Same story down South. For us March 25 generation beat April 24, April 25 beat May 24 and May 25 is on track to beat June 24.
Solar and battery is working well so far. Only had export set up this month and have exported 666kWh Vs 495kWh use, over 99% of the use is off peak charging of the battery or car overnight. On Octopus for the car and export so 7p charging and 15p export.
Anyone care to comment on this? It's a scheme offered by EDF.
Why only 6 panels? The panels are relatively cheap and if they are there with scaffold and doing all the wiring etc may as well do more if you can. 19 panels were fitted in basically a long day by one electrician and one roofer. Panels had to go on day 2 as it was too breezy on the first day but all the rails were fitted. Peak rate for usage is quite high and you won't be generating much at that time of day. Speak to the guys at Skylar Solar, they were very good for our system and have a good reputation.
Why only 6 panels?
Guessing that's all the front of house roof will fit looking at satellite image. What's your daily kwh usage? I'd increase the battery storage if you have space to, I had 10kwh battery storage, my daily in autumn/winter is just over 10kwh, recently I added another 5kwh this gives me a bigger range of stored power.
Once you have solar/battery this opens up access to cheaper rate electric to store up battery at night, useful in winter months when not generating much if any. Also get a seg account set up to get paid for and unused generation
My export payment for last 3 months was £264, thats just green export. Seen many boasting about their brown exporting ££££ I'm guessing it won't be long before there is a clamp down on that. Buy at 7p sell for 16.5p....
Seen many boasting about their brown exporting ££££ I'm guessing it won't be long before there is a clamp down on that.
This is what our tariff deliberately offers. Import and charge when grid demand is lower so it can be export at high demand. All controlled by the supplier.
All controlled by the supplier.
That's a completely different set up when the utilities co are controlling your set up, why you grant them access is beyond me but not something I'd allow.
That's a completely different set up when the utilities co are controlling your set up, why you grant them access is beyond me but not something I'd allow.
If the utility knows when it can access your battery for export then it becomes dispatchable and is worth more to them. Which is why they can in turn offer the consumer a better rate.
why you grant them access is beyond me but not something I'd allow.
It's a trade off isn't it. I'd rather have the control but on present evidence giving the control will reduce our bills. Can revoke access at any time I please.
I’d at least look at the bigger battery option or at least how easy it is to upgrade it and whether you’ll need a bigger inverter. The signergy kit Sklyar install has modular batteries where you can just add another to the stack and tell the system with no rewiring etc. Since we got our export sorted this month we have run the house off the overnight EV cheap rate topping up the batteries and exporting the excess solar during the day.
Apologies if this isn't meant to be here, I'll start another thread if that's deemed better.
Anyone here familiar with the rules around replacing & adding to the system when you're on a FiT tarif? Our inverter has failed (I believe so anyway, someone coming to look at soon) and we have around 8 years left on the FiT scheme. I'd like to replace the Inverter with one that is battery ready, and, ideally add some batteries too so that when FiT finally ends we aren't left wanting to change inverters again. Obviously we dont want to loose FiT payments entirely (for reference approx £1800 p.a) but I've read that these changes are possible without loosing the generation payments. It would affect export payments as we'd no longer get the 50% asssumed export and it would be metered instead.
The companies I've contacted so far about fixing/replacing the broken inverter are saying that if we change anything to a part that isn't like for like that we'd loose our FiT payments.
Can anyone confirm or deny this?
Anyone here familiar with the rules around replacing & adding to the system when you're on a FiT tarif? Our inverter has failed (I believe so anyway, someone coming to look at soon) and we have around 8 years left on the FiT scheme. I'd like to replace the Inverter with one that is battery ready, and, ideally add some batteries too so that when FiT finally ends we aren't left wanting to change inverters again
I'm fairly sure you can't - well you can but it might be seen as an upgrade which isn't allowed and you'd probably lose your FIT entitlement - if you think about it the batteries would reduce what you export which goes against the FIT rules.
You can replace the inverter but not with a battery ready one. With all the money you're making on the FIT payments you can afford to buy a new inverter when your FIT term ends 😉
It would affect export payments as we'd no longer get the 50% asssumed export and it would be metered instead.
That's not a great loss though really is it? (compared to the generation payment)
..... I mean, you could change to a hybrid inverter and hope they don't notice your export has changed or that they don't come and check your system in the next 8 years - but whether you think the risk is worth it is another matter!
Have you got room for a separate array? That could be anything you like if it's not linked to the existing array in any way.
@doomanic Take 5mins and pop your details into BOXT to see how much they'd charge, when I did this it was cheaper and I then used it to get EDF/CS lower. BOXT actually spec'd a larger inverter the 5kwh one which then got upgraded on the OG quote, I'm glad I went for it now over the 3.6 as tea times can see periods of above 3.6 and this is where you'll then import at the high rate between 1600-1900.
Between agreeing the contract and install I then added a second battery for £1500.
DM me if you'd like any more info about my experience, but overall, happy with the experience and install, it then only took 3-4 months for me to stop watching the sunsynk app to check generation and export figures!
I've had a couple more quotes. I now have a selection from £6400 (7 panels, 3.2kW Fox inverter and 5.2kWh Fox battery) to £10.5K (7 panels, 3.6kW GivEnergy inverter and 5.3kWh GivEnergy battery). Obviously they all say their kit is the best and the GivEnergy supplier was very rude about Fox when I pointed out his kit was £4k more for no obvious benefit. Is there an independent site that reviews this stuff?
Also, if anyone can suggest an installer they've used I'd be grateful.
Take 5mins and pop your details into BOXT to see how much they'd charge, when I did this it was cheaper and I then used it to get EDF/CS lower.
£6449 for my requirements using Sunsynk inverter and battery.
Anyone here familiar with the rules around replacing & adding to the system when you're on a FiT tarif? Our inverter has failed (I believe so anyway, someone coming to look at soon) and we have around 8 years left on the FiT scheme. I'd like to replace the Inverter with one that is battery ready, and, ideally add some batteries too so that when FiT finally ends we aren't left wanting to change inverters again. Obviously we dont want to loose FiT payments entirely (for reference approx £1800 p.a) but I've read that these changes are possible without loosing the generation payments. It would affect export payments as we'd no longer get the 50% asssumed export and it would be metered instead.
Replacing the inverter wouldn’t invalidate the FIT as the generating capacity is not being altered. This wouldn’t even need notification. Adding a battery would require notification, but would not necessarily invalidate the FIT as , again, the generating capacity remains unaltered. FIT is tied to generating capacity. If that capacity is unaffected by a change, it’s okay - even the battery should, in theory, be okay as you’re not altering generating capacity. Export, sure, but that’s not what the FIT scheme is constrained by.
I've had a couple more quotes. I now have a selection from £6400 (7 panels, 3.2kW Fox inverter and 5.2kWh Fox battery) to £10.5K (7 panels, 3.6kW GivEnergy inverter and 5.3kWh GivEnergy battery). Obviously they all say their kit is the best and the GivEnergy supplier was very rude about Fox when I pointed out his kit was £4k more for no obvious benefit. Is there an independent site that reviews this stuff?
Also, if anyone can suggest an installer they've used I'd be grateful.
Very happy with my Fox setup and would have another one. Make sure the batteries are equipped with heaters, but I believe nearly all the new ones are.
Make sure the batteries are equipped with heaters, but I believe nearly all the new ones are.
They are, but will be installed indoors.
Very happy with my Fox setup
How do you find the app? Gets a bit of slating online.
Export, sure, but that’s not what the FIT scheme is constrained by.
We'll not exactly.... 50% of my generation is deemed as export (and I get paid for that) which would obvs change if I had a battery.
Maybe they're not bothered about that though?
if anyone can suggest an installer they've used I'd be grateful.
Whereabouts are you? Are you buying the kit and expecting to hand it to an installer? Most will have a preferred brand or two and if for instance they usually work with GE they might not fancy installing Fox.
Oh and very happy with GE kit here.
How do you find the app? Gets a bit of slating online.
I’m not actually using the Fox app. Instead mine is connected to Home Assistant via RS485, but there’s an alternative to the Fox app that most people use anyway (Energy Stats).
Has anyone here gone for an install via Octopus with interest free credit?
