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Looks like June with be a record month for solar:
Overall I’m £240 in credit over the last 30 days on Flux, with a 4.6kW array split east/west. The bulk of the income has been late afternoon on the high rate.
East West splits are king on flux. I can't have any west facing panels at the moment :/
East West splits are king on flux.
Definitely west facing. Ours is nearly twice that size but because it's SE facing its output has fallen right off by the time the Flux peak period starts. I keep wondering about adding more panels on the NW facing side so as to generate a bit more later in the day...
Ive had notice of my unit costs decreasing on flux but not my export rate.... whats it dropping to?
Numbers were in the same pdf attachment. This is South coast;
Electricity (Export) Current prices New prices
Unit rate - peak (per kWh) 35.925p 31.413p
Unit rate - flux (per kWh) 9.111p 7.177p
Unit rate - day (per kWh) 22.518p 19.295p
Oh just checked. Im on outgoing octopus so its fixed at 15p
we don't have an EV so most of the other tariffs are off limits at the moment. We would use the off peak hours to heat water and our ruinously expensive underfloor heating as well as putting 10kwh into the battery. we'd preserve the battery for peak-time which would save a few pounds a day, but a couple of units of sun in the daytime wouldn't touch the sides in jan/feb.
A longer off peak would be great for the heating, will see what sort of economy 7 plans there are available. Loss of export payment doesnt matter because there will be no excess.
Figures for June and the half year point.
5.4kWp array, south facing, in the SW. 20kWh of storage.
799kWh generated, 357kWh exported, 14kWh imported.
We’ve determined that we can run the electric shower at an 8kW draw without triggering the grid. Almost an equal split between battery discharge and generation. Nice!
Half Year Figures:
3152kWh generated, 926kWh exported, 649kWh imported.
We’ve only just begun getting paid for export, but had we been getting paid for the full year, we’d be almost cost neutral, but would still have had to pay £84 for the standing charge.
We've had a very disappointing last few days of June, ending with today with the lowest day of production since early April! The longer days made up for it, but June only just beat the much sunnier May.
What has been great though is Octopus Flux... every day since we've been on it our daily bill has been negative, even with charging the car. Hopefully it should continue to be good for another few months before we have to decide when to switch back to a normal off peak rate when generation drops and we start needing heating again.
We’ve determined that we can run the electric shower at an 8kW draw without triggering the grid.
As someone with a battery that will do a mere 2.6kw I am quite jealous...
We are a week and a half down at the moment and that's not going to change till at least the 10th. Very frustrating but nothing I can do about it. Supplier won't fit a bigger inverter if the current one is found to be dead.
I got £300 this month from flux, also with an ev. Only problem is it makes you neurotic about using electricity because you’re paying at least 20p/kWh for it.
I’ve largely stopped worrying about it now. The system seems to be well enveloped and covers 95-97% of our use case without significant thought. Only occasionally when cooking (hob, oven, dishwasher, etc) will I consider and stagger use. In the winter this will likely be more of an issue, but so far, very pleased.
I’m really happy that it looks like the system will generate more in a year than we use and thus has a slightly positive climate effect rather than just a neutral one.
If we ever have the money to replace my aging BMW Touring with an EV, I might have to also consider expanding the system. We have a quote in place to take it to 12kWp, but 50% of that increase would be north facing. By my estimates, that 6.5kWp system would generate about 3500kWh a year vs. 6000kWh from the south facing array.
It’s a far cry from the 14000kWh we’d need currently for heating but might just do an EV and partial heating.
Prices of panels are tumbling - just seen 500W for £150 inc vat.
I've got a flat-roof garage that could take a frame and maybe 6 south facing panels. They'd be sheltered morning and evening though. I'm already limited by the inverter at peak times in the summer so we'd need a new (bigger? additional?) inverter to get the full benefit. However, in the winter, the east-west split of the main array is pretty useless so these could make a big difference. Hard to work out the payback time with so many unknowns.
Anybody had my scenario pls: an existing PV array (on a FIT agreement) where I want to add a 2nd entirely separate PV array? Did it impact your FIT agreement?
The reason I ask is I've had 2 quotes from what appears to be two very competent contractors: Contractor 1 had no issue with this. Contractor 2 said categorically there was no way to have 2 arrays at one property and I would need to come to terms with the FIT agreement being ripped up. Everything I can find online sides with Contractor 1 but wondered if anyone else had this, or can guess at the driver as I don't see that it benefits Contractor 2 to take this stance.
Thanks in advance
you can do it physically - but you cannot have two MPANS
Your new solar would have to feed in past the existing generation meter for the FIT payments.
You wont be able to sign up for SEG payments on the new install as your MPAN is assigned to the FIT payments
ooh just had the total export value to the grid surpass my import valve for the first time since i got the panels. i dont know why this makes me happy but it does.
Also turn down and save on loop coming again but not sure how ill make anything this time as im not using much.
Anybody had my scenario pls: an existing PV array (on a FIT agreement) where I want to add a 2nd entirely separate PV array? Did it impact your FIT agreement?
I'm looking to do this.
You are not allowed to change the array linked to the FIT in any way - i.e. add to it or change panels. But you can have a completely separate array that does not touch the FIT array until after the generation meter. So the generation of array 2 can be fed into the same consumer unit as array 1 as the CU will be after the generation meter of array 1.
I doubt you can claim any payments from a second array - just benefit from the generation. So I would say that installer 1 is correct and installer 2 is kinda correct if he thinks you want the second array to feed into the house before the generation meter of array 1.
Thanks @trail_rat and @sharkbait, amazingly helpful. That's a shame but at least a constraint I can understand and work around (I didn't really expect much exporting anyway). I will put it down to me not articulating myself correctly.
While I have you! 🙂 - any views on installing pre-G99 approval (by throttling the export to below the current permitted limit) just to get the system up and running quicker?
I'm not sure you can do that. I think if the total of your potential panel generation is more than 3.9Kwh (or whatever it is that's allowed regardless) then you must go for approval - I presume your existing array is just under 3.9kwh so almost anything more would require approval.
(Obvs having 2 x 3kwh arrays could potentially put 6kwh into the network in the same way as a single 6kwh array could)
Its the inverter that is the limiting factor G98 = 3.6kw above that G99 is required, not the array. Not sure if its ever checked to be honest. Not so sure clipping is allowed as its easy to override
3.6kwh allowed.
there are fast track approvals though under certain circumstances .
Whos checking and whos knowing ?
Got you, thanks. Filing under "looks too good to be true so...". I'm keen not to put the contractor in a compromised position so will have a bit of patience
It depends on the DNO - SSE wouldn't allow our software constrained export (G98) and even after G99 approval, wouldn't approve the system for export until it was checked over by their own people.
It depends on the DNO – SSE wouldn’t allow our software constrained export (G98) and even after G99 approval, wouldn’t approve the system for export until it was checked over by their own people.
Whereas NPg were quite happy with my 7.3kW plus Powerwall system without any checking or witnessing.
Because I’m a senior manager at NPg (Head of Innovation when I applied, Head of Connections Design now) I kept my name out of the application as much as I could.
I had the installer apply and it went through very easily.
I did have to encourage them to give me the connection agreement for the export which my supplier wanted before they’d give me an export tariff.
Our process is being changed to make it easier (automatic hopefully) for the average customer who can’t just ring the MPAS Registration Manager direct.
Hopefully some of you will benefit from my problemette.
(We do learn and improve)
PS - I have had potential installers walk away from putting PV on my house when they found out I wanted it done properly and I knew what properly meant.
Why is the limit so low? I mean you can pull way more than 3.6 in and I'd assume the kit upstream is designed to handle high loads from a significant number of the end users connections.
It probably phase balancing
Apparently Musk / Tesla will be entering the UK energy supply business with Octopus style tariffs...
https://www.theguardian.com/technology/2023/jul/12/elon-musk-tesla-electric-supplier-britain
Wonder if Tesla will mind the Universal Supply Obligation, means they have to offer a Price Cap tariff to all including Prepayment customers.. I guess they want to ring-fence this to powerwall customers only?
Meanwhile: I have saved £660 in 6 months with my set up: 4.75kWp, 7,1kWh storage, MyEnergy Zappi, IPACE. Done 10k miles, total cost of elec: £199 home, £151 public charging
@djglover - what is the payback time like on a system like that if you are saving north of £1200 a year?
I guess they want to ring-fence this to powerwall customers only?
They're pretty tiny compared to all the Tesla car batteries, I'm guessing that his what they're aiming at...
Meeting peak loads spikes by discharging 10% of everyone's Teslas at the same time.
@igm it would be interesting if you could summarise some of the ‘done properly’ points?
It seems very difficult to work out who is half decent and correct!
@Matt - sorry dont know how mention..
about 7 years, paid £9988 in January. Assuming some energy price inflation. Installer forecast 3900 kWh generation for the year and already at 2,700.
Bad day for solar in the SW today. I have to go all the way back to March 8th for it to be this poor. 2.5kWh so far today.
win some lose some - all about the averages.
FFS, delayed sorting our solar as been getting a load of other work on the house, went back to it today only to realise the Scottish Government pulled funding for solar & battery a couple of weeks ago!
Still down here. Solaredge can't decide what the problem is 😢. Having to chase lots to get any kind of update.
Oh god, that's not good to say Solar edge seems to be pitched as the premium brand.
It goes to show how sporadic the after support is in the market generally, as if the whole industry seems consumed with installing as much as they can rather than balancing it with a good support network. Just my impression
Yeah it's not ideal. The lack of updates from the supplier is the most annoying bit. Even a call to say no progress would be better service instead of me needing to chase. I'm partially frustrated because I forgot to charge yesterday before their office closed and now have to wait till Monday.
One positive is the battery is charging during the cheap period so we are at least getting some benefit.
@nixie In practice the 3.6kW export limit is mainly due to the voltage rise caused by the export.
The system sits near the top of the allowable voltage range at no load and as demand (lights, cooking etc) is drawn down the system the voltage falls towards the lower limit.
If on a summer’s day your PV is pushing out export and the demand on the system is low then it can push the voltage over the upper limit.
Not always but it needs checking - hence there is a (fairly minimal) design requirement.
PS - if you want we can do the long discussion around ADMD and diversity of PV
@northernremedy - Borders between the edge of the panels and the edge of the roof, avoiding shaded areas, telling / applying to the DNO, discussing the order of the various bits of kit installed and where the CTs were to get the battery, EV chargers and PV to operate in the most cost effective way as well as safely.
That sort of thing.
I’ve found Solis (my inverter) to be very good and easy to contact, but LG - not so great. I’ve been waiting almost 6months for them to address a fault/problem with the battery management system.
Had the surveyor from Solar Together scheme out today, very helpful, answered all my questions, reckon it’s a go-er! Said the install would probably be turned around extremely quickly as well which is good.
The one question that slipped my mind was the possibility of using the battery as a back-up in case of power cut. It’s not a huge deal (we’ve only had 3 all less than an hour in the 3 years we’ve been here) but it would be nice if possible.
I’ve read (on here) that if your inverter is “grid-tied” (which it is - Solis S6) it’s a no-go, but this is at odds with other things I’ve read such as this ( https://www.solarguide.co.uk/solar-back-batteries-power-cuts#/ ) which to me reads that this function is purely a function of the battery? Which would be a Pylontech US3000.
Anyone shed some light?
Solis you can wire up some emergency circuits into the eps.
That's what we have.
You'll need an independent earth and most installers won't do it. It's hassle for them .
Watch your prices as well. Pylon batteries are cheap and prices of everything is coming down. Rapidly at the moment so careful comparing to prices quoted on here.
Panels - 400 watt is down from 250 quid at the start of the year to 140 right now....