Solar panels and battery - any real world reccomendations?

Maybe a moral here.

I was asked to give advice to a newbie. On a south facing roof close to us, it had been suggested that he installed 8 panels in a 4 x 2 portrait style. The panels were 400 Watts and about 1700mm x 1200mm.

I advised going for 9 in a 3 x 3 landscape. This was easily achieveable with a length of 5.1 metres and height of 3.6 metres. The 8 x 2 configuration was going to be 4.8 metres length by 3.4 metres high.

The installer told the client "Not worth going for an extra panel, its a waste of time" At the same time they were happy to try and upgrade the battery capacity.

Let us assume the new panel cost £200 plus an extra £150 for installing 3 rails opposed to 2. If the electricity is 35p/kwh and the extra output would be 420 KW/year, then the max saving would be £147/year. Even if the client was only able to use 80% of this, the annual saving is still £117.60p/year. On this basis the extra panel would pay for itself in less than 3 years ............just!!!!!!!!!!!

Cynics such as myself think the installer is so busy he just wants to rush through the job, and get on to the next one.

An extra 12.5% output for £350 does not come under my definition of "a waste of time".
 
4x2 will be quicker and easier to install for the installer. Basically, 4 rails vs 6 for 8 vs 9 panels. That is the only thing I can think of but it may not have been in the installers mind at the time.
 
Funny how once you get Panels installed you notice more and more the installations of various houses. was out on my bike at the weekend and spotted this ground mounted array which appeared to be on a movable jig, it was fairly sizeable being above the hedgeline, but looking at maps it looks like it moves, it was 4 or 6 panels in size.


also saw this in majorca on the north side of the island where the hills/mountain top must block a fair amount of the light during the day over the main house, but they'd managed to put them right at the bottom of their land overhanging a wall.


Both have given me some food for thought about looking at mounting vertical panels on my tilehung house on the south side with optimisers which would in theory provide real benefit over the winter from my shaded strings with no optimisers and probably not cost a significant amount more than retrofitting. I think I could get potentially 8 panels on in total, will speak to my installer to see what is possible.
 
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I'm not sure if it's mobile, will try to go past it again and get some better photos! looked pretty snazzy with quite a few arms to reposition it.
Fully charged did an episode on a system like that recently. They are not mobile, the whole idea is a that you can change the pitch every week to maximise the potential of the panels as the season changes.

I’ve also seen some that are motorised and rotate to follow the sun through the day.
 
Fully charged did an episode on a system like that recently. They are not mobile, the whole idea is a that you can change the pitch every week to maximise the potential of the panels as the season changes.

I’ve also seen some that are motorised and rotate to follow the sun through the day.
Yeah I assumed this was the case. Looked a pretty cool array
 
I'm not sure if it's mobile, will try to go past it again and get some better photos! looked pretty snazzy with quite a few arms to reposition it.

Now I'm on my PC I can see there are actually three sets in the garden. Looks like they may have 14 panels on the roof as well. Nice set up. Perhaps you should stop by for a chat, and get them to join the Overclockers PV Output team.
 
Folks has anyone signed up for Scottish Power's new SEG @ 12p /kwh?

Only pays out twice a year, but the rate is awesome. I could be on Octopus GO at 7.5p off-peak and exporting at 12p /kwh anytime...

They won't pay for brown energy (ie batteries) but it's not clear how they will exclude it given the smart meters will always sit upstream ie. next to the main fuse. In the example schematic they show a hybrid inverter, and presumably therefore OK.

"If you also have a battery storage system, we’ll need an image of the install schematic (or single line diagram) to show that the output from the batteries will not be measured by the export meter. This is due to it being classed as ‘brown energy’, which isn’t eligible for payments in our SEG scheme. The diagram must show where the smart/export meter sits in relation to the renewable installation, battery and grid."
 
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I was kind of hoping Octopus would up their SEG game because it's currently a travesty!

Flux should in theory be fine for the summer anyway, days are on the whole fairly good, even using it quite heavily would export some.
 
complete newbie to solar , did an enquiry on line after asking a friend how their solar was going, they were pleased with the investment (they are down south so their installer is not suitable for me). Property is an old slate roofed building, not listed and facing 205 degrees , is just off south. I would like an aesthetically pleasing finish to marry in with the existing building but appreciate it will never look quite the same as it does now. Decided to go for "all black" even though there is a slight performance drop.

The roof length is 16.2 although chimneys at either end encroach by total of 80 cam , and has a 31 degree angle , i worked out i have a full width of 350cm (maybe as low as 335, possibly 365cm) . The 3 installers who have visited have various quotes all for 16x 400 panels (6.6 total ) , and mostly for 3.7 inverters linked to 7 to 10KW battery. Two are within 100 pounds of each other at 12K . Having now read up and studied specs , i have some thoughts that i want as much solar as i can fit on the roof a 10K battery (yearly im at 7000 use is with EV) and min 6-7K inverter depending on where panels get to

I ve worked out with narrower panels (i ve seen some at 1.02m) , i can still get a row of 8 landscape , then would like to get 3 deep ie 24 panels

Questions i have

How close do panels fit , ie if 1016mm wide, when 3 mated together would be 3.05 metres or (a lot) wider ?

Any legal (England planning regs) around edge clearance , especially ridge and gutter clearances , any practical considerations, as with panels i’ve identified and based on calc upper and lower tolerances are quite tight

Looking at the Oct. flux tariff, what is max generating capacity allowed ( i seem to think 9KW?) , do other export tariffs have similar limits , is there a max i should for aim for or just keep it simple and get as much for self use as possible

Is there any portal where i can type in what i want , and get people to bid for it rather than getting full “sales pitch” on their systems every time i ask for a quote as i sort of know (for now!) the panels (REC or QCells) , the inverter (solax or Givenergy) and battery (Triplex or Givenergy)
 
They won't pay for brown energy (ie batteries) but it's not clear how they will exclude it given the smart meters will always sit upstream ie. next to the main fuse. In the example schematic they show a hybrid inverter, and presumably therefore OK.
T&C's
3.8. If your Export Meter records, but cannot determine the amount of, electricity exported from another source, you will not receive SEG payment until you install suitable metering to calculate the Exported energy from the source and capacity specified in your application. Once suitable metering is installed, SEG payments will be made from the date that we are able to verify the suitability of the metering. Payment will not be retrospective for any period where unsuitable metering was installed.
 
@Farnley

I can check the measurement between panels later, but from memory it's 20mm.

Usually you would have 300 or 400mm between panels and the edges of the roof, and the ridge.

Fit as many panels as you can, and make sure you get an inverter than can cope with the full amount of panels. Make sure you get bird protection.
You'll need to get G99 for over 3.6kW of panels, you can apply to the DNO yourself if you want to get a headstart on the installers.

Preferably use an installer that is MCS registered, it's a requirement to go onto Octopus Flux, which pays 25p and 36p for exports, oh and you can import for 20p for the hours overnight.
 
T&C's
3.8. If your Export Meter records, but cannot determine the amount of, electricity exported from another source, you will not receive SEG payment until you install suitable metering to calculate the Exported energy from the source and capacity specified in your application. Once suitable metering is installed, SEG payments will be made from the date that we are able to verify the suitability of the metering. Payment will not be retrospective for any period where unsuitable metering was installed.
So impossible with a hybrid inverter.
 
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