Solar panels and battery - any real world reccomendations?

Yep, potentially 60-65% more generation per year for only £2000 more, plus a bigger inverter which would maximise generation on the other panels. Absolute no-brainer, could be 75% more generation annually for 25% more cost.

No surprise to see them "recommend" the quote with a 3.68kW inverter. Easier for them I guess, but worse for the customer in most cases.
Would the 6k inverter be enough?
 
Installing just a battery and inverter is really straightforward, only thing that may complicate it is if the DNO limit the export power.
Looks like you can go 3.68kw no problem? If the unit can be limited to that.
Need to speak to electrician contractors at work and see if anyone is willing to do it
 
Looks like you can go 3.68kw no problem? If the unit can be limited to that.
Need to speak to electrician contractors at work and see if anyone is willing to do it
You’ll need a G99 as you already have a solar inverter.

It’s G98 notification for a single inverter below 3.68kw. Anything more needs a G99 which is permission from the DNO to connect.

Without MCS you'll probably have to pay Octopus to be able to export as well.
They already has MCS from a solar installation.

You don’t get MCS for batteries anyway, it just covers the solar panels themselves.
 
Looks like you can go 3.68kw no problem? If the unit can be limited to that.
Need to speak to electrician contractors at work and see if anyone is willing to do it
IIRC you already have solar and an existing MCS certificate - so no problem exporting.

If you already have solar then you will already have an export allowance.

You have the legal right to export up to 3.68kW, this can be installed, commissioned, and then the DNO informed by a G98.

Now if you add an AC connected battery, which will mean another inverter, then you are increasing your generating capacity, this will highly likely take you over your export allowance, hence you will need to do a G99 application, prior to commissioning.

I had a 3.68kW FITS system installed in 2015, so when I added more solar and batteries I had to apply for a G99 for 11.68kW, that's my original 3.68 plus the new inverter's 8kW capacity.

I highly recommend you get the G99 before you buy anything, you may not be able to get the full capacity, and then you need a G100 certified system to limit export, or reduce the new inverter in size.
 
@Ron-ski seeing as you have actually done one, isn't a full installation diagram part of the G99?

I am sure I read they (DNO) are supposed to know what generation is on site and basically where, so that I guess they don't have to inspect the site if dealing with an issue.

I know mine had a full diagram but it could have been my installer going overboard.
 
What @Ron-ski says is correct.

I have an original fit system, installed in 2012, 3kw. MCS certified. In 2021, or might have been 2020 I added a battery, didnt tell anybody. Just fitted. Last year I added some more solar. I did my G99 application and was told the max size inverter I could install was 6kw. They were giving me a maximum potential export of 14kw (original 3 + battery 5 + new inverter 6).

Fortunately the Solar Edge inverter I've installed can be 200% oversided on panels....and at the moment it's got an east / west array into it so in the future I can add more panels and not be losing out too much.
 
seeing as you have actually done one, isn't a full installation diagram part of the G99?
Yes, you need to provide a site layout plan, I just did like an aerial view of the ground floor of the property and noted where items were installed, its pretty basic.

You also need to provide a system schematic, I went well OTT here, with the recent changes to the system I do need to update that, but no need to inform the DNO as my generating capacity hasn't changed, in that I still only have the ability to export a maximum of 11.68kW.
 
No surprise to see them "recommend" the quote with a 3.68kW inverter. Easier for them I guess, but worse for the customer in most cases.

I probably wasn't being clear - I believe he was recommending less panels if I had access to Octopus Intelligent Go, as the battery would cover most of my days usage anyways.
 
as the battery would cover most of my days usage anyways
Its highly likely that the north facing panels are a big no no for them, a lot of solar installers are only just coming around to east/west panels.

Its also not about covering your own usage, you can easily cover summer, but winter that's extremely unlikely, so the more panels helps in the winter, but more export in the summer means more cash in the bank to cover that winter usage.
 
I suppose there is another factor in N / mainly north facing panels in that they are far more likely to need a clean to remove moss.
I mean its not going to be super regular but likely to be a risk factor.

Also agree in regards winter being the key, thats when every little bit of extra gen feels good.

Always need to also remind people that unless they have an EV of some description there is a risk with Go.
 
Time will only tell how my new panels cope with moss/lichen etc on a WNW roof, but all sides of my roof have about the same amount of moss etc.

Moss will grow anywhere it can get moisture some basic nutrients and some light.
Its no different to any other plant.
But it copes better where there is less direct light.

My NW shaded roof (the one on the extension so is shaded by the house itself) gets covered in moss yearly - so cleaning may well end up being a factor

Even if it happens the other string will be fine. And by all accounts modern panels cope ok with partial issues anyway.
I would expect it to start along the bottom lip and get a foothold and then slowly work its way up.

Panels can also get lichen anyway so a medium term amount of maintenance should probably be planned anyway.
Like 10 years sort of timeframe.
You may get lucky and not need any, you may get unlucky and find you need it.
 
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