Our inverter and those of the few other people I know who have PV all have them indoors in their loft. All installed recently.
I doubt the installer would use spare ways in an existing consumer unit. Ours has a separate CU for PV and heat pump, and all 8 ways are used. There’s also an export meter which is separate from the regular import meter.
Ours is connected into the existing consumer unit, as it had plenty of spare spaces. The inverter is in the integral garage and we were told that they are no longer put in the loft.
As we have a heat pump we use Cosy Octopus. It’s not as cheap as an EV tariff but makes a lot more sense if you have a pump.
While we could pay just under 13p per unit and export it for 15p, it’s much greener to use your own power as much as possible, rather than importing and exporting. We didn’t actually consider payback at at, rather we did it because we felt it was the right thing for us.
In the summer we will be able to trickle charge the car from the solar during the day, fill the batteries and export what we don’t need.
I’ve just applied to the DNO increase our output limit from 3.68kWh to 6, which is the maximum the inverter can handle. It will be interesting to see what they say.
I’m at the estimates and quotes stage for PV and battery and all are planning the inverter and battery in the semidetached garage next to the incoming main and meter box.
PAS 63100 is, as your post says, an expression of best practice; it is NOT a law or a standard in the UK. These guidelines are not retrospective either.
We should not be misleading by describing it as a standard. If you read the link you posted it says it is not a standard or legal requirement.
A success due to amazing FIT tariff you are on!
Unfortunately, the game has changed. We too had Solar PV fitted on our old house in late 2011, qualifying for the high FIT tariff, index linked and tax free for 25 years. What a deal 
. We made ~£2,000 pa plus we used less electric. We also had an infinite battery effect as we had an old fashioned meter 
. However, we moved in 2020 so the new owner now benefits (it did pay for itself and more before we moved).
We have recently (Dec 2024) had a Solar PV and battery system fitted on our current house. It’s now all about the tariff and load shifting. Unless you have an EV the payback is nearer 7-10 years, depending on how the energy market develops over that period.
Have a look at the Tesla Powerwall 3. It’s fine outside (ours is in the attached garage though).
Absolutely.
However, they could potentially be incorporated into regulations in the future, especially if adopted by local authorities and housing associations who use them to set standards for installers; meaning there’s a possibility they could become more widely enforced through local regulations.
Stephen
They indeed might but they are still not standards required by anyone as yet nor indeed apply retrospectively.
Personaly I think they are overkill there are far more likely fire hazards in the home than solar inverters or batteries.
You are correct about the favourable FIT tariff but that was to encourage solar take-up.
My ROI on a then expensive installation is currently 227% or if adding the estimated electricity saving 261%.
So I was a trendsetter!
We’ve managed a measly 4.7kWh of generation today. Where is the sun? The forecast suggests it will put its hat on all day tomorrow. We’ll see.
ours today was 8.6 kwh, with 2.21kwh exported, yesterday was 5kwh and sunday 11kwh
I suspect the change away from putting the kit in the loft is less about fire and more about the kit’s weight. Firstly, the installer having to get it up there and secondly, the load it imposes on your house. Each of my 9.5 kWh batteries is 120 kg.
The other issue may be how the batteries perform in the cold. Many simply don’t. Often the charge rate is reduced below 10 degrees C and stops below 0 degrees. So positioning is key. An integral garage and near the consumer unit is about as good as it gets.
As always, try to be an informed customer and always use an installer with a decent reputation. Never go for the cheapest quote. There is a reason things are cheap.
A friend of mine trusted his installer. He ended up with his inverter and an undersized 6 kWh battery in his loft. The inverter app is junk, requiring loft access to change some basic parameters. As always, the app is your primary interaction with your kit. Make sure it suits you. The Tesla app used to be poor; it may be better now. GivEnergy is okay, but their kit has its issues. Trust, but verify.
Well, we had 12.7 kWh (from 15 455W panels, 11 S, 2 E, 2W). 4.8 kWh exported. Based in North Yorkshire!
We only switched the PV on in late December, so we are seeing it at its worst, which I think is a good way to do things. Our best day so far is 8.1, which was on 25 January. I’m hoping we will beat that 10kWh barrier tomorrow. It’s funny how addictive it can get; I’ve read posts on here where people get very geeky about the numbers and I couldn’t understand it, but now I most certainly do. It’s harmless fun, and optimising what you have can only be a good thing. We ran the whole house for £2.71 yesterday, heating, cooking, lighting, etc, which I think is pretty good.
I use the Netzero app with my Tesla Powerwall 3. The Tesla app is OK, but Netzero gives you more control if you want/need it.
That makes me feel a bit better about our 4.3kWh, but in N. Wales our expectations have to be lower. Low 30s on a sunny day in summer makes up for it.
We live in the sunniest part of the U.K. but you wouldn’t think so judging by recent weather. It’s gloom, gloom, gloom. I was talking to our installer yesterday and he said we’d get 50 to 60kWh at the height of summer. We shall see. I suspect he was trying to cheer me up.
Your supplier should have provided expected monthly output figures. These often come from reputable suppliers based on past performance. Mine have been close, albeit conservative. High temperatures reduce DC output, affecting July and August figures. May and June, if clear, are often my high months. Length of day plays a big part in daily output, as does the sun’s position in the sky. Yes, a sunny day in January is good; it would be 40% higher if the day were a bit longer. I specifically asked my supplier to focus on optimizing winter output, hence the use of oversized panels with microinverters.
The fun bit is when your house load is picked up by the solar before the end of the reduced rate at night (5:30 for me). I will need to wait until the end of April to see that from memory.
I don’t follow that penultimate sentence. I’m sure it would be fun if I could understand what you mean.
We’ve only had two full years with ours but 2024 was 4.5% down on 2023.
I’d put that mostly down to the wet summer!