Solar panels and battery - any real world recommendations?

Ron-ski said:
The brackets which hold the rail to the roof hook are adjustable, as said above they should have adjusted the rail at the time of installing the panels.

Do you have bird netting, doesn't look like it in the pictures, without it you're likely to get pigeon's nesting under the panels, at that will drive you crazy.

PS A new roof doesn't mean it will be flat, as it would be highly unlikely they replaced the roof rafters.
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I have to ask - is this a big job to fix? I mean - assuming the scaffolding was back up?

Is it fair to say they likely have not carried out the work with reasonable care and skill?
 
Marakith said:
Thanks. If there isn't sufficient adjustment in the bracket can a longer one be used?
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I'd be very surprised if there wasn't sufficient adjustment, you basically have something like this.



and then the rails attach like this. Note the tiles should be notched out so they sit back flat, and the hook should have a small gap underneath so that no weight from the hook is exerted on the tile underneath.



I went to a lot of trouble to make sure mine was a flat as possible, with string lines across the rails.

 
Yeh you can either cut the back out of the tile or use use purpose made flashings.

The latter is much quicker to install, the former is cheaper as you supply the tile less and they break and maintains the look of the roof.

Some tiles are too thin (e.g. slate) to have the backs cut out so they’ll always use flashings.
 
Not sure if this has been mentioned here, but a very useful tool for working out the best tariff, although it doesn't take into account DNO limits and clipping etc, but its based off your actual generation, so that sort of accounts for it.

TimAndKatsGreenWalk

timandkatsgreenwalk.co.uk timandkatsgreenwalk.co.uk
 
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A few weeks ago the news came out that Huawei is leaving the UK market for inverters and batteries. Wonder if there's a way to buy discounted Huawei hardware now - any ideas where to look?
 
Probably nowhere, it's probably not widely known, so companies will still sell it as per normal. Wholesalers may lower prices so they don't get stuck with stock.

Why would you want to? I'm sure there is significantly cheaper options.
 
GivEnergy field services visit is booked for Monday 13th. I made it fairly clear to the girl on the phone, they must bring everything they need to ensure the issue is resolved during the visit and that a non-functional system since the end of July was unacceptable.
She understood.

Wish me luck!
 
nalla said:
so are they worth it and how many do you need
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I've quoted this in a more suitable thread.

Yes solar panels and batteries are worth it, my electric and gas (now removed) bills have been negative for almost three years.

As many as you can fit is the general consensus.
 
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Ron-ski said:
I've quoted this in a more suitable thread.

Yes solar panels and batteries are worth it, my electric and gas (now removed) bills have been negative for almost three years.

As many as you can fit is the general consensus.
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ok cool, there is a house behind me with 12, so i assume i can fit the same.
 
nalla said:
ok cool, there is a house behind me with 12, so i assume i can fit the same.
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Fit them on any roof space you have, including north. The installer may raise their eyebrow on north facing but they are just out of date with their knowledge, solar scales really well with size in all orientations.

Most of the cost of installation of pannels is paperwork and labour of the installation itself. The way to think about is pannels are cheap (£60 each), mounting systems are cheap and 2 decent roofers could install 12 in a day or 20 in a day so the labour cost is roughly the same. There will be some additional sundry items and scaffolding but the marginal cost of doing 20 instead of 10 is nothing like double, its more like 30% more.

North facing panels will produce about half that of their south equivilents but you are paying 30% more for 50% more generation, it is totally worth it.

As for batteries, the more solar you have, the less you need and unlike solar, batteries suffer from deminishing returns the more you add so you only want to add just enough. Any more will extend out your paypack period rather than reduce it so just don't go mad with sizing - 80% of daily use use typically enough.
 
Ron-ski said:
A very useful tool for calculating battery ROI, if you have the data, although primarily designed for heat pumps, but probably still useful without one.

TOOLS | Jonathan Tracey

www.jonathantracey.com www.jonathantracey.com

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I finally watched this and agree with the conclusion.

If you are paying commercial prices for design, installation and support, it's never going to be worth it if you already have enough for your normal usage. My own data backs this up.
 
b0rn2sk8 said:
Fit them on any roof space you have, including north. The installer may raise their eyebrow on north facing but they are just out of date with their knowledge, solar scales really well with size in all orientations.

Most of the cost of installation of pannels is paperwork and labour of the installation itself. The way to think about is pannels are cheap (£60 each), mounting systems are cheap and 2 decent roofers could install 12 in a day or 20 in a day so the labour cost is roughly the same. There will be some additional sundry items and scaffolding but the marginal cost of doing 20 instead of 10 is nothing like double, its more like 30% more.

North facing panels will produce about half that of their south equivilents but you are paying 30% more for 50% more generation, it is totally worth it.

As for batteries, the more solar you have, the less you need and unlike solar, batteries suffer from deminishing returns the more you add so you only want to add just enough. Any more will extend out your paypack period rather than reduce it so just don't go mad with sizing - 80% of daily use use typically enough.
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thanks for this, great advice.
 
The new Sigenergy inverter, battery and gateway are in and was commissioned today. In the end, rather than mess about keeping the existing 3.68kW string inverter for the NW roof, we merged the 2 strings on both the NW and SE roofs of the house and put them on an MPPT each. Being 11 and 12 panels, it gives a nice voltage around the 380v range for both, meaning it's right in the sweet spot for the inverter. The other two MPPTs are for the new panels on each side of the garage, one facing NE and the other SW. There's 6 x Aiko 510w on each side, so an additional 6.12kW in total. The Sigenergy batteries can output at around 4.5kW each, so it will run the 8kW electric shower nicely with a bit to spare. The installer has left room for another battery if we should need it in the future, but we have 18.08kW now (almost all usable) so we'll see how it goes over the winter. The heat pump is wired into the smart port of the gateway, so it's usage can be monitored in home assistant or the app. So finally I'm down to just one larger inverter and have power cut backup. Plus it's all in the garage, so I'm happier as there is not 160kg of batteries in the loft! They dug a nice deep trench under the block paving between the house and garage and put it all in trunking, so it's super tidy. He also wired it up so the EV charger is before, so no more issues with it sucking from the battery. I'm very happy.

As luck would have it, it has been one of the dullest, most miserable days for the first day. The garage roofs do have a bit of shading in the darker months, but the SW side for the most part will see the sun all year round. PVGIS suggests just shy of 12MWh per year, but time will tell.



We've left the cover off for the gateway as it's close to the garage door frame, but I might just put it back as I doubt I'll be in there much.
 
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