Got a quote at last, and I'm inclined to like it.

Bear in mind that the roof of my cottage and the adjoining ones all have
chimney stacks above the ridge and the aspect is at right-angles to the
ideal south-facing one, hence larger number of panels than would be ideal.

Quotation to include:
Supply & install aluminium rail to the roof of the property.

Supply & install 10 x Trina 425W black pv panels horizontally to the
newly installed rails at the front of the property & vertically to the
newly installed rails at the side of the property to create a 4.25KW system.

Supply & install 10 x Tigo Optimisers to the panels to improve
performance due to shading.

/Shading, if caused by leyland cypress, is being turned into solid
fuel.../ (My note)

Supply & install bird block to the perimeter of the solar array.

Wire from the pv panel positions into the top floor room of the house to
the proposed position of the inverter and battery storage.

Supply & install 1 x Givenergy 5kw hybrid inverter in the the top floor
room of the house.

Supply & install 2 x 5.2kw Givenergy batteries to create 10.4kw of storage.

Wire from the hybrid inverter to the meter position located in the
kitchen on the ground floor & connect 1 x CT clamp to the mains tails of
the load side of the supply meter.

Install 2 x DC rotary isolator to the PV strings beside the inverter.

Supply & install 1 x BS7671:2018 amendment 2:2022 compliant consumer
unit beside the inverter to house the circuit protective device and
solar pv ancillary equipment.

Install 10mm 3 core SWA from the existing house consumer unit up to the
newly installed consumer unit at the inverter position.

Install 1 x 32A rotary isolator at the mains intake position & 1 x
generation meter.

Connect all cabling to the inverter and battery storage.

Commission, test, inspect & handover to client.

Subtotal £11,947.81
Total £11,947.81

Scaffolding has been allowed for in this quotation for the duration of
the works.
Once the work has been completed, an electrical installation
certificate, part p certificate & MCS certificate will be issued1 / 2l

Any comments from cognoscenti would be welcomed.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

RustyHinge wrote:

> Any comments from cognoscenti would be welcomed.

Knowing the location and orientation of Rusty Acres, assuming they fit 6
panels on the front roof and 4 on the end wall, and that you chop down
trees to avoid shading on the end wall, in an average year your total
generation should be about 3300 kWh, assuming your supplier's price
comes down today to 29.5p/unit that's about £973 worth per year (likely
reducing slowly as prices return towards normal).

In the best 3 months, you'd be able to fill the battery from empty most
days and have maybe 5kWh left over, either to use "live" during the day,
or to export (most suppliers have a pittance SEG rate, one or two pay
decent)

In the worst 3 months you'll only be able to half-fill the battery most days

The in-between months will, of course, be in-between, probably not too
bad a balance year-round, depending on how you can use it during
daylight/darkness hours.

What's your typical annual electricity usage in kWh? Assuming (sorry)
you remain largely housebound, how much would you use during day and night?

12+ year payback, assuming you can maximize usage.

Perhaps post this on uk.d-i-y?

RustyHinge <rusty.hinge@foobar.girolle.co.uk> wrote:
> Got a quote at last, and I'm inclined to like it.
>
> Bear in mind that the roof of my cottage and the adjoining ones all have
> chimney stacks above the ridge and the aspect is at right-angles to the
> ideal south-facing one, hence larger number of panels than would be ideal.
>
> Quotation to include:
> Supply & install aluminium rail to the roof of the property.
>
> Supply & install 10 x Trina 425W black pv panels horizontally to the
> newly installed rails at the front of the property & vertically to the
> newly installed rails at the side of the property to create a 4.25KW system.
>
> Supply & install 10 x Tigo Optimisers to the panels to improve
> performance due to shading.
>
> /Shading, if caused by leyland cypress, is being turned into solid
> fuel.../ (My note)
>
> Supply & install bird block to the perimeter of the solar array.
>
> Wire from the pv panel positions into the top floor room of the house to
> the proposed position of the inverter and battery storage.
>
> Supply & install 1 x Givenergy 5kw hybrid inverter in the the top floor
> room of the house.
>
> Supply & install 2 x 5.2kw Givenergy batteries to create 10.4kw of storage.
>
> Wire from the hybrid inverter to the meter position located in the
> kitchen on the ground floor & connect 1 x CT clamp to the mains tails of
> the load side of the supply meter.
>
> Install 2 x DC rotary isolator to the PV strings beside the inverter.
>
> Supply & install 1 x BS7671:2018 amendment 2:2022 compliant consumer
> unit beside the inverter to house the circuit protective device and
> solar pv ancillary equipment.
>
> Install 10mm 3 core SWA from the existing house consumer unit up to the
> newly installed consumer unit at the inverter position.
>
> Install 1 x 32A rotary isolator at the mains intake position & 1 x
> generation meter.
>
> Connect all cabling to the inverter and battery storage.
>
> Commission, test, inspect & handover to client.
>
> Subtotal £11,947.81
> Total £11,947.81
>
> Scaffolding has been allowed for in this quotation for the duration of
> the works.
> Once the work has been completed, an electrical installation
> certificate, part p certificate & MCS certificate will be issued1 / 2l
>
> Any comments from cognoscenti would be welcomed.
>

--
Spike

RustyHinge wrote:

> Install 10mm 3 core SWA from the existing house consumer unit up to the
> newly installed consumer unit at the inverter position.

10mm^2 SWA seems excessive, even if the cable run is 16 metres, 2.5mm^2
T&E would be suitable for the 21A required by a 5kW inverter.

On 01/07/2023 10:39, Andy Burns wrote:
> RustyHinge wrote:
>
>> Install 10mm 3 core SWA from the existing house consumer unit up to
>> the newly installed consumer unit at the inverter position.
>
> 10mm^2 SWA seems excessive, even if the cable run is 16 metres, 2.5mm^2
> T&E would be suitable for the 21A required by a 5kW inverter.
>
Better overkill than later problems with overheating in the event of
additions to circuit later?

At least no-one's come up with X is rubbish quality or similar.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On Sat, 1 Jul 2023 10:39:17 +0100, Andy Burns <usenet@andyburns.uk>
wrote:

>RustyHinge wrote:
>
>> Install 10mm 3 core SWA from the existing house consumer unit up to the
>> newly installed consumer unit at the inverter position.
>
>10mm^2 SWA seems excessive, even if the cable run is 16 metres, 2.5mm^2
>T&E would be suitable for the 21A required by a 5kW inverter.

It does say from current CU to a new CU: maybe it has functions other
than connecting the inverter (though I can't imagine what)? Also,
maybe 7671 says it has to be 10mm?

Can't see the point in SWA though, unless it runs up the outside of
the house.

--

-Pip

On 01/07/2023 14:13, Pipl wrote:
> On Sat, 1 Jul 2023 10:39:17 +0100, Andy Burns <usenet@andyburns.uk>
> wrote:
>
>> RustyHinge wrote:
>>
>>> Install 10mm 3 core SWA from the existing house consumer unit up to the
>>> newly installed consumer unit at the inverter position.
>>
>> 10mm^2 SWA seems excessive, even if the cable run is 16 metres, 2.5mm^2
>> T&E would be suitable for the 21A required by a 5kW inverter.
>
> It does say from current CU to a new CU: maybe it has functions other
> than connecting the inverter (though I can't imagine what)? Also,
> maybe 7671 says it has to be 10mm?
>
> Can't see the point in SWA though, unless it runs up the outside of
> the house.

It's the most direct route, and much simpler. Added to that, it can
enter right beside the meter/fuse &c.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On 01/07/2023 14:13, Pipl wrote:
> On Sat, 1 Jul 2023 10:39:17 +0100, Andy Burns <usenet@andyburns.uk>
> wrote:
>> RustyHinge wrote:
>>
>>> Install 10mm 3 core SWA from the existing house consumer unit up to
>>> the newly installed consumer unit at the inverter position.
>>
>> 10mm^2 SWA seems excessive, even if the cable run is 16 metres,
>> 2.5mm^2T&E would be suitable for the 21A required by a 5kW inverter.
>
> It does say from current CU to a new CU: maybe it has functions
> other than connecting the inverter (though I can't imagine what)
> Also,maybe 7671 says it has to be 10mm?

There could be a bonding issue. The steel armouring is sufficient to act
as the circuit protective conductor (earth cable) for the circuit, but,
if the PVs need bonding (possible if they are metal, and likely to bring
in an earth potential), then it will need a 10mm (copper) cable to
comply. The SWA armour is, without looking in my books, equivalent to
around 4mm copper, and not large enough to act as a bonding conductor,
which needs to be 10mm copper or equivalent.
The 'running hot' scenario is possible, 2.5mm T+E has a current carrying
capacity of around 26 amps in free air. That means if it is constantly
running at 26 amps, it will be near to its operating limit of 70
degrees. (though in real life, i doubt it would get above 50 deg.)
Making the conductors larger eliminates the losses through less heating
of the cable (less resistance in the cable) so is a good thing, though
I'd say 6mm should be sufficient for the live conductors, but, as above,
if bonding is an issue, 10mm will be used, and the cable will run even
cooler, and lose less energy.

> Can't see the point in SWA though, unless it runs up the outside of
> the house.

T+E cable isnt UV protected, the outer sheath will get brittle over
time, so it needs enclosing in conduit or similar. SWA is easier to fit,
and tougher as well.

--
Remove the '+' and replace with 'plus' to reply by email

On 02/07/2023 19:58, Alan Lee wrote:

> There could be a bonding issue. The steel armouring is sufficient to act
> as the circuit protective conductor (earth cable) for the circuit, but,
> if the PVs need bonding (possible if they are metal, and likely to bring
> in an earth potential), then it will need a 10mm (copper) cable to
> comply. The SWA armour is, without looking in my books, equivalent to
> around 4mm copper, and not large enough to act as a bonding conductor,
> which needs to be 10mm copper or equivalent.
> The 'running hot' scenario is possible, 2.5mm T+E has a current carrying
> capacity of around 26 amps in free air. That means if it is constantly
> running at 26 amps, it will be near to its operating limit of 70
> degrees. (though in real life, i doubt it would get above 50 deg.)
> Making the conductors larger eliminates the losses through less heating
> of the cable (less resistance in the cable) so is a good thing, though
> I'd say 6mm should be sufficient for the live conductors, but, as above,
> if bonding is an issue, 10mm will be used, and the cable will run even
> cooler, and lose less energy.

/snippage/

I assume they will/may run the pv output on the west elevation, which
gets warm in the sun in the evening. BICBW

I'm all for overkill if the load is approaching the limit.

Talking of limits, is there one for charging batteries during cheaper
periods and selling the excess back to supplier 'at best'?

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On 01/07/2023 03:04, RustyHinge wrote:

>
> Any comments from cognoscenti would be welcomed.
>

On 03/07/2023 12:26, ajh wrote:
> On 01/07/2023 03:04, RustyHinge wrote:
>> Supply & install 10 x Tigo Optimisers to the panels to improve
>> performance due to shading.
>
>
> I know nothing about optimisers but the spec looks good and I like the
> Givenergy inverter. It can be wired "islanded" to keep going in a power
> cut.
>
> Given the strings are on different orientations you are unlikely to ever
> see your peak installed power.
>
> I would try and see if any more capacity of panels could be fitted as I
> think you would do better fitting a few more panels.
>
> My daughter's system cost £12k in April but has 6kW of panels in two
> strings and a zappi car charger in that cost.
Eh up looks like thunderbird messed up my filesystem, did this get posted?

On 04/07/2023 11:09, ajh wrote:

> Eh up looks like thunderbird messed up my filesystem, did this get posted?

I certainly didn't see it, but strange things have been going on in the
swerver - 15 posts, it saysin the usual place: open one and that figure
dwindles to one, or zero unread.

Thanks: my first impression was that they've crammed as many panels on
as they can , and to get any more output might entail waiting for New!
Improved! Super Double Density! panels to be invented.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On Tuesday, 4 July 2023 at 12:23:19 UTC+1, RustyHinge wrote:
> On 04/07/2023 11:09, ajh wrote:
>
> > Eh up looks like thunderbird messed up my filesystem, did this get posted?
> I certainly didn't see it, but strange things have been going on in the
> swerver - 15 posts, it saysin the usual place: open one and that figure
> dwindles to one, or zero unread.
>
> Thanks: my first impression was that they've crammed as many panels on
> as they can , and to get any more output might entail waiting for New!
> Improved! Super Double Density! panels to be invented.

My learning is that once you've opened your wallet the cost of an extra
panel or two (400 quid or so?) is probably worth it. At peak times you'll
probably be exporting anyway but during short days and overcast days
anything that pumps up the production is probably desirable.

On 04/07/2023 12:56, Stephen Packer wrote:

> My learning is that once you've opened your wallet the cost of an extra
> panel or two (400 quid or so?) is probably worth it. At peak times you'll
> probably be exporting anyway but during short days and overcast days
> anything that pumps up the production is probably desirable.

My thinking exactly, but I think they may have crammed-in as many as
they can already: but we shall see.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.