Solar Panels?

[g40steve]

Evanivitch said:

The adverts? Why don't you read the dozen or so studies that consider the whole lifecycle analysis and environmental impact of electric cars versus ICE, and all come out in favour of EV...

And yes, loads of people have measured the eco cost of solar. And yes, when compared to current UK energy mix solar panels do reduce environmental impact. Batteries don't generate electricity, but they do maximise use of renewable energy and minimise the use of diesel/OCGT STOR powerstations that typically meet our evening demand.

Arrgh, the studies by the car manufacturers themselves?
Your EV is basically + 50% the price of ICE comparable models.
It has less moving parts yet serving quotes are higher for EV?
@ what point will the EV need a new battery & currently hardly anything in it running costs.
Yes if you have an EV as company car BIC makes them worthwhile but the majority or users not viable.
The production of the batteries are no way green, the chemicals, elements involved & cannot see these being economical to recycle after the vehicle is scrapped.

[dmsims]

All I can be bothered to say is custard

Your starter for 10: compare an ID3 to a Golf

g40steve said:

Arrgh, the studies by the car manufacturers themselves?
Your EV is basically + 50% the price of ICE comparable models.
It has less moving parts yet serving quotes are higher for EV?
@ what point will the EV need a new battery & currently hardly anything in it running costs.
Yes if you have an EV as company car BIC makes them worthwhile but the majority or users not viable.
The production of the batteries are no way green, the chemicals, elements involved & cannot see these being economical to recycle after the vehicle is scrapped.

[g40steve]

You were saying, this is before energy prices went crazy?

https://www.carbuyer.co.uk/family-hatchbacks/30427...

[AW10]

Previous said:

Second quote has come in:

10x 395w Ja panels
9.5 givenergy battery
Solis 3.6kw mppt (I've no idea what this is)
Givenergy 3.0kw coupled charge inverter
All installed, scaffolding etc

£12,300 installed

Previous quote was £11,300 with a 6.5kw growatt battery instead.

No idea if either are any good price wise... what do the resident PH experts think?

We're quite frugal users - circa 2,800kw per year for a family of 3 in a 4 bed detached (South west). Roof is south facing, circa 20 degrees off towards the south west).No EV (but maybe one day).

Edited by Previous on Saturday 1st October 09:25

Bear in mind your annual leccy bill is 2800 * 0.34 = £952 per year. IMHO bestest best case you’ll reduce your grid import by 2/3s. So panels and battery will save you ~£655/year. At £11.3K for a system that’s a 17 year payback.

Edited by AW10 on Saturday 1st October 15:03

[AW10]

Previous said:

On the payback, the lower quote indicated £1400 saving per year, based upon the panels plus battery and the SEG. That'd give a payback of 8 years

Just saw this.

How on earth did they get to £1400 of savings when your annual consumption is less than £1000?!?!

To add some maths to my claim…

A 3.95 kWp system will probably generate an average of 4200 kWH/year.

In the unlikely event you were able to utilise 100% of that energy in house you would save £952 and be paid £70 for the SEG (at 5p/kWh).
If you used 2/3s you would save £635 and be paid £117.

Neither sum is remotely close to £1400.

Edited by AW10 on Saturday 1st October 15:59

[eldar]

Previous said:

Second quote has come in:

10x 395w Ja panels
9.5 givenergy battery
Solis 3.6kw mppt (I've no idea what this is)
Givenergy 3.0kw coupled charge inverter
All installed, scaffolding etc

£12,300 installed

Previous quote was £11,300 with a 6.5kw growatt battery instead.

No idea if either are any good price wise... what do the resident PH experts think?

We're quite frugal users - circa 2,800kw per year for a family of 3 in a 4 bed detached (South west). Roof is south facing, circa 20 degrees off towards the south west).No EV (but maybe one day).

Edited by Previous on Saturday 1st October 09:25

I'vejust had a quote for 20 x 400w panels, 8KW inverter, 5.2 kw battery and all in fitting, 13,100. Roof is E& W so 2 banks of 10. We use around 3,500 kwh currently, but an electric car is in plan.

[Evanivitch]

g40steve said:

Arrgh, the studies by the car manufacturers themselves?

Nope.

g40steve said:

Your EV is basically + 50% the price of ICE comparable models.

Nope.

g40steve said:

It has less moving parts yet serving quotes are higher for EV?

Nope.

g40steve said:

@ what point will the EV need a new battery & currently hardly anything in it running costs.

Same time an ICE needs a new engine, when it breaks.

BTW, 7.5p/kWh...

g40steve said:

Yes if you have an EV as company car BIC makes them worthwhile but the majority or users not viable.

Nope.

g40steve said:

The production of the batteries are no way green, the chemicals, elements involved & cannot see these being economical to recycle after the vehicle is scrapped.

Of course manufacturing an ICE and extracting and refining oil is greener?

Nope.

There's at least a dozen threads on this already on PH, about a hundred sources you could check with a quick Google, but willful ignorance just isn't worth the effort. I might as well report you for posting false information.

[505diff]

A week into our 10 panels and 5.2 KWh battery going live, in weather that produced a couple of sunny days, a few cloudy dull intermittent sun days and a rainy misty day, we have covered all our power requirements (4 bed house with two young children so washing machine on overtime) exported 5 KWh, and heated about 90% of hot water requirement including the 12 baths taken by the family over a week for approximately an 8k investment.

Saved on gas a bit and saved on electricity a lot, no doubt the next few months will yield less, but so far I’m impressed, a lot.

[NMNeil]

g40steve said:

The production of the batteries are no way green, the chemicals, elements involved & cannot see these being economical to recycle after the vehicle is scrapped.

Recycling car batteries.
https://www.youtube.com/watch?v=Qi8Y2lF7Luw
vs. recycling car batteries.
https://www.youtube.com/watch?v=aH_HKeS1Ed4
Which is cleaner?

[Pistonsquirter]

dmsims said:

Pistonsquirter said:

MPPT is the type of battery charger.

It's a type of Solar charge controller, what happens if there are no batteries ? (don't answer that)

That’s pretty much what I said but with more opaqueness.
From experience of initially using a non-MPPT charger on our electric fence array, the car battery became borkerized quick. It’s about battery peak charge detection, this is not PV specific, eg battery ‘conditioners’ / intelligent trickle chargers have this feature. I did buy a dirt cheap China special tbf.

Sorry for hijack OP, perhaps to contribute, a colleague has a PV array and a battery bank, he has an immersion in his tank which is ‘primarily fed’ (he says) from the battery inverter and is on a timer switch for 1 or 2 hrs a day, and he can use this for all hot water. Basically all his HW is provided by his PV, so he uses no gas for it now. Winter with CH is tbc though lol

[Previous]

505diff said:

A week into our 10 panels and 5.2 KWh battery going live, in weather that produced a couple of sunny days, a few cloudy dull intermittent sun days and a rainy misty day, we have covered all our power requirements (4 bed house with two young children so washing machine on overtime) exported 5 KWh, and heated about 90% of hot water requirement including the 12 baths taken by the family over a week for approximately an 8k investment.

Saved on gas a bit and saved on electricity a lot, no doubt the next few months will yield less, but so far I’m impressed, a lot.

Which part of the country are you based in? £8k for your system sounds pretty reasonable.

[OutInTheShed]

Pistonsquirter said:

....
From experience of initially using a non-MPPT charger on our electric fence array, the car battery became borkerized quick. It’s about battery peak charge detection, this is not PV specific, eg battery ‘conditioners’ / intelligent trickle chargers have this feature. I did buy a dirt cheap China special tbf.
....l

That is not a lack of MPPT functionality, it's a matter of the charger not turning down to a maintenance or float level once the battery is charged.

Death by overcharging can happen with any lead acid battery if the controller is rubbish or set wrong.
Or simply designed for another purpose!

You can get away with no controller at all if the panel is small compared to the battery, e.g. a 5W panel float charging a 100Ah battery on a boat.
We're OT now!

[505diff]

Previous said:

505diff said:

A week into our 10 panels and 5.2 KWh battery going live, in weather that produced a couple of sunny days, a few cloudy dull intermittent sun days and a rainy misty day, we have covered all our power requirements (4 bed house with two young children so washing machine on overtime) exported 5 KWh, and heated about 90% of hot water requirement including the 12 baths taken by the family over a week for approximately an 8k investment.

Saved on gas a bit and saved on electricity a lot, no doubt the next few months will yield less, but so far I’m impressed, a lot.

Which part of the country are you based in? £8k for your system sounds pretty reasonable.

Near Cambridge, system was £7,700 give or take a pound or two, via the Solar together auction, then I’ve fitted an Eddi for the immersion heater so around 8k. Costs may have increased like anything else but to be honest £8700 just for the solar and battery would still get me signing up.

[Enut]

Have any of you self employed PHers who worked from home claimed any of the expense of fitting Solar as a business expense?

My system is nearly complete (just waiting a technician to replaced an apparently faulty battery), I included a 12Kw battery and EPS system to provide a backup for the home office in the event of power cuts so was thinking I could claim some or all of that cost as well as percentage of the overall cost?

Any opinions or accountants comments welcome.

[AW10]

IANAA but unless an expense is wholly and exclusively for business use it can't be claimed. You can bend the rules on IT equipment because it's hard to prove that it isn't solely for the business but solar PV is all too easy to prove it isn't solely for business use.

[TriumphStag3.0V8]

dmsims said:

If you look at the demand there is no excess generation

Nothing to see here......

TriumphStag3.0V8 said:

Not trying to be a dick here, but it shouldn't. The point of the battery is it sits there collecting excess generation for your later use, rather than letting it go out to the grid (effectively wasted) and should be topping up your use over and above what the panels are providing only.

It's pointless having a battery if it just discharges to the grid. Something is definately wrong there.

You should only be exporting to the grid if the panels are producing more than you are using and the battery is full.

Edited by TriumphStag3.0V8 on Saturday 1st October 10:08

In which case your battery should just be topping up generation to meet demand, not exporting out to the grid.
I'm not trying to be funny, just genuinely trying to understand what is going on. Unless there is an inbound parrot.

[OutInTheShed]

TriumphStag3.0V8 said:

In which case your battery should just be topping up generation to meet demand, not exporting out to the grid.
I'm not trying to be funny, just genuinely trying to understand what is going on. Unless there is an inbound parrot.

That's an 800W system.
The image contains 'Victron' logos.

That suggests to me a system as might be found on a boat.

It could be a snapshot of the system changing over or something, possibly the mains has only just been connected, so the inverter is ramping down.
Possibly the mains voltage is low.
Possibly the AC load has just been reduced and the inverter is over-reacting.

I've seen some odd things happen with these systems.
It is possible to make them do things which are not what you'd first think of, like discharge the batteries for a test, or to set lithium batteries to a preferred state of charge for long term storage.
I don't think one should read very much into a single screenshot without a lot of context.

But IMHO, certain hardware providers change their firmware more often than their underwear and some installers have some funny ideas about setting things up. Some boat owners have an interesting mixture of 'stuff' and compatibility issues.
I would not be at all surprised to find the 'grid' actually means 'stuff beyond this subsystem but still on the boat'.
It may not be on a boat of course, it could be any installation.
There is a lot of PV in the world doing other things than your average domestic installation.
Maybe the owner will illuminate, if not there are plenty of off-beat victron users on the interweb.

[TriumphStag3.0V8]

OutInTheShed said:

TriumphStag3.0V8 said:

In which case your battery should just be topping up generation to meet demand, not exporting out to the grid.
I'm not trying to be funny, just genuinely trying to understand what is going on. Unless there is an inbound parrot.

That's an 800W system.
The image contains 'Victron' logos.

That suggests to me a system as might be found on a boat.

It could be a snapshot of the system changing over or something, possibly the mains has only just been connected, so the inverter is ramping down.
Possibly the mains voltage is low.
Possibly the AC load has just been reduced and the inverter is over-reacting.

I've seen some odd things happen with these systems.
It is possible to make them do things which are not what you'd first think of, like discharge the batteries for a test, or to set lithium batteries to a preferred state of charge for long term storage.
I don't think one should read very much into a single screenshot without a lot of context.

But IMHO, certain hardware providers change their firmware more often than their underwear and some installers have some funny ideas about setting things up. Some boat owners have an interesting mixture of 'stuff' and compatibility issues.
I would not be at all surprised to find the 'grid' actually means 'stuff beyond this subsystem but still on the boat'.
It may not be on a boat of course, it could be any installation.
There is a lot of PV in the world doing other things than your average domestic installation.
Maybe the owner will illuminate, if not there are plenty of off-beat victron users on the interweb.

Gotcha, thanks.

It was just that he said "that's what normally happens" regarding exporting to the grid - threw me a bit.

[dmsims]

OK - the inverter is a Victron Multiplus - in a shed!

There are 2 AC outputs - one for AC loads - this powers all the pond stuff directly

The other is connected to the house (grid)

In Victron's ESS you can set set the amount you want to send to the grid:



The batteries take up the slack when insufficient PV and are charged when excess PV

They are also a on ascheduled charge from 2030 to 0130 (Octopus Go faster)

[OutInTheShed]

dmsims said:

OK - the inverter is a Victron Multiplus - in a shed!

T.......

Always interesting to see different systems.
Thanks for posting more info.