Solar panels and battery - any real world reccomendations?

DampCat · 21 Aug 2023 at 12:27

McBain said:
Anyone used Eon for a solar install?

Yes both my neighbour and I.

My install was easy. I had to email them a couple of times for updates after they'd given a timeframe and then not heard anything but absolutely nothing compared to dealing with British Gas or similar.

I guess it's the subcontractors who make or break the experience. Mine were great.

Mercenary Keyboard Warrior · 21 Aug 2023 at 12:32

Siliconslave said:
You know if you switch to the local mode on the app and flip to the data dat in grid you get the total consumed grid power (for the life of the inverter) at the point of refresh. The data then is live and not limited by the 5 min delay rubbish You can query that via rest as well but the decoding is a bit of a pain!

I think I get that.

The issue is really getting proof of everything.

Solax keep saying all is fine when even the installer now says its not.
I was going on input since its a decent proxy for output when its full charges from 10% soc to 100% soc. But as I keep saying to them this is pre losses so its worse (quoted 97% charge / discharge efficiency)

McBain · 21 Aug 2023 at 12:49

200sols said:
They just subcontract out the work and all the pitfalls that entails.

DampCat said:
Yes both my neighbour and I.

My install was easy. I had to email them a couple of times for updates after they'd given a timeframe and then not heard anything but absolutely nothing compared to dealing with British Gas or similar.

I guess it's the subcontractors who make or break the experience. Mine were great.

Thanks both, good info.

94JDH · 21 Aug 2023 at 15:39

SBo said:
Haha yes!
So I wrote to Tigo and asked them to disable the automatic power cut-off function in the end, which they did do remotely - if you don't do that then anytime your Tigo TAP and CCA lose power the optimisers will cut the power. I gather that some countries require it for safety but the UK doesn't and I would want to use solar as backup in an outage. I have a switch connected to the CCA which if you push it "emergency shut down" happens and the optimisers cut power. Useful for safer servicing in the future.

I had to muck around for a while with TAP placement, trial and error and I didn't really want to buy any more TAPs, in the end it could rach all the panels from inside my loft roughly in the middle of my array (which is split across 3 roofs)

I've read about it online causing issues- what I find strange is a second string with 8 panels attached all with repurposed Tigo's is knocking out 280v fine ( this is also not connected to the inverter yet) - I wonder why this hasn't resulted in a rapid shutdown?

SBo · 21 Aug 2023 at 15:44

94JDH said:
I've read about it online causing issues- what I find strange is a second string with 8 panels attached all with repurposed Tigo's is knocking out 280v fine ( this is also not connected to the inverter yet) - I wonder why this hasn't resulted in a rapid shutdown?

So if the Tigo has never been paired with a CCA then auto shut-down on power-loss is not active. (Or otherwise blind deployments wouldn't be possible).
So presumably the Tigos on your dead string have been paired through the web portal/app already?
The repurposed ones presumably were removed from another site so un-paired or at that site the installer/user did what I did and had Tigo de-activate the auto shut-down on CCA loss.

Hawk Tuah · 21 Aug 2023 at 15:44

Older firmware, no internet connectivity to be updated?

94JDH · 21 Aug 2023 at 16:27

SBo said:
So if the Tigo has never been paired with a CCA then auto shut-down on power-loss is not active. (Or otherwise blind deployments wouldn't be possible).
So presumably the Tigos on your dead string have been paired through the web portal/app already?
The repurposed ones presumably were removed from another site so un-paired or at that site the installer/user did what I did and had Tigo de-activate the auto shut-down on CCA loss.

Long story, but keep it short!
These were used on my old system but because of other issues, all the DC side was replaced including panels and Tigo's.
As I already had a Tigo account but was managed by the previous installer ( gone bust) it has taken a while to gain the proper access to the account.
All new Tigo's on new panels I have set up correctly via the spreadsheet upload on the portal - I'm now repurposing the old ones, but as they are not currently connected to the inverter I'm guessing this is half the problem.

Mercenary Keyboard Warrior · 21 Aug 2023 at 17:09

Ok so my new batteries dont look good. Showing very similar issues to the last ones. These even had the special 48 hour balancing mode switched on.

So the plan is :
Tonight dump battery to (min SOC) 10%. (Manually around 11ish or so, depends when I want to go to bed)
Set charge time 0:30 - 3:00am.
Allow discharge from 3am onwards.
Isolate PV tonight once sun is down. So no power from PV tomorrow until batteries dead.

So tomorrow I do a full charge from 10-100% and then 100-10% in effect, all in one day with decent but not silly hot weather.
When at 10% as PV is off the yield will be a full battery dump, and that only.

This will show in one day the full charge and discharge of the batteries. The yield being the released energy to the house.

Running a sweepstake on battery to house. Listed at 12.3kwh (100% SOC) and 11kwh usable (90% SOC).
I am going with 9.5kwh.

b0rn2sk8 · 21 Aug 2023 at 17:27

9.49

reef · 21 Aug 2023 at 18:11

Mercenary Keyboard Warrior said:
Ok so my new batteries dont look good. Showing very similar issues to the last ones. These even had the special 48 hour balancing mode switched on.

So the plan is :
Tonight dump battery to (min SOC) 10%. (Manually around 11ish or so, depends when I want to go to bed)
Set charge time 0:30 - 3:00am.
Allow discharge from 3am onwards.
Isolate PV tonight once sun is down. So no power from PV tomorrow until batteries dead.

So tomorrow I do a full charge from 10-100% and then 100-10% in effect, all in one day with decent but not silly hot weather.
When at 10% as PV is off the yield will be a full battery dump, and that only.

This will show in one day the full charge and discharge of the batteries. The yield being the released energy to the house.

Running a sweepstake on battery to house. Listed at 12.3kwh (100% SOC) and 11kwh usable (90% SOC).
I am going with 9.5kwh.

I found with my Fox batteries they took a good couple of months to balance properly. I'm running 12.25kWh of them in total and was frustrated with only around 9kWh of capacity at first (even worse when cold). Over time this has come up though with around 95-97% of what should be usable now being accessable. My min SOC is 10% so I get 11.0kWh usable. On a full charge I get around 95-97% of that so with losses its about right (10.6kWh or so).

I think a lot of it is down to firmware as with these chinese-made Inverters, BMS and batteries the software side is garbage.

Mercenary Keyboard Warrior · 21 Aug 2023 at 18:15

reef said:
I found with my Fox batteries they took a good couple of months to balance properly. I'm running 12.25kWh of them in total and was frustrated with only around 9kWh of capacity at first (even worse when cold). Over time this has come up though with around 95-97% of what should be usable now being accessable. My min SOC is 10% so I get 11.0kWh usable. On a full charge I get around 95-97% of that so with losses its about right (10.6kWh or so).

I think a lot of it is down to firmware as with these chinese-made Inverters, BMS and batteries the software side is garbage.

I gave the first set from end of Nov 22 until last week, they never changed basically.
Also, mine ran a special balancing thing for 48 hours over the weekend, also seems to have made no diff.

We also checked the SOC of the batteries before we installed, but also the balancing thing is supposed to fix this.
If they were out in advance I can see how they could take a long time to balance. But if they are borked they are never going to get there.

KompuKare · 21 Aug 2023 at 18:57

Mercenary Keyboard Warrior said:
Ok so my new batteries dont look good. Showing very similar issues to the last ones. These even had the special 48 hour balancing mode switched on.

So the plan is :
Tonight dump battery to (min SOC) 10%. (Manually around 11ish or so, depends when I want to go to bed)
Set charge time 0:30 - 3:00am.
Allow discharge from 3am onwards.
Isolate PV tonight once sun is down. So no power from PV tomorrow until batteries dead.

So tomorrow I do a full charge from 10-100% and then 100-10% in effect, all in one day with decent but not silly hot weather.
When at 10% as PV is off the yield will be a full battery dump, and that only.

This will show in one day the full charge and discharge of the batteries. The yield being the released energy to the house.

Running a sweepstake on battery to house. Listed at 12.3kwh (100% SOC) and 11kwh usable (90% SOC).
I am going with 9.5kwh.

But can your battery dump at the full max discharge until 10%? Mine when "dumping" by using the immersion certainly tapers off - in the case of immersion this means buying from the grid so immersion dumps are pretty inefficient.

Point being, if during the PV off time you use more than x Watts it may buy from the grid.

Had a quick look at Octopus's Consumption_kWh versus my inverter's Daily Energy Purchased(kWh) and it was pretty close with 6.1 kWh of Octopus being around 5.9 kWh as measured by the inverter.

For balancing, have you got access to console to the batteries? Mine don't show much but I get like this:

Pack	Battery Volt Curr Tempr Base State Volt. State Curr. State Temp. State Coulomb
1	0 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	1 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	2 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	3 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	4 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	5 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	6 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	7 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	8 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	9 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	10 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	11 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	12 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	13 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	14 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1	15 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
	Battery Volt Curr Tempr Base State Volt. State Curr. State Temp. State Coulomb
2	0 3313 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	1 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	2 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	3 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	4 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	5 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	6 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	7 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	8 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	9 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	10 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	11 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	12 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	13 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	14 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2	15 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH

So at least their BMS thinks everything is fine

Mercenary Keyboard Warrior · 21 Aug 2023 at 19:51

KompuKare said:
But can your battery dump at the full max discharge until 10%? Mine when "dumping" by using the immersion certainly tapers off - in the case of immersion this means buying from the grid so immersion dumps are pretty inefficient.

Point being, if during the PV off time you use more than x Watts it may buy from the grid.

Had a quick look at Octopus's Consumption_kWh versus my inverter's Daily Energy Purchased(kWh) and it was pretty close with 6.1 kWh of Octopus being around 5.9 kWh as measured by the inverter.

For balancing, have you got access to console to the batteries? Mine don't show much but I get like this:

Pack Battery Volt Curr Tempr Base State Volt. State Curr. State Temp. State Coulomb
1
0 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
1 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
2 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
3 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
4 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
5 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
6 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
7 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
8 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
9 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
10 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
11 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
12 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
13 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
14 3314 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
1
15 3315 -3216 19000 Dischg Normal Normal Normal 96% 96351 mAH
Battery Volt Curr Tempr Base State Volt. State Curr. State Temp. State Coulomb
2
0 3313 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
1 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
2 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
3 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
4 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
5 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
6 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
7 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
8 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
9 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
10 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
11 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
12 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
13 3315 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
14 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH
2
15 3314 -2600 19000 Dischg Normal Normal Normal 98% 98258 mAH

So at least their BMS thinks everything is fine

If I switch my system to manual, at that point if I select discharge it dumps at 5.5kw until its down to 10% Soc
Mine doesn't have any logs like that

Welshman · 21 Aug 2023 at 20:01

Mercenary Keyboard Warrior said:
If I switch my system to manual, at that point if I select discharge it dumps at 5.5kw until its down to 10% Soc
Mine doesn't have any logs like that

I know you said you was thinking of adding more panels… city plumbing now have 370w panels for £87.

Mercenary Keyboard Warrior · 21 Aug 2023 at 20:05

Welshman said:
I know you said you was thinking of adding more panels… city plumbing now have 370w panels for £87.

Been looking into my system and due to the whole house EPS I cannot.
I would have to drop the advanced matebox (which does the EPS) and then I could run two inverters.

I thought I could maybe add all my panels to one string but its limited to 14A per string and I was pulling 22A and above this afternoon across the two strings.

I am going to ditch the idea for now.

Solax in regards inverters are well regarded so there is some hope they work out a way round the EPS thing being one inverter only.

SBo · 21 Aug 2023 at 22:16

Mercenary Keyboard Warrior said:
Been looking into my system and due to the whole house EPS I cannot.
I would have to drop the advanced matebox (which does the EPS) and then I could run two inverters.

I thought I could maybe add all my panels to one string but its limited to 14A per string and I was pulling 22A and above this afternoon across the two strings.

I am going to ditch the idea for now.

Solax in regards inverters are well regarded so there is some hope they work out a way round the EPS thing being one inverter only.

I’m not clear why there is a problem, if the new inverter is installed upstream (ie grid side) of the current one.
In a daytime powercut; both inverters may not recognise the loss of grid due to them both supplying (same as your neighbours’ inverters to your house!) but very quickly there will be a demand/supply inbalance, both inverters will see the frequency move out of range and shut down supply; EPS will kick in on the old inverter and supply as required. They will then stay offline until grid power is restored.

Mercenary Keyboard Warrior · 21 Aug 2023 at 22:45

SBo said:
I’m not clear why there is a problem, if the new inverter is installed upstream (ie grid side) of the current one.
In a daytime powercut; both inverters may not recognise the loss of grid due to them both supplying (same as your neighbours’ inverters to your house!) but very quickly there will be a demand/supply inbalance, both inverters will see the frequency move out of range and shut down supply; EPS will kick in on the old inverter and supply as required. They will then stay offline until grid power is restored.

Hmm interesting thoughts thanks.

I went from a video from the manufacturer that had a summary table. This listed X1 (single phase) G4 (4th gen) with matebox EPS as not being allowed to be parallel.

But what you just described is serial. So maybe they could work in serial.

I assume by in parallel they mean in effect they sit at the same point between grid and CU.
(mine has a different link to the CU compared to most installs, the tails divert from the meter to the matebox and then back to the meter cabinet and to the CU)

So the second inverter would need to tap into those tails.

To be fair the sparkie who has visited not 4-5 times (I lost count) didnt seem to think there would be an issue adding another inverter so maybe the training video I picked up on was misleading.

This was the vid, at 6min 49 if the timestamp doesnt work

chris1012 · 21 Aug 2023 at 23:12

I am early onto my PV journey and after some initial research I have got in touch with some MCS approved installers that will install in North East London.

Each of the installers have come back with a different design ranging from 12 panels to 20 panels! 18 would be ideal!

I have attached the diagram that looks to me most likely achievable however I still have reservations on the design due to the blue highlighted ridge line (around 20cm tall) which could/will cause shading? None of the installers have called out shading as of yet...

The 1st dormer flat roof is on a higher level to the 2nd rear dormer flat roof as well, please see attached photo's.
What is the maximum amount of panels I can install?
Is there any way of getting an accurate survey done?

Roof estimated sizes are -
Roof 1 - 490cm by 270cm (velux windows are 60cm by 60cm)
Roof 2 - 495cm by 320cm
Roof 3 - 285cm by 260cm
Roof 4 - 360cm by 300cm (Velux window 150cm by 130cm)

What would be a realistic price for the following? -

6000kW annual usage (12-15kW daily)

16 - 18 panels 415Wminimum, although happy to pay for more powerful panels if they still fit on the roofs.
6kw+ Inverter
10kWh+ Battery
Solar Optimisers (for shading?)

G99 - If we go for the above setup, my basic understanding is that we would need a G99 DNO application submitted?
Should we get this done prior to finding an installer in case the application was rejected?
What would happen if we had the setup installed and the G99 application was rejected?
*UK Power Networks is our provider, not national grid

Hot Water Cylinder - We have 250L indirect cylinder in the house that is setup to run in the early hours on the morning for 2hrs each day to heat up the water (predominantly using the boiler/Gas to heat up).
Should we put the cylinder on fully electric? I understand it would take a much longer time to heat up.

Are there any other considerations to make and any recommendations on reputable installers for London?
There seems to be plenty of MCS installers around at the moment so would be good to know what to look out for, as I have heard and read a number of horror install stories!

If the costs were too high, for the ideal setup, would it be advisable to install the panels and inverter now with wiring setup for future purchase of a battery?

SBo · 22 Aug 2023 at 08:38

Mercenary Keyboard Warrior said:
Hmm interesting thoughts thanks.

I went from a video from the manufacturer that had a summary table. This listed X1 (single phase) G4 (4th gen) with matebox EPS as not being allowed to be parallel.

But what you just described is serial. So maybe they could work in serial.

I assume by in parallel they mean in effect they sit at the same point between grid and CU.
(mine has a different link to the CU compared to most installs, the tails divert from the meter to the matebox and then back to the meter cabinet and to the CU)

So the second inverter would need to tap into those tails.

To be fair the sparkie who has visited not 4-5 times (I lost count) didnt seem to think there would be an issue adding another inverter so maybe the training video I picked up on was misleading.

This was the vid, at 6min 49 if the timestamp doesnt work

Parallel to them means alongside one another connected to the same matebox terminals. What I'm describing is independent of the SolaX hardware.
So there must be a switch fuse or small CU between your meter and the tails into the matebox. Your sparky would either put an MCB in there for your second inverter or use henley blocks to split the tails and add a standalone consumer unit for it, with its CT clamp on the main tail next to the meter. I wouldn't complicate things by adding battery storage on the new inverter as they may compete to discharge to meet demand creating issues.
The only other item I can think to consider is managing the export limit if required by your G99/100. I think the investers will allow you to set a max export as measured by the CT clamps at (say) 3.68kw so that would be cumulative and therefore fine, but I would just check that detail.

Mercenary Keyboard Warrior · 22 Aug 2023 at 09:18

SBo said:
Parallel to them means alongside one another connected to the same matebox terminals. What I'm describing is independent of the SolaX hardware.
So there must be a switch fuse or small CU between your meter and the tails into the matebox. Your sparky would either put an MCB in there for your second inverter or use henley blocks to split the tails and add a standalone consumer unit for it, with its CT clamp on the main tail next to the meter. I wouldn't complicate things by adding battery storage on the new inverter as they may compete to discharge to meet demand creating issues.
The only other item I can think to consider is managing the export limit if required by your G99/100. I think the investers will allow you to set a max export as measured by the CT clamps at (say) 3.68kw so that would be cumulative and therefore fine, but I would just check that detail.

Unless hes hidden something in the short piece of trunking (I doubt there is room tbh) that goes from the meter to the matebox its like this

--> incoming --> DN0 fuse (for want of a better description) --> Meter box --> Tails to matebox --> tails to some kind of trip/fuse/switch* --> tails to CU
So the change was to switch the tails out of the meter from going to the CU, instead it goes through about 1m max of trunking, into and back out of the mate box then to this trip/fuse/switch thing

I think BG added that when they replaced the meter with the smart one, if not the solar installer added it when they made the changes to the setup to add the matebox into the equation.

The trip/fuse/switch thing, is a Wylex WS102TT.