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23.000€ New install, generator kicks in most nights. Normal?

Jorgeb

New Member
Joined
Nov 24, 2021
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11
Hey All,

As you will see, I’m new to this form and completely new to solar in general. I introduced myself, so excuse the repeat if you read the first post.
Firstry, id like to thank everyone who takes time to even read my posts, and to also ask for forgiveness upfront for probably silly/ignorant questions.
I generally pride myself in being able to do research on my own, but there seems to be so many factors invloved in a properly setup solar system that I cannot know for sure what it all means, so please keep that in-mind ?

OK, let me get started.
This is not my solar system, but my fathers. He has a house (Finca) in Mallorca, Spain. A few weeks after purchasing the house he did a complete upgrade of the solar system as the old one was, well, old and was a 3kWh system I believe. The new system is a 8kWh system and 90% of the items were replaced with new hardware (Batteries, PanEli’s, inverted etc etc), he spent around 23.000€ on this (And yes, he got multiple quotes before deciding on who to use and this one was actually in the mid range of quotes.)

The reason I’m actually posting this is due to me and my father believing the system seems strange (To us at least).
It can be a great day, 100% bright sun all day in summer and the sun setting after 9:30pm, systems shows 100% full etc etc.
Yet, after a few hours, the system shows at 98% or 95% (Which is great), but yet, the generator kicks in due to the Voltage being too low, under 23v or 24v (cannot recall to be honest) The generator lasts maybe 1-2 hours at a time.
Now to me, that’s confusing, especially due to the fact that the average consumption during the day and evening according to the reading on the monitor is +-400W, this powers basic things such as the fridge, computer, some lights etc. The water is heated via gas and has a pen lite battery starter, the oven and hob are both gas, no electricity connection what so ever, no kettle used, no toaster, nothing that had a big “drain” from what I can tell. And anything that does use lots of power is not connected at night (pool pump and borehole pump)

So my question, does this seem normal, shouldn’t the system be able to last longer on an average night? Also, whats the actual point of having a monitor system that shows %, but one can not really ever go below lets say 95% at nights? During the days if its overcast, but enough to generate some power one can see the system maybe show 75% or so, but don’t think we have ever seen it under that.


*Ive attached a few images I took of the setup (Internal elements) as Im not even sure how to best explain it all. The panels are in 2 locations (roof and garden), there are a total of 12 - 400W panels on the roof and 6 - 400W panels in the garden.
So thats a total of 4800W + 2400W = 7200W


= = = = = = = =
Really hope the above makes sense and that my thinking behind solar/how it should work is not completely silly.
Thanks in-advance! ?
 

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he oven and hob are both gas,
If there is a "GlowBar" then that will use a nasty amount of juice, I tossed a beautiful Caloric(TM) Chef's stove because of the glowbar.
This is a 24V system that should be capable of delivering up to 6000 Watts+surge. 6000W÷230VAC = 26A (uncorrected for inverter inefficiency, I believe Victron is 93%. It varies a little depending on model. 3rd Tier "value grade" products are usually 82-88% efficient.

There is no way to tell what the batteries are. Make Model and specs are required to make any comment on them. Link to product is best.
The RED FLAG is the Generator kicking in early, it looks like it is incorrectly programmed It appears to be kicking in far too early BUT this depends on what batteries you have and their capacity.

With the solar exposure & hours you have. that system could easily support 50kWh of LFP storage.

With LEAD Batteries you can only use 50% of capacity without causing harm.
Technical REF LINK: https://batteryuniversity.com/article/bu-403-charging-lead-acid
An excellent user GUIDE: https://www.solacity.com/lead-acid-battery-care/

Watts To Amps Table (At 220V)
Watts:Amps (at 220V):
200 Watts to amps at 220 volts:0.91 Amps
300 Watts to amps at 220 volts:1.36 Amps
400 Watts to amps at 220 volts:1.82 Amps
500 Watts to amps at 220 volts:2.27 Amps

Quick rounding: 2 Amps @ 220VAC: 0.44 kilowatts, 440 Watts, 440,000 milliwatts

LINK Smart Conversion Tables (very handy to have): https://www.inchcalculator.com/electrical-property-conversion-calculators/

Hope it helps, Good Luck
 
Those seem to be flooded lead acid batteries. At rest voltage, 23/24V you mention is too low and would have the generator kick in. I'm not sure how much a drop that specific load you have causes (been too long since I did lead acid...). In any case, I think it's either that your batteries are not fully charged and the SoC indicator is off (and the charge controller is not correctly configured preventing the batteries from charging), or the generator kicks in too early based on an (incorrect?) voltage measurement.
 
Those batteries don't look new at all, looks like a big leakage at some point, my guess would be, that under load you are having under voltage on the battery bank and the generator kicks in.
 
Agreed with @shavermcspud

By the looks it does look the batteries are older. By 'new': do you mean they are recently installed, or do you mean your father installed them new a few years ago?

Cables, insulation and copper busbar on the terminal looks like it's been there for a while, or has been oxidated by eg gas from the cells.
The cables/terminals on the shunt look even worse to me.

I would check all connections, and run a huge load and see what the voltage is on the cells directly.
Inverter should handle 8k, so see if you can pull 3-4kW or so. In theory it should last 2 hours, but you have to check the cell specs for their current rating and calculate the effect of the peukert component to see the actual capacity. But still, 3-4kW should run 5-10min without too much voltage drop if the cells are ok
 
Those batteries don't look new at all, looks like a big leakage at some point, my guess would be, that under load you are having under voltage on the battery bank and the generator kicks in.
Hi, thanks for the feedback.
The leak you see there is from the old batteries, the same platform/location was used where the new setup is done. I was actually at the house the day the van dropped off the batteries and they were definitely new, wrapped up and all. I was however surprised how ”cheap” they looked, especially when compared to what was there before. The new ones looked very budget ?
 
Agreed with @shavermcspud

By the looks it does look the batteries are older. By 'new': do you mean they are recently installed, or do you mean your father installed them new a few years ago?

Cables, insulation and copper busbar on the terminal looks like it's been there for a while, or has been oxidated by eg gas from the cells.
The cables/terminals on the shunt look even worse to me.

I would check all connections, and run a huge load and see what the voltage is on the cells directly.
Inverter should handle 8k, so see if you can pull 3-4kW or so. In theory it should last 2 hours, but you have to check the cell specs for their current rating and calculate the effect of the peukert component to see the actual capacity. But still, 3-4kW should run 5-10min without too much voltage drop if the cells are ok
From what I could tell when they installed the setup, they kept some of the old wiring etc, but lots was replaced too, they had left all the old wiring and hardware behind for us to dispose of once done.

When you say to run a huge load. During the day when the sun is out it works as expected. We tested it by having a few things on at the same time and believe we were close to 4-5kw and all was good, the displ;aged showed that even with that load the panels were generating more than enough.

Do you mean that on a huge load, it should last 2 hours at night?
I asked my father to look at the specs of the batteries, and all he can find on any invoice etc is the following details:
ACUMULADOR 10 OPZS 1550AH C5
 
Those seem to be flooded lead acid batteries. At rest voltage, 23/24V you mention is too low and would have the generator kick in. I'm not sure how much a drop that specific load you have causes (been too long since I did lead acid...). In any case, I think it's either that your batteries are not fully charged and the SoC indicator is off (and the charge controller is not correctly configured preventing the batteries from charging), or the generator kicks in too early based on an (incorrect?) voltage measurement.
My thought is that something is not setup correctly.
My first red flag was when the technician came over to finalize the setup, he was doing it all via his laptop. But the issue was that this took him over 5 hours, he was going back and forth to his van looking for the right cable for some reason and to me this all seems strange. I cannot imagine someone who knows what they are doing taking so long to setup something. He didn’t do any hardware setup as such, it was all on his computer. Unless its normal for something like this to take long?
 
If there is a "GlowBar" then that will use a nasty amount of juice, I tossed a beautiful Caloric(TM) Chef's stove because of the glowbar.
This is a 24V system that should be capable of delivering up to 6000 Watts+surge. 6000W÷230VAC = 26A (uncorrected for inverter inefficiency, I believe Victron is 93%. It varies a little depending on model. 3rd Tier "value grade" products are usually 82-88% efficient.

There is no way to tell what the batteries are. Make Model and specs are required to make any comment on them. Link to product is best.
The RED FLAG is the Generator kicking in early, it looks like it is incorrectly programmed It appears to be kicking in far too early BUT this depends on what batteries you have and their capacity.

With the solar exposure & hours you have. that system could easily support 50kWh of LFP storage.

With LEAD Batteries you can only use 50% of capacity without causing harm.
Technical REF LINK: https://batteryuniversity.com/article/bu-403-charging-lead-acid
An excellent user GUIDE: https://www.solacity.com/lead-acid-battery-care/

Watts To Amps Table (At 220V)
Watts:Amps (at 220V):
200 Watts to amps at 220 volts:0.91 Amps
300 Watts to amps at 220 volts:1.36 Amps
400 Watts to amps at 220 volts:1.82 Amps
500 Watts to amps at 220 volts:2.27 Amps

Quick rounding: 2 Amps @ 220VAC: 0.44 kilowatts, 440 Watts, 440,000 milliwatts

LINK Smart Conversion Tables (very handy to have): https://www.inchcalculator.com/electrical-property-conversion-calculators/

Hope it helps, Good Luck
Hi Steve_S,

Thanks for your reply.
Im not going to lie, I probably got a % of what you are probably explaining to me. ?
What I can answer is the following:

1. The only battery details I can find are: ACUMULADOR 10 OPZS 1550AH C5, not much in terms of brand etc ?
2. The stove has no electrical connection at all, Nico plug so to say. Its all gas powered and even gets started with a match for both the over and stove. Old school ?

I really do appreciate the info and the links. I will need to do some more “research” so that I can actually understand more about all this. I guess thats why one makes use of professionals and people who knows whats happening. It just seems hard to find people on the island that really “know” what they are doing. The after service is something that really lacks in Mallorca, rather crazy!
 
I also just wanted to send a message to everyone thats replied and that will still reply. Thanks again! Every bit helps, and I hope I can get to the bottom of this in some way, as my father would be over the moon knowing that he can safely watch TV after dark and not worry about a huge generator kicking in for 1-2 hours, especially when in his mind 100% means he has peace of mind. I guess I should just tell him to think of that 100% as 10% ?
 
Small update, my father just sent me a close up of the top of the battery. It shows a GNB stamp/logo. Ive googled GNB, but from what I can see, none of ther batteries look like the ones my father has. So not sure of these are GNB batteries, of if the installers just used a GNB cap of sorts? Not sure if thats a thing even.
 

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How old is the stuff? If recently installed I would call in the installer to fix it

As for the load test: Just disable the solar, disconnect wires or so. That allows you to fully draw the energy from the cells. If the cells are bad, and there is sufficient solar, the solar will probably power the stuff... If there is a way to disconnect (Either by a switch or disconnecting a wire) you can test the actual provided power from the cells.

For the cells: If I look locally, i find cells from Hoppecke which seems similar. They also mention 'previously known as OPzV bloc' so there probably is some similarity between those and yours:

However, there is something strange with the capacity...
Its a 24V set, thus 8 cells. Assuming each cell is 370Ah, that would result in 24x370= 8.8kWh

The invoice is mentioning 1550Ah cells.. That would result in 24x1550 = 27kWh of capacity.

If they charge you for the 27kWh cells, and deliver smaller 370Ah / 8.8kWh.. there is something wrong.

The 370Ah cells retail here for approx 375 eur/piece (OPZV series)
The OPZS series look different and have higher capacity: https://stroomwinkel.nl/catalogsearch/result/?accu_spanning=1408&battery_type=266&q=Hoppecke+

Doing some small calculations with the available stuff I can find here:
16x180 = 2880 (solar panels approx 400-450wp each)
8x375 = 3000 (Cells)
Victron 24/8000 3600
MPPT 250/70 800
Victron touch screen 300

Total 11.6k

By the looks, everything else looks re-used. So add some mounting stuff and so on, I think the material costs are 15k in total.

Leaves 8k for labour?? That's a nice profit....

If they actually did use the 1550Ah cells, assuming around 850/cell, that would be 19k or so on materials...
And 4k for labour and profit would sound a nice profit, but that's not out of the ordinary. (I expect it takes 2 days to install and wire everything, so labour adds up nicely. I also expect 500-1000 eur for shipping from mainland spain)

I suspect them to invoice different cells than they actually delivered

Note: Those OPVZ stuff is on other vendors as well:

But on all datasheets, the bigger cells (Especially 1500Ah+) seem to have 4 terminals. Your's showing 2. That does match the lower capacity cells specs, and the calculations. So they at least seem to have listed the wrong model on the invoice. If you actually paid for it...


Edit: Found the cells from the invoice. They indeed are Hoppecke

Those are NOT the ones on your images
 
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Thanks @DJSmiley,
My father is putting things together for me at the moment, so I thought I would add what I have now too. I still need to go over your costs, but from what I could see at a glance I think its pretty much whats listed on the invoice. I have attached some parts of the invoice, my father did however send in 5 parts. These prices however don’t include the other 6 panels in the garden, as that was installed a few months later, as before those additional panels were installed they had issues with the generator kicking in during the day too, if the weather was not fully sunny all day long.

As for age:
This was fist installed July 2020, so its over a year old. The issue is that from the start it seems like it was not “right”, but getting answers of service from installers was no easy task. According to them its all good and operating as it should. My father Nore I were in the position to say otherwise, as we are not the professionals and dont know the facts. All we knew/though was that who would want solar if after spending over €23k one has issues like this. The costs of diesel, people coming to service/check it etc etc. Seems silly to have solar as it ends up more costly and more of a hassle. And to me this seemed strange. ?


One thing too note, here in Mallorca/Spain the charge 21% IVA on-top of the bill, so prices are a bit steep here compared to other places I believe.
 

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Prices I found here locally were also including VAT. First look the invoice is pretty similar from what I've found, except they have these prices listed as ex VAT.. .so that's +20% more than the prices I found.
The battery price matches the 350-370Ah cells, I think they mistakely listed as 1550Ah. Price and images don't look like 1550Ah.

First impression is the invoice looks pretty OK to me. Approx 1500 in labour, 6 panels less, but the SMA included (I didn't list it). Slightly more on parts for mounting, wires and so on than I initially guessed but not unrealistic)

And yes, beeing 20-25% more expensive compared to a webshop is pretty common for many installers. They can't match prices from shops which only takes 10 eur profit..

In the end, it all looks pretty ok, but the non-working part should have been fixed by them.

Note: Cells look like they are wet cells, you might need to top-up them occasionally. (Even more if the chargers aren't setup properly and overcharging). Setup should be able to provide that 400W load for a full day or so without any sun at all if the cells are OK.

I'd start with measuring to see if a wire/connection is crap, or the cells are dead. As said, disable solar charging (or test at night), so all energy is pulled from the cells. Run 4kW load for 10min and check.
 
Prices I found here locally were also including VAT. First look the invoice is pretty similar from what I've found, except they have these prices listed as ex VAT.. .so that's +20% more than the prices I found.
The battery price matches the 350-370Ah cells, I think they mistakely listed as 1550Ah. Price and images don't look like 1550Ah.

First impression is the invoice looks pretty OK to me. Approx 1500 in labour, 6 panels less, but the SMA included (I didn't list it). Slightly more on parts for mounting, wires and so on than I initially guessed but not unrealistic)

And yes, beeing 20-25% more expensive compared to a webshop is pretty common for many installers. They can't match prices from shops which only takes 10 eur profit..

In the end, it all looks pretty ok, but the non-working part should have been fixed by them.

Note: Cells look like they are wet cells, you might need to top-up them occasionally. (Even more if the chargers aren't setup properly and overcharging). Setup should be able to provide that 400W load for a full day or so without any sun at all if the cells are OK.

I'd start with measuring to see if a wire/connection is crap, or the cells are dead. As said, disable solar charging (or test at night), so all energy is pulled from the cells. Run 4kW load for 10min and check.
Yes, understandable. Like you said, from what one can see on invoice compared to online seems fair, especially when keeping the 21% IVA on top of it all ?

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: Cells look like they are wet cells, you might need to top-up them occasionally. (Even more if the chargers aren't setup properly and overcharging). Setup should be able to provide that 400W load for a full day or so without any sun at all if the cells are OK.
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Regarding the above, my father has the fill up system. He does however manually open and close the valve, as if left open the water does tend to “boil” over during hot days. So he manually checked every day to ensure the little white float is at the top and if not, he opens the valve for a while to let enough distilled water in to have them all perfectly filled. So I think thats being sorted already ?

Ill see, maybe ill go over today, see if there is a “safe” way for me to disconnect the solar/charger and then do as you said, run the system at abou 4kW for 10min and see if it lasts and what it says on the screen there after. I am guessing that if the system is “working correctly” we should be able to run for 10min at 4kW and not have the generator kick in during those 10min?

Then, as a bit of a random question. What would be the number 1 change one could do if one wanted to have a system that could last even longer? I assume replacing the batteries is number 1? What’s recommended? If thats even something one can ask.

Thanks again!
 
Then, as a bit of a random question. What would be the number 1 change one could do if one wanted to have a system that could last even longer? I assume replacing the batteries is number 1? What’s recommended? If thats even something one can ask.
The answer is simple but it makes some people butts pucker up after having already spent a pile of cash.
Any/All Lead Based batteries can only be drawn down to 50% DOD otherwise they are being killed. And BTW, Almost every 1st solar system with Lead Batteries, the owners kill then prematurely... It is so common, it is an expected default.

Simply Put, LFP Lithium Iron Phosphate (LiFePO4) for a residential ESS Pack/Bank.
99% efficient as opposed to 80% +/-. Charges faster and can take higher amperage to charge.
Can be discharged for thousands of "full cycles" to 90% and still work after 10 years.
They do not explode or catch fire, they do not offgass anything (unless failure of course).
They are virtually maintenance free once configured & installed...no watering or any such nonsense.
LFP optimal temps are the same as for Human Comfort, No charging below 0C, Limited charge (.25C) to 10C and from 10C-50C 0.5C charge rate.
Can discharge without ill effect to -20C.
They are also Smaller, Lighter than Lead (not major issue in residential in any case).
Domestic AVailability in Spain ? No Clue, I'm sorry. I am in Canada, Spain is a tad out of my neighbourhood.

24V LFP requires 8 Cells in Series, 1 BMS (Battery Management System) case & fuse.
24V/280AH = 7,168Wh or 7.16kWh.
24V/304AH = 7782Wh or 7.72kWh.
Multiple packs in parallel divide & share Load & Charge, each can operate independently if others cut off (matched & configured packs is best) but this also provides Fail Over protection if something does go wrong.
*BMS Spec*
I would recommend 300A Discharge Capacity Smart BMS and derate that to 250A for safe margin. My personal preference is fr Realy/Contactor controlled BMS as opposed to FET Based controls. EV's and all heavy DC use Relays of SolidState Contators due to reliability and high amp handling safely.
Fused to 300A ! (allowing for Surge Potentials)

Fully Matched & Batched Cells with Test Report, provided by Luyuan Tech, well established known good reliable vendor.
Delivery Destination used for Guess-Timator set to Spain. For a proper shi[ping quote a Chat Session must be done.
Click on Thumbnail to enlarge images
304AH's firstm then 280AH's
1637843978835.png1637844138288.png
The Shipping Shown is NOT accurate, A Chat/Messenger session is required with Amy to get a proper shipping quote.
SOURCE: Luyuan https://szluyuan.en.alibaba.com/productlist.html?spm=a2700.shop_pl.88.14

FYI Shipping to EU can go Boat, Air or Rail but there is pros/cons to each... Air for cells etc = Ludicrous !

BMS recommendations would require more info.
Most popular in use currectly, JBD, JK/Heltec, QUCC (some have Realy/Contactor and FET based BMS'. Some have Passive Balancing while other Active Balancing and assorted Features & Functions. Myself I use Chargery BMS8T-300A with SolidState Contactors for my productions packs within my 30kWh LFP bank.

Hope it helps, Good Luck.
 
The cells installed are no regular lead-acid (AGM, gel) but are full traction batteries. Those have a much longer lifespan and can be discharged below 50%.
Full traction batteries have a much ticker plates, which provides longer lifespan and longer lifetime. Cons are the price and weight.

I agree I personally would prefer LFP, but especially these are a decent option, and for some specific cases somtimes even preferred (eg charging in cold temps - you don't have to work around low temp issues by using heating and so on)
Benefits of LFP are as you said, longer lifetime, less maintenance, higher capacity with high loads (no peukert effect), ability to charge with much more amps and so on.

I don't agree on the 'ALL lead acid 50% max)'. Yes, you can assume that for the majority of used batteries for storage/RV usage, but not all.

The ones TS is using are eg similar to these from Enersys:

Up to 6950 cycles to 20% depth of discharge, 2200 cycles to 60% DoD and 1500 cycles to 80% DoD

1637845107770.png
 
if the system is “working correctly” we should be able to run for 10min at 4kW and not have the generator kick in during those 10min?

I’ve read all this and I’d say the five hour setup time and the no-overnight battery life indicate three possibilities, maybe all three:
1) something is NOT RIGHT with the batteries; either got ripped off or an idiot technician
2) true heavy/deep lead acid batteries can provide pretty stinkin’ good service. You didn’t apparently get good service right out of the gate. It’s either the batteries or the charge controller programming.
3) the generator trigger points are not programmed properly.

You either need to figure out the software yourself and post here for setup advice, or you need a reputable solar electrician that likes solar systems and setup, because it sounds like the last guy/installer likes money but not working systems.
 
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