Solar Journey House

[HowTo]

This brings us to September, production.
House was ok.



Flat, I jumped the gun.
Imported 10kW. Cloud cover had me worried.





This is where higher kW panels are better, especially in cloud covered days.
Flat 460W and 470W panels.
House 550W panels.

 

[leon.davibe]

This brings us to September, production.
House was ok.

View attachment 1762373

Flat, I jumped the gun.
Imported 10kW. Cloud cover had me worried.


View attachment 1762375


This is where higher kW panels are better, especially in cloud covered days.
Flat 460W and 470W panels.
House 550W panels.

Imo

higher wattage isn't what makes panels perform better in cloudy conditions

Correlation isn't causation

Higher voltage does make a difference

The relationship between mppt voltage range and aray voltage is what makes or breaks the output in certain scenarios

Especially with 550w normally 50v 72/144 cells vs 460
Often 460 are 41v 60/12 cells

Landing you with smaller/bigger mppt range and thus affects production
Especially early morning and late afternoon

Panel count on flat?

 

[HowTo]

OK here are Oct 24 usage figures.

House

Flat, did some importing 5kW.

 

[HowTo]

Imo

higher wattage isn't what makes panels perform better in cloudy conditions

Correlation isn't causation

Higher voltage does make a difference

The relationship between mppt voltage range and aray voltage is what makes or breaks the output in certain scenarios

Especially with 550w normally 50v 72/144 cells vs 460
Often 460 are 41v 60/12 cells

Landing you with smaller/bigger mppt range and thus affects production
Especially early morning and late afternoon

Panel count on flat?

12

Most panels you buy today are all 144 cells. I still maintain a 5kW inverter you can't install grater panels over 500W.
You could exceed inverter fresh hold.
That is why mine are all 460 and 470 wat panels.

 

[leon.davibe]

12

Most panels you buy today are all 144 cells. I still maintain a 5kW inverter you can't install grater panels over 500W.
You could exceed inverter fresh hold.
That is why mine are all 460 and 470 wat panels.

yes on same cell count/voltage panels lower wattage will give better shade resistance as panel count goes up

shadding patterns and string composition would play a role too

ie if you use a 650w 41v panel, you would be able to put them all in series on a sunsynk to the tune of 11 in a row
that would net you 7150w array netting you a 330v vmp on a hot day, you would be able to withstand the loss of 6.66 panels to shade before dropping out of mppt range and losing the string ie you have 60.5% shade resistance

now split he same array in two 3575w strings not to exceed max voc , with 51v panel lets say 7 x 500w now the vmp voltage is 259v on a hot day you have 135v shade protection that would be approx 3.33 panels so your shade resistance is then 47%

now yes the fact that you have two strings shading patterns can lift that percentge
just an example sucked out of my thumb

 

[leon.davibe]

otr lets do 5500w 12 panels is too much for one string so you split in 2

so you have 6 in s tring with a vmp of 222v 97v shade resistance, so shade resistance of 2.33 panels so shade resistance is then 38.8% naturally 2 strings could lift again

while the same closest size in the 650w 41v variant would be 8panels 5200w or 9 panels 5850w
they would all be in series 240/270v netting you a shade resistance of 115/145v


and thus shade resistance would be 3.66/4.66 panels so 45.75% / 51.77% shade resistance

 

[Koosvanwyk]

yes on same cell count/voltage panels lower wattage will give better shade resistance as panel count goes up

shadding patterns and string composition would play a role too

ie if you use a 650w 41v panel, you would be able to put them all in series on a sunsynk to the tune of 11 in a row
that would net you 7150w array netting you a 330v vmp on a hot day, you would be able to withstand the loss of 6.66 panels to shade before dropping out of mppt range and losing the string ie you have 60.5% shade resistance

now split he same array in two 3575w strings not to exceed max voc , with 51v panel lets say 7 x 500w now the vmp voltage is 259v on a hot day you have 135v shade protection that would be approx 3.33 panels so your shade resistance is then 47%

now yes the fact that you have two strings shading patterns can lift that percentge
just an example sucked out of my thumb

Not sure I follow the logic here?

Shading does not have a big impact on volts produced. While it does impact the volts of the string the impact is very little, less than say what the impact of heat is on the Volts.

If you are close to the lower end of the MPPT range then yes, shade might cause you to drop in and out of the range, but this is a very fine margin given the limited impact that shade has on volts. Most often it might even have the opposite impact as the suddend reduction in the temperature of the panel will increase the volts.

Shading impact current (amps) which does obviously not impact the MPPT voltage range.

 

[leon.davibe]

Not sure I follow the logic here?

Shading does not have a big impact on volts produced. While it does impact the volts of the string the impact is very little, less than say what the impact of heat is on the Volts.

If you are close to the lower end of the MPPT range then yes, shade might cause you to drop in and out of the range, but this is a very fine margin given the limited impact that shade has on volts. Most often it might even have the opposite impact as the suddend reduction in the temperature of the panel will increase the volts.

Shading impact current (amps) which does obviously not impact the MPPT voltage range.

If a panel is in shade or a portion of it normally they are divided into 3sections

Then that section/panel gets bypassed via diodes when this happens it contributes 0v to the string so yea a 30vmp panel each section produces 10v and thus each section that disappears due to shade reduces the voltage by said 10v and 30v per panel

That is why they do half cut panels to help

Since the one half can still keep the voltage up and the amps just get halved as the one half is disabled it just contributes half the amps

So no shading does affect voltage modern panels just mitigate the impact a lot better

 

[leon.davibe]

explainer video and then my PV voltage graph on a day with no shading

and then one with afternoon some shading stints
my monitoring archive is every 10S so it catches the spikes and dips
with some monitoring solutions with lower resolution a person may miss the spikes and dips if they don't coincide
with the snapshots every 5 minutes on sunsynk data

 

[HowTo]

Al I can say look at the spec sheet of the inverter.
It will tell you maximum input capacity.
If you exceed that maximum, you will damage the inverter.
That is why maintain look at the maximum capacity the inverter can handle.



6*460 = 2760
6*470 = 2820 Total 5580 Safe.....!!!!

if I do 12*550 Total 6600 will f.ck my 5kW inverter. This is bit risky.

 

[leon.davibe]

Al I can say look at the spec sheet of the inverter.
It will tell you maximum input capacity.
If you exceed that maximum, you will damage the inverter.
That is why maintain look at the maximum capacity the inverter can handle.

View attachment 1774453

6*460 = 2760
6*470 = 2820 Total 5580 Safe.....!!!!

if I do 12*550 Total 6600 will f.ck my 5kW inverter. This is bit risky.

i wasn't suggesting you put your 51v panels in series
merely indicating that panel cell count and voltage selection can be consideed during initial setup

the important one to heed is the max voltage that is what burns controllers many controllers will just clip a stronger array
ie if you install an array more than the input wattage thge most you will get out of them is the rated wattage

many people install slightly larger arrays and then get more early morning and late afternoon and just have wasted capacity mid day
now yes i agree it is better to keep within all thresholds for dsafety sake

and then i was just adressing the fact that shading affect voltage

 

[HowTo]

i wasn't suggesting you put your 51v panels in series
merely indicating that panel cell count and voltage selection can be consideed during initial setup

the important one to heed is the max voltage that is what burns controllers many controllers will just clip a stronger array
ie if you install an array more than the input wattage thge most you will get out of them is the rated wattage

many people install slightly larger arrays and then get more early morning and late afternoon and just have wasted capacity mid day
now yes i agree it is better to keep within all thresholds for dsafety sake

and then i was just adressing the fact that shading affect voltage

"And then i was just addressing the fact that shading affect voltage" not a problem at my installation.

Also, all my 6 string panels are series based.

 

[HowTo]

Morning all

Nov 24 production house.


Flat Nov 24


This month loots of cloud cover.

 

[HowTo]

Im currently in Zambia. Will return in May.

House for Jan and Feb usage.



Flat usage for Jan and Feb 2025.


I'm still around.

Will return to Zambia in June 2025 to escape winter in ZA.
In winter Zambia winter approx. 12 Degrees and high of mid 20.

 

[HowTo]

House production figures.
March 2025


Flat production figures March 2025

 

[HowTo]

I'm having a weird problem with my 8Kw sunsynk inverter.
For the last week I lost the Wi-Fi connection for some reason.
Reason is still unclear. Eventually found the problem.
Long story short, every time the inverter LCD panel goes into sleep mode it switches the Wi-Fi connection off.
With help from sunsynk I disabled the sleep mode. (Under basic settings)
You would not know how many times with the help from the app I enabled the Wi-Fi.
Sunsynk wants me to send the inverter in for repair. Not shure if this is a programming glitch, firmware?
The time for repair between 6 and 18 weeks.
That means I have to run the house on Esdom power. Just looking at the cost.

I'm replacing it tomorrow with an 8Kw Deye inverter.
My installer will take the sunsynk inverter for repair.

 

[HowTo]

Sunsunk 8KW inverter out and 8kW Deye inverter in.
I also received a COC for work done.

Pic New Deye inverter



No more lots of cooling fans.

Old Deye spec sheet:


New Spec Deye inverter

 

[HowTo]

Milestone so far on my solar installation House.

Installation date: 2022-08-13

This is before I switched to 8Kw Deye inverter.

 

[HowTo]

House Usage for Nov25

On the Deye app