Solar generation in rain/cloudy conditions

Thank the heavens for good pv at the moment. For us solarphiles, pattern recognition can save the day where many less attentive would only discover an issue when the next bill arrives.

Earlier in the week one morning I immediately noticed on the graph my 4kw geyser spiking out of control. Immediately started feeling the bathroom walls for warm spots as I had a hot water pipe burst inside the wall last year which was an expensive nightmare. Sure enough the walls were warm without any taps having been run - panic stations! Traced the problem downstream which ran outside to a separate building and managed to pinpoint the rough area of the leak which was somewhere underground and not visible at all. Luckily that building now has its own 2kw geyser and so doesn't rely on the original setup. I got my plumber to just cap the old pipe outside and he will connect up the new setup next week at a far lower cost than blasting through what would have been ~R200 a day from the grid alone powering a runaway geyser pumping hot water into the dirt. My PV had no hope of keeping up but luckily spotted the issue on day one so closed inlet and switched it off at the db. Crisis averted.
 
@Neuk - what size array do you have?

Using the car charger to use up the spare PVs , yet it looks like the peak output of my 9.3kwp array is about 39 kWh a day.

a24c3ce550c27ffb61d2bec6e0ac9af1.jpg
 
TedLasso said:
@Neuk - what size array do you have?

Using the car charger to use up the spare PVs , yet it looks like the peak output of my 9.3kwp array is about 39 kWh a day.

a24c3ce550c27ffb61d2bec6e0ac9af1.jpg
Click to expand...

13.5kWp but maxing out at around 9kWp at the moment.

P.S. Edit to add that on a good summers day our olde 8.7kWp array could do 50kWh.
 
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TedLasso said:
@Neuk - what size array do you have?

Using the car charger to use up the spare PVs , yet it looks like the peak output of my 9.3kwp array is about 39 kWh a day.

a24c3ce550c27ffb61d2bec6e0ac9af1.jpg
Click to expand...
Guess orientation plays a big part. I have some issues with space, so my one string only starts full production around 11h00 at the moment. Bit earlier in summer and bit later in winter. 9.6kwp maxing out at around 43kwh. I'm sure I could do 55 to 60 if both started around 9.

Wanted to split that string but then I'd potentially have issues with voltage start up.
 
Hazy_Living@79 said:
Guess orientation plays a big part. I have some issues with space, so my one string only starts full production around 11h00 at the moment. Bit earlier in summer and bit later in winter. 9.6kwp maxing out at around 43kwh. I'm sure I could do 55 to 60 if both started around 9.

Wanted to split that string but then I'd potentially have issues with voltage start up.
Click to expand...
There is a plan, in the next year to ditch my solar heating panels for pool and to move the PV2 array of 8x600w panels there to get the good stuff from early in morning.
 
Hazy_Living@79 said:
Guess orientation plays a big part. I have some issues with space, so my one string only starts full production around 11h00 at the moment. Bit earlier in summer and bit later in winter. 9.6kwp maxing out at around 43kwh. I'm sure I could do 55 to 60 if both started around 9.

Wanted to split that string but then I'd potentially have issues with voltage start up.
Click to expand...

Yep, we have two strings facing NE and one NNW but with two panels facing W. We have a lot of high trees on the E side of our house which shade the two NE strings in the early morning. It is worse in winter than summer but still plays a major part in the maximum PV production we can make.
 
We had a 9 hour power failure on Monday from around 12:00 to 21:00, so used o.1kWh of mains supply that day and used more battery, meaning yesterday we managed to make a decent amount of PV kWh,,,

1787736172725.png

Overnight load is getting less and less with the warmer temperatures so I am slowly rolling back keeping batteries at 100% in the evenings.
 
Neuk_ said:
We had a 9 hour power failure on Monday from around 12:00 to 21:00, so used o.1kWh of mains supply that day and used more battery, meaning yesterday we managed to make a decent amount of PV kWh,,,

View attachment 1932359

Overnight load is getting less and less with the warmer temperatures so I am slowly rolling back keeping batteries at 100% in the evenings.
Click to expand...
Ey, I made the last 2 digits of your PV generation.

WhatsApp Image 2026-08-26 at 13.01.06.jpeg
 
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