Solar generation in rain/cloudy conditions

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denmendez65

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Hi All,

For those with solar at their homes. How much of your rated KWp of your installed panels are you getting? Peak figures would be fine. And how much energy have you generated today?

This is mainly for people in JHB as the weather is pretty bad today but even historical figures from others outside of JHB is fine. Just curious how other people's systems are coping.

I have an installed panel capacity of 4.55KWp and have hit at most 350W from the panels today (Won't get any higher considering the time now). This is inline with the 5 to 10% generation I see in weather like this for other systems. Yesterday I was on average around 1.5KW despite the clouds so the cloud cover today is definitely much thicker.
 
Neuk_ said:
We peaked at 6.8kW today when clouds went away, we have 8.7kWp but with less than ideal orientation, only generated 8.5kWh today.
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Lucky you. It looks like night time on my side of JHB. Very overcast and the sun never showed face.
 
denmendez65 said:
Hi All,

For those with solar at their homes. How much of your rated KWp of your installed panels are you getting? Peak figures would be fine. And how much energy have you generated today?

This is mainly for people in JHB as the weather is pretty bad today but even historical figures from others outside of JHB is fine. Just curious how other people's systems are coping.

I have an installed panel capacity of 4.55KWp and have hit at most 350W from the panels today (Won't get any higher considering the time now). This is inline with the 5 to 10% generation I see in weather like this for other systems. Yesterday I was on average around 1.5KW despite the clouds so the cloud cover today is definitely much thicker.
Click to expand...
Got 10,7kW peak installed, today's peak has been 3.7kW @ 11:00. It produced 10kW/h thus far today and 24kW/h yesterday.
On a nice cloudless summer day, it can hit >50kW/h.
 
LCBXX said:
Got 10,7kW peak installed, today's peak has been 3.7kW @ 11:00. It produced 10kW thus far today and 24kW yesterday.
On a nice cloudless summer day, it can hit >50kW.
Click to expand...
Consistent with @Neuk_ considering you both have similar intalled capacity except his peak is higher because of location and your generation is a tad bit higher.
 
denmendez65 said:
Consistent with @Neuk_ considering you both have similar intalled capacity except his peak is higher because of location and your generation is a tad bit higher.
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I'm for sure not getting the batteries charged beyond 32% today. I'm down to 560w coming from the panels. Got about 6.4kW/h stored as of now and that's going to be depleted by 20:00.
1758803463135.png
 
LCBXX said:
I'm for sure not getting the batteries charged beyond 32% today. I'm down to 560w coming from the panels. Got about 6.4kW/h stored as of now and that's going to be depleted by 20:00.
View attachment 1851027
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I am about 275W from the panels. Makes sense as I have basically half your array. I do have way less load than you based on some of your previous posts so I can push my batteries with current weather for about 4 days before it becomes a problem.

I dont have the geyser on the inverter though which you do, thats the only load not on the inverter as that will be on a separate system and probably a gas geyser inline with it if the Geysertech is not enough to heat in this kind of weather. Installing 2.1KWp for the geyser alone.
 
9.2 installed, peak for all of 5 minutes was 3.5. Sitting at 9.7kWh generated. With geyser and dishwasher ran today used 2%. It's just not moving past 64%, it did reach 72% while the dishwasher was running.
 
Lupus said:
9.2 installed, peak for all of 5 minutes was 3.5. Sitting at 9.7kWh generated. With geyser and dishwasher ran today used 2%. It's just not moving past 64%, it did reach 72% while the dishwasher was running.
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So you can run another day then without Eskom with weather like this? Impressive considering you heat your geyser with the inverter.
 
denmendez65 said:
So you can run another day then without Eskom with weather like this? Impressive considering you heat your geyser with the inverter.
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Nope can run till tomorrow, as there is a 30% drop overnight.
So will make it through to tomorrow but geyser is off and should retain enough hot water for two showers tomorrow morning. Hopefully we have sun
 
Lupus said:
Nope can run till tomorrow, as there is a 30% drop overnight.
So will make it through to tomorrow but geyser is off and should retain enough hot water for two showers tomorrow morning. Hopefully we have sun
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Weather report says sun so hopefully thats the case.
 
Peaked at 6.69kw, but that was exceptionally brief. It managed a sustained 3.5kw for about 45 minutes.

I've managed to generate 11.4kwh today. This is just enough to recharge the battery to full, meet the house load, and reheat the geyser after the morning showers.

9.6kwp in Midrand.
 
Thanks for the responses.

I think I will add 3 more panels to my current 4.55KWp array and stick to the 4 panels for the geyser. That will push me to 8.6KW. If I can get 10 plus kWh a day in such weather as your systems, then I will not need a generator at all, considering that at the moment I can drop my energy demand to under 6kwh and still be comfortable enough to have charged batteries and live a normal life.

The current configuration might give me issues after 4 days of weather like today. I average 10kWh a day for the house without the geyser when all the pumps are running outside. I will install a gas geyser if need be, for continuous days like today, for water heating.

Thanks again for the responses.
 
Looks like I'll probably go into the evening with 62 to 65% will see when it cuts over if it does.
This is twice my old system size and 65% would technically be 130% my old one and I used to go down to 30% on it.
 
Zuner said:
Dunno what i was smoking now when i saw that graph, but here you can decide what the actual average is:

View attachment 1851050
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Compared to your load I think you are more than fine with the PV area you have. Between 9 and 12 was nice. After that you were mostly still above your load. Your base load seems to be around 300W.
 
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