Hello, I have Sunsynk 5kW hybrid inverter, with a single 5kWh Sunsynk battery (see details below), powered by 8x 505w Longi panels. In total (and in theory), my panels should produce 4040w at peak sun (Panels are all north facing. No major shading from the trees next door. I am in Cape Town). I very rarely get more that 3500w out of the panels (on a sunny day) and I was wondering if there is a way to 'claim' the remaining 500+w.

Is there an inverter setting I need to pay attention to?

Thanks in advance.

8 hours ago, rgt.dnl said:

Hello, I have Sunsynk 5kW hybrid inverter, with a single 5kWh Sunsynk battery (see details below), powered by 8x 505w Longi panels. In total (and in theory), my panels should produce 4040w at peak sun (Panels are all north facing. No major shading from the trees next door. I am in Cape Town). I very rarely get more that 3500w out of the panels (on a sunny day) and I was wondering if there is a way to 'claim' the remaining 500+w.

Is there an inverter setting I need to pay attention to?

Thanks in advance.

Is this a new installation? The conditions to produce close to the peak power are usually mainly present during summer.

31 minutes ago, GreenFields said:

Is this a new installation? The conditions to produce close to the peak power are usually mainly present during summer.

The system was installed in April 2023, so it's been through a full seasonal cycle. I never feel like I am getting the most out of it however and wondering if I need to tweak the settings etc.

9 hours ago, rgt.dnl said:

Hello, I have Sunsynk 5kW hybrid inverter, with a single 5kWh Sunsynk battery (see details below), powered by 8x 505w Longi panels. In total (and in theory), my panels should produce 4040w at peak sun (Panels are all north facing. No major shading from the trees next door. I am in Cape Town). I very rarely get more that 3500w out of the panels (on a sunny day) and I was wondering if there is a way to 'claim' the remaining 500+w.

Is there an inverter setting I need to pay attention to?

Thanks in advance.

You can view the expected irradiance levels here:
https://en.tutiempo.net/solar-radiation/cape-town.html

You can use that and then calculate to your panels to find the closest to forecast real world expectations.

11 hours ago, rgt.dnl said:

Hello, I have Sunsynk 5kW hybrid inverter, with a single 5kWh Sunsynk battery (see details below), powered by 8x 505w Longi panels. In total (and in theory), my panels should produce 4040w at peak sun (Panels are all north facing. No major shading from the trees next door. I am in Cape Town). I very rarely get more that 3500w out of the panels (on a sunny day) and I was wondering if there is a way to 'claim' the remaining 500+w.

Is there an inverter setting I need to pay attention to?

Thanks in advance.

This is the nominal power value under STC (Standard Testing Conditions) meaning 1000w/m2 and 25ºC. If the irradiance is lower or the temperature of the cells is higher, the panel will not produce the same power.

Usually, you never get maximum power in summer because the cells get very hot. It is easier to get maximum power in spring and fall or just after a cloud edge. Sometimes you may even see power values exceeding the maximum nominal if the weather is cold and sunny.

Typical irradiance in winter even on the sunny Highveld is around 600W/m2.
That's around 60% to be expected from the rated panel W.
And as mentioned by @Mauritius B in summer in full sun the panel temps reduce the efficiency
In theory you will never get the rated Watts, that being the reason that a lot of installations have over paneling to make up for these inefficiencies. The danger there being that in cloud edge or cold conditions you may produce more than the rated MPPT values.
An excess of Amps is typically clipped by the MPPT (within limits). It's important though to ensure that the MPPT Voltage is never exceeded.

11 minutes ago, zsde said:

Typical irradiance in winter even on the sunny Highveld is around 600W/m2.
That's around 60% to be expected from the rated panel W.
And as mentioned by @Mauritius B in summer in full sun the panel temps reduce the efficiency
In theory you will never get the rated Watts, that being the reason that a lot of installations have over paneling to make up for these inefficiencies. The danger there being that in cloud edge or cold conditions you may produce more than the rated MPPT values.
An excess of Amps is typically clipped by the MPPT (within limits). It's important though to ensure that the MPPT Voltage is never exceeded.

@zsde I quote you.--- The danger there being that in cloud edge or cold conditions you may produce more than the rated MPPT values.

Here is exactly what you mention regarding cloud edge, yesterday my system 12 X 440 W panels for a short while produced over 5 Kw 

 

Edited June 4, 20242 yr by Antonio de Sa

2 minutes ago, Antonio de Sa said:

yesterday my system 12 X 440 W panels for a short while produced over 5 Kw

Just check your voltage and amps though and you will find that it's the amps that increase and your voltage is still within limits.
My panels are rated for around 13Amps and in summer with cloud edge I have had up to 17Amps. The Inverter rating is 22 Amps so no problem.

17 minutes ago, zsde said:

Just check your voltage and amps though and you will find that it's the amps that increase and your voltage is still within limits.
My panels are rated for around 13Amps and in summer with cloud edge I have had up to 17Amps. The Inverter rating is 22 Amps so no problem.

The voltages are within the MPPT limits, actually far from it, at that stage my PV voltages were 260 V the current was slightly over 11 Amps, the highest current that I have saw in my system was just over 12 Amps. 

Edited June 4, 20242 yr by Antonio de Sa

@Antonio de Sa, @zsde, @WannabeSolarSparky, @Mauritius B Thank you. This is brilliant. I have some work to do to understand all of this relative to my setup and all the guidance here is very much appreciated. Thanks.

18 hours ago, rgt.dnl said:

Hello, I have Sunsynk 5kW hybrid inverter, with a single 5kWh Sunsynk battery (see details below), powered by 8x 505w Longi panels. In total (and in theory), my panels should produce 4040w at peak sun (Panels are all north facing. No major shading from the trees next door. I am in Cape Town). I very rarely get more that 3500w out of the panels (on a sunny day) and I was wondering if there is a way to 'claim' the remaining 500+w.

Is there an inverter setting I need to pay attention to?

Thanks in advance.

Are you still currently getting 3500w from a 4040w array? I am in Northern Suburbs and barely get above 2000w from a 4.5kw array so if you getting 3500w than that amazing.

I get 1800-1900w from a 3,2kw array on a clear cold autumn day in the southern suburbs

5 minutes ago, AndrewJdc said:

I get 1800-1900w from a 3,2kw array on a clear cold autumn day in the southern suburbs

Thats decent enough. On Sunday past which was fairly clear my highest sustained was 2063w, had a 2 min spike of 2350w as well. Expected it to drop further until the end of the month as well but hopefully not by much.

Edited June 4, 20242 yr by CTskollie

4 hours ago, CTskollie said:

Are you still currently getting 3500w from a 4040w array? I am in Northern Suburbs and barely get above 2000w from a 4.5kw array so if you getting 3500w than that amazing.

@CTskollie I think I've overstated that somewhat. In May I got a brief peak of 3750w but mostly get between 2k-3k on average based on what I can see in Sunsynk Connect. Solar Assistant concurs. Quite puzzled how I got those numbers considering the forecast was partly cloudy with rain on May 7th in Cape Town.

“Quite puzzled how I got those numbers considering the forecast was partly cloudy with rain on May 7th in Cape Town”

That actually makes sense.

Though devastating for total daily kW hours, you probably will get your highest peaks, even if short, on days of intermittent cloud, because of lower day temperatures and periods of cloud edge reflection.

I get normal sunny day peaks of 3100w this time of the year, on 3600w capacity up here in Joburg. The fact that Joburg is sunny in winter is not applicable because we are talking about peaks, not daily kWh. What is applicable is the further north aspect, but numbers should still be in the same bal park. Which they seem to be. I got a high peak of 3500w last week when the cold front was passing. Partly cloudy with low temperatures.

But the thing that makes most sense for me to chase is not peak generarion, but total daily kWh.

This link below should give you an idea of how much kWh you should be getting (provided the load and battery are accepting all the offered power all day) per day for every kW of installed capacity.

https://profilesolar.com/locations/South-Africa/Cape-Town/#:~:text=Solar output per kW of installed solar PV by season in Cape Town&text=Average 8.98kWh%2Fday in,3.56kWh%2Fday in Winter.

These are averge numbers based on climate, so are obviously weather dependent. On a winter’s day when the sun does shine all day, you should be getting about 4 times installed capacity in Cape Town: (very roughly). 

Edited June 6, 20242 yr by Kwaaikat

7 hours ago, Kwaaikat said:

 

https://profilesolar.com/locations/South-Africa/Cape-Town/#:~:text=Solar output per kW of installed solar PV by season in Cape Town&text=Average 8.98kWh%2Fday in,3.56kWh%2Fday in Winter.

 

Thanks for sharing the link. This seems to be one of the better resources that unlike some are not as pessimistic for winter yields and close to my actuals. 

I like the 42 places listed on the same page. 

20 minutes ago, Scorp007 said:

Thanks for sharing the link. This seems to be one of the better resources that unlike some are not as pessimistic for winter yields and close to my actuals. 

I like the 42 places listed on the same page. 

Thanks I only stumbled on it today because of this. For my setup so far it as is close to spot on as can be, taking into account it works on average weather.

36 minutes ago, Kwaaikat said:

Thanks I only stumbled on it today because of this. For my setup so far it as is close to spot on as can be, taking into account it works on average weather.

I did use it over 3 yrs ago but lost track of the addy. It hardly came up with searches. Glad to have it saved now.