Generator or Inverter for residential use?

AchmatK

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Plus you can now manage base load as well as charge batteries on overcast days.
I'm going to get flamed again soon for spamming this thread but it's nice to compare now that I have a full year of data even though the system was not optimised fully.

21 x 305w panels vs 34 x 305w panels. 6.405kw vs 10.37kw. Same day with almost similar conditions. Can also now start to monitor any panel degradation as they age. Ideally I should have produced 34.32kwh today if I look at what I got from the 21 panels a year ago. The extra panels do hoever have a small section that gets shaded an hour in the morning so I'm quite satisfied with the numbers. Screenshot_20210802-173048_SOLARMAN%20Business.jpg Screenshot_20210802-173129_SOLARMAN%20Business.jpg
 

AchmatK

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The 6 additional panels were installed in the blue section and I have space in the red section for about 14 additional panels but will need to trim some of the neighbours trees that overhangs the carport. Screenshot_20210802-174608_Maps.jpg
 

RonSwanson

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I'm going to get flamed again soon for spamming this thread but it's nice to compare now that I have a full year of data even though the system was not optimised fully.

21 x 305w panels vs 34 x 305w panels. 6.405kw vs 10.37kw. Same day with almost similar conditions. Can also now start to monitor any panel degradation as they age. Ideally I should have produced 34.32kwh today if I look at what I got from the 21 panels a year ago. The extra panels do hoever have a small section that gets shaded an hour in the morning so I'm quite satisfied with the numbers. View attachment 1119092 View attachment 1119094
My solar anniversary date comes up on the 26th of this month. A rough look at my figures now, the first 4-6 months I was really just messing around. I needed that time, and the whole experience, to realise what it was that I actually wanted. I also took a look at my original projections on the PVWatts modelling tool, to understand my mindset at the time, and it's very interesting how it all evolved.
I have you and the other like-minded forumites to thank for where I am today. Everyone's input and sharing has challenged a lot of my own thoughts, beliefs and ways of doing things, and I have grown a lot over the past year. Thank you for your sharing!
 

Tariqe

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pv production was 23.6 kWh yesterday from the 6.4 kWp array,
interesting fact, hit 11.6 kWh yesterday briefly on the 5 kW Sunsynk, inverter did not sound an alarm or shut down
 

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AchmatK

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pv production was 23.6 kWh yesterday from the 6.4 kWp array,
interesting fact, hit 11.6 kWh yesterday briefly on the 5 kW Sunsynk, inverter did not sound an alarm or shut down
That's actually interesting as my 8kw inverter gives a fault if I exceed 11kw. The pass through was changed to 50A.

My grid usage is slowly dropping and expecting it to be zero by mid August. Got it down to under 10kwh today. 20210803_204342.jpg
 

RonSwanson

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That's actually interesting as my 8kw inverter gives a fault if I exceed 11kw. The pass through was changed to 50A.

My grid usage is slowly dropping and expecting it to be zero by mid August. Got it down to under 10kwh today. View attachment 1119804
A new record for you. I just barely managed to increase mine to around 13-14 kWh/day :)
 

buyeye

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Nov 28, 2010
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This is mine yesterday, it's not impressive if you know that I had to manually change the settings just before midnight to set it to use the battery and change over to utility just before the geyser come on at night.
 

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BigBear

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GA Solar? Anyone used them recommended?

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MockTurtle

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Mar 29, 2007
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my diy job last weekend. (12x345w monos, 3s4p). ...effectively doubling my pv to 8kwp.
yeah angle is not ideal that its on a flat carport. but at least its facing north and i didn't need a ladder to do the install. the old (4kw) existing string is on the 2nd floor roof (facing nne at 25 deg pitch).
...now i should be able to better fill up my batteries (14.4kwh) even in winter. 4kwp panels were actually sufficient during height of summer.
 

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AchmatK

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Is it just me or are there more complaints this year on local Facebook groups about getting less units when buying in prepaid.

Seems like every Somerset West group has a few complaints every week about how little units they get.
 

Botha22

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Is it just me or are there more complaints this year on local Facebook groups about getting less units when buying in prepaid.

Seems like every Somerset West group has a few complaints every week about how little units they get.
Electricity tariffs went up and people can't be bothered to check on the Eskom or municipality website.
 

AchmatK

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Inverter never fails to deliver.

Not sure how an 8kw inverter can generate in excess of 9kw. Currently using 6.45kw to charge the batteries and 2.54kw to run the loads.

I think the DC(pv high voltage) to DC(48v for battery charging) conversion is different to the DC(pv/battery) to AC(load). Screen_Recording_20210824-131926_SOLARMAN%20Smart~2_2.gif
 

Neuk_

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Inverter never fails to deliver.

Not sure how an 8kw inverter can generate in excess of 9kw. Currently using 6.45kw to charge the batteries and 2.54kw to run the loads.

I think the DC(pv high voltage) to DC(48v for battery charging) conversion is different to the DC(pv/battery) to AC(load). View attachment 1133152

If I understand your post, your inverter is only inverting 2.54 kW from DC to AC, far below it's rated capacity of 8kW.
 

AchmatK

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If I understand your post, your inverter is only inverting 2.54 kW from DC to AC, far below it's rated capacity of 8kW.
Which is what I'm thinking it is doing and that's why the 8kw inverter is capable of having 10.5kw of solar panels.
 

Neuk_

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Which is what I'm thinking it is doing and that's why the 8kw inverter is capable of having 10.5kw of solar panels.

That depends on the MPPT in the inverter and not the inverter capacity itself but I presume that the thinking behind a larger capacity MPPT than the inverter capacity is to account for losses and provide overhead to handle load and battery charging.
 

maxxis

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Jul 26, 2007
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I finally have the details of my system.

Quite old from the looks of it.
16 panels
Think Power S4400TL inverter

The manual says the system ties into the grid. No mention of additional battery backup capabilities etc.

Right now we generate 15 to 20kw per day and as a result the little wheel on the old meter spins in reverse during the day effectively building up a reserve for us in the grid to use at night.

Total units used in a day is about 3 to 5.

Any way to add a backup to the house for loadshedding without changing the inverter?

I have a high current input into the DB that connects to my generator. It has it's own switchover lever for when the generator is connected to the house.

Worth looking at adding something like a large UPS that I can keep connected to the house to stay charging and then using using the same switchover lever that the generator would use when the power is out?
 

ADrunkTeddyBear

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Jul 22, 2014
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Inverter never fails to deliver.

Not sure how an 8kw inverter can generate in excess of 9kw. Currently using 6.45kw to charge the batteries and 2.54kw to run the loads.

I think the DC(pv high voltage) to DC(48v for battery charging) conversion is different to the DC(pv/battery) to AC(load). View attachment 1133152
I think the Sunsynk 8kW can take in 10kW worth of solar (DC)

Although, the actual DC - AC unit can handle 8K only.

Leaving the remainder (2kW for the DC bus which will go to charge the battery)
 
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