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Long time admirer, now for the plunge

Featured Replies

  • Author
22 minutes ago, tetrasection said:

Just to clarify, are you planning on exporting to the grid?

no, that is not on the cards. I believe that I will need a new energy dispenser. Not sure the cost will be worth it.

  • Author
7 minutes ago, gooseberry said:

you're limited to 3.5kW generation capacity

Is that to say that you cannot legally generate more than 3.5kW and hour for local consumption? (I do have a 60A breaker)

29 minutes ago, gooseberry said:

Even if you're not exporting, if your main breaker is 60A you're limited to 3.5kW generation capacity on Eskom or several municipalities like CoCT. 4.6kW if you're on a 80A breaker.

I think this is incorrect. You are only limited in how much you can charge your batteries from the grid, either by software or hardware limits. At least for CoCT as daar as I know. There is no limit on solar generation except for the current 1MW or proposed new increased limits. 

23 minutes ago, Saliegh said:

Is that to say that you cannot legally generate more than 3.5kW and hour for local consumption? (I do have a 60A breaker)

I think he is mistaken and it refers to the limit you can charge your batteries from the grid. 

1 hour ago, Achmat said:

Also if you have space for additional panels, make sure that you can add them easily if you decide to add more

or at east add the rails for the additional panels now and as budget allows add the panels ( even two at a time ), since yours is a single story house, you might even be able to add the panels yourself( with some help, of course)

30 minutes ago, Achmat said:

I think he is mistaken and it refers to the limit you can charge your batteries from the grid. 

https://resource.capetown.gov.za/documentcentre/Documents/Procedures%2C guidelines and regulations/Requiremenst for Samll-Scale Embedded Generation.pdf

COCT.thumb.png.8e3d986b2a4cf7869b12ca84e8ca81ee.png

NRS 097 -2 -1

NRS.thumb.png.f5b03974b33a23ecbf4f88758e9f3103.png

It's the GENERATION capacity that is limited, not the charge current

Edited by gooseberry

12 minutes ago, Tariq said:

in 9 months of operation, have not had to use grid charge anyway !!!!!

Same. Mine is set to never charge from grid. Only once when I missed the load shedding notification and my batteries did not charge in time did i do a manual grid charge. 

57 minutes ago, Saliegh said:

no, that is not on the cards. I believe that I will need a new energy dispenser. Not sure the cost will be worth it.

In that case I don't see the need for that many panels. Rough calculation from what you've told us (650kwh/month) your average load is less than 1kw. So with over 6kw of panels you would be discarding most of your solar generation. That is unless you have disproportionately larger loads during the day?

Edited by tetrasection

Just now, Achmat said:

I'm certain that this was discussed on this forum and the interpretation was that generation capacity limits in this document is incorrect. 

I will see if I can find it. 

This forum would be wrong, the documentation is very clear on this.

1 minute ago, gooseberry said:

You can have more PV if they're only connected to an off-grid circuit. But you can't grid tie a larger peak generation capacity than those limits.

Which flies in the face of what is currently being approved by CoCT themselves. 

@Tariqhas a 5kw inverter and more than the limits in pv. He does not feed in to the grid as he has a normal prepaid meter and the inverter is not a separate off grid circut. This was approved by CoCT. 

  • Author
51 minutes ago, tetrasection said:

In that case I don't see the need for that many panels. Rough calculation from what you've told us (650kwh/month) your average load is less than 1kw. So with over 6kw of panels you would be discarding most of your solar generation. That is unless you have disproportionately larger loads during the day?

There is definitely a larger load during the day... pool pump, aircon, washing machine, etc. Overnight is probably <3kW 

6 minutes ago, Saliegh said:

There is definitely a larger load during the day... pool pump, aircon, washing machine, etc. Overnight is probably <3kW 

You also need to size for winter solar generation instead of summer. Pv generation in winter can be 50% less. In summer I was getting over 55kwh per day from pv. 

Winter on a clear day like yesterday in Cape Town i only achieved 27kwh from my 10.3kw solar array. 

Use this app for your location. I've found its pretty accurate in estimating what my daily PV generation will be for the next 3 days. 

https://play.google.com/store/apps/details?id=com.exigo.solcaster

i have a 4.3 kWp array, nowadays, winter ( a sunny,cloudless day ), with the geyser chowing down the majority of the pv production, i barely hit 89% soc on the battery

  • Author
8 hours ago, Achmat said:

You also need to size for winter solar generation instead of summer

yeah, I'm starting small, and will grow my system from there. For now, some harvesting and immunity from load shedding is good enough. 

 

8 hours ago, Achmat said:

Use this app for your location

That looks quite nifty. Will help me plan when the big appliances should go on

On 2021/06/03 at 9:11 PM, gooseberry said:

5 on either side each on its own MPPT

I would consider adding at least 8 if you have space. 5 panels might give you less productions during overcast, not enough volts. 

On 2021/06/03 at 9:11 PM, gooseberry said:

5 on either side each on its own MPPT

I would consider adding at least 8 if you have space. 5 panels might give you less productions during overcast, not enough volts. 

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