Planning a solar system

No, don't think we have that. Here's a pic of our main DB box

Main-DB-s.jpg

I'm assuming the red wire to the left of the picture is where I need to clamp the Efergy meter once I get it since that cable goes to the distribution box inside the apartment we have. The whole thing looks kinda like a huge mess to me.
 
Crusader said:
No, don't think we have that. Here's a pic of our main DB box

View attachment 1228436

I'm assuming the red wire to the left of the picture is where I need to clamp the Efergy meter once I get it since that cable goes to the distribution box inside the apartment we have. The whole thing looks kinda like a huge mess to me.
Click to expand...
You got three phases there so you'd need 3 clamps...
 
richjdavies said:
You got three phases there so you'd need 3 clamps...
Click to expand...
Yeah, but I don't want to measure the power for the entire property, only the usage for the apartment which seems to be on one phase.

Might add more clamps later to measure the rest. Initial plan is to get just the apartment over to solar this year.
 
Crusader said:
Yeah, but I don't want to measure the power for the entire property, only the usage for the apartment which seems to be on one phase.

Might add more clamps later to measure the rest. Initial plan is to get just the apartment over to solar this year.
Click to expand...
Understood... And nothing else on that phase, fair enough...
 
Seems I misunderstood the colour scheme of the wiring and that the apartment also gets 3 phase power (red + blue + white wire is each a seperate phase.)

Would there be a way to measure power usage using just the 1 CT clip until I can get 2 more?
 
Crusader said:
Seems I misunderstood the colour scheme of the wiring and that the apartment also gets 3 phase power (red + blue + white wire is each a seperate phase.)

Would there be a way to measure power usage using just the 1 CT clip until I can get 2 more?
Click to expand...
What kind of meter do you have?
 
Crusader said:
The one pictured in the first post on this page (https://mybroadband.co.za/forum/threads/planning-a-solar-system.1170490/post-28713050) which just goes to a normal distribution box inside the apartment. The red + blue + white wires in the top right of the image are the ones that goes through to the apartment distribution board.

Not sure how things look inside the distribution board.
Click to expand...
Right... That's old old!
Options:
1. Stick with efergy and CTs and understand it won't be accurate (or do they take voltage too now?). How much are efergy CTs now
2. Get a meter for the apartment then read that.. (3 phase direct (100A) meters aren't too expensive... But then depends how you read it (e.g. raspberry pi or homebug)
3. Rewire so it's simpler... All on one phase or apartment all on one phase... Theoretically/physically simple (where they go in just put them all on red phase)- but regulations make it harder -- they won't like blue wires with red phase power on...
4. Not for you... Pulse count etc. the existing meter (with a pi or ebug)
 
richjdavies said:
Right... That's old old!
Options:
1. Stick with efergy and CTs and understand it won't be accurate (or do they take voltage too now?). How much are efergy CTs now
2. Get a meter for the apartment then read that.. (3 phase direct (100A) meters aren't too expensive... But then depends how you read it (e.g. raspberry pi or homebug)
3. Rewire so it's simpler... All on one phase or apartment all on one phase... Theoretically/physically simple (where they go in just put them all on red phase)- but regulations make it harder -- they won't like blue wires with red phase power on...
4. Not for you... Pulse count etc. the existing meter (with a pi or ebug)
Click to expand...
Yeah, I don't understand how the apartment isn't on one single phase. Not sure what happens with all 3 phases when it gets to the apartment distribution box. Are they combined into one somehow? My electrical knowledge is zero.

I've ordered two extra clamps for the Efergy, but they'll only arrive in the 2nd week of February. Stock seems to be on backorder everywhere.
 
I'm looking at possibly getting 10 or 12 x 540W JA Solar Mono Perc solar panels. We have a flat corrugated iron roof with a slope of around 25° downward from E to W.

The roof is approx 12m x 8m. With the 12m side facing North. Would this be big enough to accommodate 12 panels?

When calculating power production do tou use 5.5h for daylight? So the 12 x 540W x 5.5 = 35.64 kW a day.
 
Crusader said:
I'm looking at possibly getting 10 or 12 x 540W JA Solar Mono Perc solar panels. We have a flat corrugated iron roof with a slope of around 25° downward from E to W.

The roof is approx 12m x 8m. With the 12m side facing North. Would this be big enough to accommodate 12 panels?

When calculating power production do tou use 5.5h for daylight? So the 12 x 540W x 5.5 = 35.64 kW a day.
Click to expand...
I’d say 4.6 is more realistic, that’s been my average at least. Not the most optimal panel arrangement unfortunately.
 
Crusader said:
I'm looking at possibly getting 10 or 12 x 540W JA Solar Mono Perc solar panels. We have a flat corrugated iron roof with a slope of around 25° downward from E to W.

The roof is approx 12m x 8m. With the 12m side facing North. Would this be big enough to accommodate 12 panels?

When calculating power production do tou use 5.5h for daylight? So the 12 x 540W x 5.5 = 35.64 kW a day.
Click to expand...
Yeah, that's what is used, you sometimes get more but generally between 4.5 and 6 hrs is the most productive period.
 
Crusader said:
I'm looking at possibly getting 10 or 12 x 540W JA Solar Mono Perc solar panels. We have a flat corrugated iron roof with a slope of around 25° downward from E to W.

The roof is approx 12m x 8m. With the 12m side facing North. Would this be big enough to accommodate 12 panels?

When calculating power production do tou use 5.5h for daylight? So the 12 x 540W x 5.5 = 35.64 kW a day.
Click to expand...
Get the spec sheet of those specific panels and check their sizes. I almost came short with my available space.
 
W@P said:
Get the spec sheet of those specific panels and check their sizes. I almost came short with my available space.
Click to expand...
According to spec sheet they are about 2.2m x 1.1m. Not sure how much space is needed between them.

Guessing 5 panels could go next to each other on the 12m side.
So 2 x rows of 5 panels each + 1 row with 2 panels. Not sure how string layout will be done.

Or 3 rows of 4 panels...
 
Crusader said:
According to spec sheet they are about 2.2m x 1.1m. Not sure how much space is needed between them.

Guessing 5 panels could go next to each other on the 12m side.
So 2 x rows of 5 panels each + 1 row with 2 panels. Not sure how string layout will be done.

Or 3 rows of 4 panels...
Click to expand...
About 2cm.
 
TheChamp said:
About 2cm.
Click to expand...
Will they have to be elevated somehow towards the north or would the 25 degree slope of the roof be enough? Surely if they are elevated there needs to be more distance between the rows so they don't cast a shadow on the next row of panels.
 
Crusader said:
Will they have to be elevated somehow towards the north or would the 25 degree slope of the roof be enough? Surely if they are elevated there needs to be more distance between the rows so they don't cast a shadow on the next row of panels.
Click to expand...
True, I forgot about the almost flat roof,
The angle will depend on your location, there are calculators you can use but it's typically around 25 to 35 degrees.
 
TheChamp said:
True, I forgot about the almost flat roof,
The angle will depend on your location, there are calculators you can use but it's typically around 25 to 35 degrees.
Click to expand...
Sadly the roof slopes in the wrong direction, from East to West and not towards the North. So it seems likely that they will have to be elevated towards the North. So much stuff to consider, once I get closer to actually getting quotes etc. I'm hoping the installers will know their stuff.
 
I know this is just half the picture and only one day, but quite informative usage info.
Looks like we are using 11 kW in a 24 hour period on this phase. I'm guessing that can be doubled to 22 kW to include a guesstimate of the 2nd and 3rd phase.

What would be viewed as the time you use the batteries from? Would it be from 17:00 to 08:00 and then solar is from 08:00 to 17:00?

8 kW usage from 17:00 to 08:00. It looks like if we are going to be able to run the aircons at night we'll need at least 3 Hubbles. But I'll wait until I have accurate stats after the other 2 clips get here. (And I'm aware one single day is a very poor data point).

Hourly Power Usage.png
 
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