My journey to renewable energy - Solar

Priapus

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/soobs

Very nice OP. I've wanted solar for years but the hoops you have to jump through are apparently a nightmare with COJ/City Power.

Which reminds me, are you seperating your "grid" DB from your solar DB? I read some time ago you had to have the two "grids" separated to stop backfeeding.

P.S what system are you using for energy monitoring at DB level?

I’m not sure what regulations you’re referring too. Would you mind pointing them out to me? The regulations I’ve checked and seen implemented at my neighbors place (Did their solar install in March) - who has a COC are not strenuous or difficult to meet and seem reasonable.

As for the DB power monitoring; it’s a sensor that clips over the main feed coming into the DB and feeds the data to a sonoff device that home assistant and grafana get values from. Then it’s a matter of just representing that data in a nice graph.

/subs

@Tander, what are your costs looking like?

All said and done - around 80k including the install

From my understanding of the regulations that they have, you have to have a separate solar DB that runs off your solar system. This would be for things like lights, computers and fridges etc. Then you have to have a Grid DB for heavy loads like oven and geyser. This forces you to size up the solar system as high as possible with batteries so you never have your solar DB off.

I think you can get around this by having a transfer switch between the two DB's... but this sort of defeats the purpose of true hybrid PV generation that blends seamlessly with the grid supply.

I believe you’re misinformed. I’ve seen many other systems installed with COC,s not having to jump through such hoops. As mentioned I’d love to see these regulations if you know where they are?
 

wingnut771

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From my understanding of the regulations that they have, you have to have a separate solar DB that runs off your solar system. This would be for things like lights, computers and fridges etc. Then you have to have a Grid DB for heavy loads like oven and geyser. This forces you to size up the solar system as high as possible with batteries so you never have your solar DB off.

I think you can get around this by having a transfer switch between the two DB's... but this sort of defeats the purpose of true hybrid PV generation that blends seamlessly with the grid supply.


Cheap to start and expandable. If you look at a system like Enphase has you can also do batteries independently of the solar system. So long as the panels/inverters can communicate with the battery inverter you're golden (This is actually how Tesla's PowerWall 2 does it apparently too).
afaik, the only reason to split the db is to isolate the heavy load from solar just to keep costs down, and has nothing to do with regulations, but you do need a way to isolate the inverter. you're more than welcome to spend extra and size your solar to accommodate those loads aswell, but then costs (mainly batteries) go through the roof.
micro inverters are not cheap so i would disagree with you that it's to keep costs down. one micro inverter (2 to 4 panels, 600W-1200W) is about R3000, and is usually for grid-tie with no batteries, if you're not planning to feed back then you still need batteries and another inverter to connect AC from micro inverter to charge DC batteries afaik.
 
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Speedster

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afaik, the only reason to split the db is to isolate the heavy load from solar just to keep costs down, and has nothing to do with regulations, but yoy do need a way to isolate the inverter. you're more than welcome to spend extra and size your solar to accommodate those loads aswell, but then costs (mainly batteries) go through the roof.
micro inverters are not cheap so i would disagree with you that it's to keep costs down. one micro inverter (2 to 4 panels, 600W-1200W) is about R3000, and is usually for grid-tie with no batteries, if you're not planning to feed back then you still need batteries and another inverter to connect AC from micro inverter to charge DC batteries afaik.
Indeed. I really don't get the hype behind micro-inverters for a residential setup, especially so if you factor in load shedding.

Regarding the inverter size. Most homes have the bulk of their power usage during daylight hours (lawnmower, vacuum, food prep etc) so that there is merit in a largish inverter with PV and a smaller battery. The battery only has to large enough to get one through the night which, for most households, isn't all that much. In my case, a strong option is an 8kW inverter, 4kW panels and, for a start, 3.5kWh battery as our night time usage is reasonably low. I'm am though on the hunt for an Efergy Engage Hub to confirm our peak and night time usage.
 

wingnut771

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Indeed. I really don't get the hype behind micro-inverters for a residential setup, especially so if you factor in load shedding.

Regarding the inverter size. Most homes have the bulk of their power usage during daylight hours (lawnmower, vacuum, food prep etc) so that there is merit in a largish inverter with PV and a smaller battery. The battery only has to large enough to get one through the night which, for most households, isn't all that much. In my case, a strong option is an 8kW inverter, 4kW panels and, for a start, 3.5kWh battery as our night time usage is reasonably low. I'm am though on the hunt for an Efergy Engage Hub to confirm our peak and night time usage.
not if you're in durban trying to sleep at night during summer without an aircon. :ROFL:
 

DeShizz

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I’m not sure what regulations you’re referring too. Would you mind pointing them out to me? The regulations I’ve checked and seen implemented at my neighbors place (Did their solar install in March) - who has a COC are not strenuous or difficult to meet and seem reasonable.

My bad, looks like I got confused by this thread some time ago. Confirmation bias FTW!

So this means grid-tie is fine - if you want to export, you need to go on to TOU tariffs (which seem fine except for Winter Peak - R4 per kwh - ow!) otherwise you need to set up some kind of backfeed prevention mechanism.

Lastly, in that same thread, is the following statement still true? " No system will be allowed to be connected to a pre-paid meter even if the system will have zero exporting."
 

Priapus

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My bad, looks like I got confused by this thread some time ago. Confirmation bias FTW!

So this means grid-tie is fine - if you want to export, you need to go on to TOU tariffs (which seem fine except for Winter Peak - R4 per kwh - ow!) otherwise you need to set up some kind of backfeed prevention mechanism.

Lastly, in that same thread, is the following statement still true? " No system will be allowed to be connected to a pre-paid meter even if the system will have zero exporting."

Yes, that last bit is true. Solar on pre-paid is an issue. But guys do, do it. As for the back feeding, The setup will have very very minimal back feeding, not enough to turn a light bulb on I believe. I have no ambitions to travel down that road. Happy to let the excess energy generated go to "waste" until I get enough storage for it to run the house in the evenings on the Pylontechs.
 

Priapus

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So the install has started early. :D

My current DB in the house is too small to house the extra cabling and switches we have to add. So, it was time to upgrade from a 16-way to a 24 way board.

The guys have got an early start on this and have decided to run the cables needed first (Not connecting them) and get the difficult part done now in preparation for the weekend.
IMG_4915.jpeg IMG_4917.jpeg

The new DB will house the changeover switch:
067D0649-3C90-4F80-982E-E03D8D93B489.jpg

We are running 10m2 cabling from this DB to the garage, where the Inverter, batteries and a smaller DB will sit. Hence the need to cut the wall up to add more conduit piping.

More pictures to follow in the next few days.
 

Priapus

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R80k is not bad at all. Would you mind giving a rough breakdown of what that entails?

Sure.

- Inverter: 12k
- Pylontech Battery: 20k
- Panels - around 2k ea - total 24k
- Cabling, switches, fuses, conduit, combiner box etc - 15k or so
- Mounting for 12 panels on pitched roof - 5k
- Install - 6k (Through a family member's business)
 

eye_suc

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Ahhh ok that makes more sense. Your install was a bargain!

I went the Victron way, so my inverter is more than double yours :(
Also 2 x Victron MPPT and Victron Venus GX.
 

TedLasso

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So the install has started early. :D

My current DB in the house is too small to house the extra cabling and switches we have to add. So, it was time to upgrade from a 16-way to a 24 way board.

The guys have got an early start on this and have decided to run the cables needed first (Not connecting them) and get the difficult part done now in preparation for the weekend.
View attachment 890784 View attachment 890786

The new DB will house the changeover switch:
View attachment 890796

We are running 10m2 cabling from this DB to the garage, where the Inverter, batteries and a smaller DB will sit. Hence the need to cut the wall up to add more conduit piping.

More pictures to follow in the next few days.
That's interesting and thx for sharing .I have the same issue as you in my DB in passage with stuff going in garage (planned).

Never thought existing DB could be extended but now have a solution to consider, even if very messy .
 

Priapus

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Ahhh ok that makes more sense. Your install was a bargain!

Oh yeah, saving big time on the install. Another quote I had for the install was around 15k.

I went the Victron way, so my inverter is more than double yours :(
Also 2 x Victron MPPT and Victron Venus GX.
Nice setup! :D

I'd have loved to get the Victron unit, however it was just out of my budget. Decided to go bigger on panels and battery instead.

Inverter can always be changed easily enough down the line if it does not meet my needs or has issues.
 

Priapus

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That's interesting and thx for sharing .I have the same issue as you in my DB in passage with stuff going in garage (planned).

Never thought existing DB could be extended but now have a solution to consider, even if very messy .

Yeah and surprisingly not difficult to do. Just messy. A new DB was R700 or so. Not expensive. I am a bit OCD in the sense that I wanted all the breakers to match. So replacing those older style ones you see in the middle of the DB with newer CBI ones.
 

eye_suc

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Oh yeah, saving big time on the install. Another quote I had for the install was around 15k.


Nice setup! :D

I'd have loved to get the Victron unit, however it was just out of my budget. Decided to go bigger on panels and battery instead.

Inverter can always be changed easily enough down the line if it does not meet my needs or has issues.
I just took a screenie to show you your panels will be doing just fine:
2020-08-11 13_58_58-Window.png

Just clocked 4500+W. In this weather, with my shitty setup. Your North facing roof should be doing better than this I think.
 

AchmatK

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I just took a screenie to show you your panels will be doing just fine:
View attachment 890882

Just clocked 4500+W. In this weather, with my shitty setup. Your North facing roof should be doing better than this I think.
Are you in CT?

My setup had been running since the beginning of the month so keen to compare my solar generation.

I'm in Somerset West and got peaks off 5.2 kW in this weather.

Currently just over 10 kWh produced for the day. Also just past 200 kWh solar production for the month.

Current capacity is 21 x 305w Canadian solar panels tied to a sunsynk 8kw hybrid inverter and 3 x 3.5 kWh pylontech batteries.
 

Neuk_

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I just took a screenie to show you your panels will be doing just fine:
View attachment 890882

Just clocked 4500+W. In this weather, with my shitty setup. Your North facing roof should be doing better than this I think.

Would you mind sharing what Victron equipment you have? I notice that your Remote Console lists AC Loads and Critical Loads which mine doesn't at the moment which may be a setup difference.
 

Lupus

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Sure.

- Inverter: 12k
- Pylontech Battery: 20k
- Panels - around 2k ea - total 24k
- Cabling, switches, fuses, conduit, combiner box etc - 15k or so
- Mounting for 12 panels on pitched roof - 5k
- Install - 6k (Through a family member's business)
Not bad on the install price, a few places are 15k for the panels and the electrical work.
 

eye_suc

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Would you mind sharing what Victron equipment you have? I notice that your Remote Console lists AC Loads and Critical Loads which mine doesn't at the moment which may be a setup difference.
I think that is just a configuration difference. My lounge aircon, oven and geyser is "AC Loads" while everything else falls under "critical". We did make a few changes to my existing DB board just to split the loads.
 
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