Hi everyone,

Longtime lurker, first-time poster.

I’m based in Joburg and am starting to look seriously at installing a solar/battery backup system for our home. I’ve learned a huge amount from reading through this forum already, but I still have a few questions before pulling the trigger.

The goal is to build as much energy independence as possible without completely blowing the budget. Ideally, I’d like to keep the total installed cost under around R150k if possible.

We currently average somewhere between 15–20kWh per day, although that has only been monitored over roughly a month since we recently moved in, so I realise that may still change. I have been trying to monitor a bit more accurately with the Itron municipal panel installed and the max draw I have seen is just under 6kW(+- 5.8 - 5.9)

At the moment I’m thinking along the following lines:

• 10–12kW inverter (currently considering Sunsynk or Deye)

• 15–20kWh battery capacity (not sure which battery brands are considered best value/reliability)

• 10–12 x ~600W panels (again, unsure on best brands/specs)

A few technical questions:

1. My understanding is that most inverter setups separate “essential” and “non-essential” loads. If something like a geyser is connected to the non-essential side, does that mean it can still use solar power during the day but will never draw from the batteries? Or is the non-essential side always purely grid powered?

2. I often see people using batteries of identical sizes/capacities in parallel. Is there a technical reason for this? For example, is it a bad idea (or even possible) to combine something like a 15kWh battery with a 5kWh battery?

3. Any general thoughts on the proposed setup above would be greatly appreciated, especially whether it seems appropriately sized for our usage and which products/brands you’d recommend.

And lastly, not sure whether this is against forum rules, but if anyone has recommendations for reputable installers/providers servicing the northern suburbs of Joburg, I’d really appreciate it.

Thanks in advance.

Good evening @Koch903 and welcome to the forum.

See my answers below.

2 hours ago, Koch903 said:

1. My understanding is that most inverter setups separate “essential” and “non-essential” loads. If something like a geyser is connected to the non-essential side, does that mean it can still use solar power during the day but will never draw from the batteries? Or is the non-essential side always purely grid powered?

If the inverter can feed power back into the grid and there is non essential loads connected and there is exess solar power available then the solar power will power the non essential loads if the battery bank is fully charged and if the inverter is setup to do so. With the inverters that cannot feed power back then the non essential loads are powered by utility power.

2 hours ago, Koch903 said:

1. I often see people using batteries of identical sizes/capacities in parallel. Is there a technical reason for this? For example, is it a bad idea (or even possible) to combine something like a 15kWh battery with a 5kWh battery?

Yes the batteries must be identical otherwise there will be problems e.g. lets say that you have a Freedom Won 40/32 and a Freedom Won 60/48 that you want to use with an inverter and the batteries does communicate with the inverter which one are going to communicate with the inverter the 40 or 60 if you decide to use the 40 then by the time that all the energy in the 40 is used the 60 still has some energy left which will never be used and if you decide to use the 60 then the 40 would be depleted and most probably sound an alarm and if the batteries does not communicate with the inverter then there are other problems if voltage settings are used with LiFePO4 batteries.

2 hours ago, Koch903 said:

1. Any general thoughts on the proposed setup above would be greatly appreciated, especially whether it seems appropriately sized for our usage and which products/brands you’d recommend.

The most important piece of equipment in an installation is the inverter because if you decide to purchase a cheap inverter which does not have a parallel capability and later on you want to upgrade and the inverter does not have a parallel capability then another inverter with a parallel capability must be purchased and the cheap inverter must be sold at a loss because it has been used.

For a household which uses up to 40kWh per 24 hours I would suggest a 12kw inverter or a 8kw and later on another 8kw because once you have solar and you see how in works then you realize that you can add this and that to the solar but then you realize that you do not have enough power available to do the upgrades that you want to do.

2 hours ago, Koch903 said:

And lastly, not sure whether this is against forum rules, but if anyone has recommendations for reputable installers/providers servicing the northern suburbs of Joburg, I’d really appreciate it.

Have a look at The Powerforum Store and the brands which they sell and contact them and ask for a recommended installer, otherwise contact @Steve87 or @TaliaB and ask if they are available to do an installation.

Regards

GerhardK83

3 hours ago, Koch903 said:

Hi everyone,

Longtime lurker, first-time poster.

I’m based in Joburg and am starting to look seriously at installing a solar/battery backup system for our home. I’ve learned a huge amount from reading through this forum already, but I still have a few questions before pulling the trigger.

The goal is to build as much energy independence as possible without completely blowing the budget. Ideally, I’d like to keep the total installed cost under around R150k if possible.

We currently average somewhere between 15–20kWh per day, although that has only been monitored over roughly a month since we recently moved in, so I realise that may still change. I have been trying to monitor a bit more accurately with the Itron municipal panel installed and the max draw I have seen is just under 6kW(+- 5.8 - 5.9)

At the moment I’m thinking along the following lines:

• 10–12kW inverter (currently considering Sunsynk or Deye)

• 15–20kWh battery capacity (not sure which battery brands are considered best value/reliability)

• 10–12 x ~600W panels (again, unsure on best brands/specs)

A few technical questions:

1. My understanding is that most inverter setups separate “essential” and “non-essential” loads. If something like a geyser is connected to the non-essential side, does that mean it can still use solar power during the day but will never draw from the batteries? Or is the non-essential side always purely grid powered?

2. I often see people using batteries of identical sizes/capacities in parallel. Is there a technical reason for this? For example, is it a bad idea (or even possible) to combine something like a 15kWh battery with a 5kWh battery?

3. Any general thoughts on the proposed setup above would be greatly appreciated, especially whether it seems appropriately sized for our usage and which products/brands you’d recommend.

And lastly, not sure whether this is against forum rules, but if anyone has recommendations for reputable installers/providers servicing the northern suburbs of Joburg, I’d really appreciate it.

Thanks in advance.

1. Your non essential can indeed be powered from the battery. Key is to reduce the load level in your timer setting for certain times. PV is routed to the non essential side that is the major plus of a hybrid. If you don't want to export to grid it will thus power your high loads like geyser and if there is a short fall this bit would come from grid if you have grid. This can only happen if you have a grid supply. Non essential cannot be supplied if the grid is off.

2. Different sizes and makes and models of batteries can normally not talk to each other that's why one would stick to sizes and models.

3. Deye/Solis and Sunsynk are great units to have.

Thanks for the information and responses.

I guess I need to weigh up the pro/cons of a 12kw inverter now for future flexibility or rather a second 8kw in parallel down the line.

On the point of export to the grid - is this something we can do/viable in Joburg?

My suggestion for a system if i had the choice of starting afresh and looking at your needs would be:

1x Deye 12kw Inverter

1x Dyness 16kWh Lithium Battery PowerBrick Max (note in offgrid mode you'll be limited to 10kw of power from your battery)

12x 620w panels (JA,Longi,Jinko,Trina are all good) out of interest what is the orientation of your roof?

For a system like this you are looking at around R134k ex vat (dependent on your site though)

Re exporting to the grid i am not too au fait with joburg export rules/tariffs, but with the described system if you have an electric geyser/ pool pump and discharge the battery at night i don't see you being able to export much anyway.

Hope this helps.

17 hours ago, Koch903 said:

The goal is to build as much energy independence as possible without completely blowing the budget.

24 minutes ago, Koch903 said:

I guess I need to weigh up the pro/cons of a 12kw inverter now for future flexibility or rather a second 8kw in parallel down the line.

Or else go with a 6kW Solis hybrid at the start, with just one 15kWh battery and 8x600W panels on just one MPPT, and keep the non-essentials on the grid side but powered from the inverter too. That's for a more cost-effective more grid-tied start-up that you could scale up by doubling everything up. Even if you don't, it should already go a long way towards covering the 15-20kWh daily usage with 6kW peak usage on most days. Your usage is not actually that much that a smaller system couldn't handle most of it even if it's sometimes a squeeze. How often is the grid out in your area, though? I'd be leaning towards the 12kW inverter and doubling from the start if grid-independence is the main immediate concern.

21 minutes ago, Mattyboy said:

My suggestion for a system if i had the choice of starting afresh and looking at your needs would be:

1x Deye 12kw Inverter

1x Dyness 16kWh Lithium Battery PowerBrick Max (note in offgrid mode you'll be limited to 10kw of power from your battery)

12x 620w panels (JA,Longi,Jinko,Trina are all good) out of interest what is the orientation of your roof?

For a system like this you are looking at around R134k ex vat (dependent on your site though)

Re exporting to the grid i am not too au fait with joburg export rules/tariffs, but with the described system if you have an electric geyser/ pool pump and discharge the battery at night i don't see you being able to export much anyway.

Hope this helps.

Thanks very helpful - This sounds like a good start and more or less in line with what I was thinking. I was just wondering if it is worth spending slightly more and getting 2x 10kwh batteries to build in some redundancy?

Roof is north facing and no trees to cause shadows - Although I am not sure all panels would fit on the north roof so could put some on the east facing roof (I understand this would allow for earlier generation too). The other option is a flat section of roof on the north side that may be able to fit some panels.

I also had an installer visit that is suggesting a high-voltage Sungrow system. He is suggesting that the high-voltage systems are more efficient and based on newer/better tech, for a minor premium. I am not sure of this and still need to do my research.

My pleasure, The price difference between 10kwh and 16kwh is negligible so 2x 16 kWh would be better value for money. If you wanted a larger battery bank, to best utilise it then more panels would be necessary.

You are fortunate to have that much roof space with no shading! With the 12kw having 3 mppts you have plenty of flexibility.

First prize would be to have all your panels on the north facing, next would be the east facing. I say the east facing as second best because on the flat roof you would want A-frame roof mounts which to my knowledge are quite a bit more expensive than the normal roof mounts,also when you say some are you meaning 3 panels or 6 panels. This is something you will just have to decide when looking at quotes.

When it comes to sungrow, i would say they are slightly better quality and carry a 10 year swop out warranty (i would attribute most of their price to this)

yes as they are an hv system you would incur less losses but at this scale they are negligible imo.

6 hours ago, Koch903 said:

2x 10kwh batteries to build in some redundancy?

15 to 20 kWh per day is not much energy. I estimate you will be energy independant on sunny days with an 8kW inverter and 13kWh of batteries. Redundancy is a function of your essential loads and how long the sun doesn't shine.

8 hours ago, Koch903 said:

Roof is north facing and no trees to cause shadows - Although I am not sure all panels would fit on the north roof so could put some on the east facing roof (I understand this would allow for earlier generation too). The other option is a flat section of roof on the north side that may be able to fit some panels.

Hi Koch, and a belated Welcome to the Forum from me as well.

With three MPPTs I would install 2 x 7 panels facing north, and one x 7 or 8 panels facing east. This way you will have power earlier in the day, and not lose out on the generation in the afternoons. Although I have a 12kW inverter with 3 MPPTs, I have been running with just 2 MPPTs, each being fed by 7 x 575Wp panels, and they are generating more power than we can use on a sunny day (including running the geyser only from solar...).

1 hour ago, frivan said:

Redundancy is a function of your essential loads and how long the sun doesn't shine.

Agreed - but one must decide on the "days of autonomy" that one would be happy with (or can afford). I have 2 x 10.65kWh batteries, and we can can "survive" for three nights and two days without sunshine if we work sparingly (like switching the geyser off on day 2). With a third string (that I'm planning to install within the next few months) we will have a comfortable full 3-day autonomy.

Good luck with your designs and installation - it's exiting times...

That makes sense - I do see the redundancy need for low/no production days and agree there is a balance to how much time we can survive on low to no generation but also balancing the budget.

I was more talking to the idea of having 2 batteries in the system to build redundancy if one were to fail at least the system then would not be completely out of battery.

Hi there and welcome to Powerforum! Great first post with solid details on your 15–20 kWh daily usage, 5.9 kW peak, north-facing unshaded roof, and R150k target. You're in a strong position for excellent energy independence in Joburg.Recommended Setup Optimised for Your Needs.

• Inverter: Solis LV Hybrid 8 kW (highly recommended) or 12 kW if you want extra headroom.

• Battery: Kynee 15.3 kWh or 2× for ~30 kWh total the price jump is often small and worth it for extra autonomy.

• Panels: 12–14 × 550–650 W Tier 1 bifacial (JA Solar, Trina, Longi with BC tech, or Canadian Solar) for a ~7–9 kW array. Your unshaded north-facing roof is perfect use multiple MPPTs e.g., 2 strings north + 1 east for maximum yield.

This setup should cover your modest usage comfortably on sunny days and during loadshedding, with room to expand.

Maximising Efficiency Tip: Slightly oversize the PV array and swap your geyser element to 2 kW. This lets excess daytime solar run the geyser far more effectively.

Total installed cost: Realistic R130k–R150k fully done cabling, DBs, CoC, etc.

Why Solis is the Superior Choice While many members recommend Sunsynk or Deye mainly because they’re very familiar with those products, the Solis LV Hybrid is far superior in almost every practical aspect for a residential install like yours:

• BloombergNEF Tier 1 manufacturer top global ranking with proven bankability, stronger reliability, and better support for banks/insurers/property value.

• Standard 10-year warranty on the LV 5/6/8 kW models.

• Advanced power blending similar to Victron seamlessly mixes PV, battery, and grid power.

• Generator integration on either utility or backup port with auto-start.

• AC coupling support with frequency shifting for easy future expansion.

• Impressive overload capability runs 200% load for 10 seconds.

• Ultra-fast 4 ms changeover time.

• Superior MPPTs support larger arrays, lower startup and production voltage, wider voltage range, and built-in Arc Fault Detection (AFD). If an arc is detected, the inverter automatically switches off the affected MPPT to prevent fires.

• Better compatibility with modern panels: Deye and Sunsynk have known limitations with larger capacity / higher current modules (maximum amps per string), which can damage their MPPTs. Many installers are not fully aware of this risk. Solis handles the latest high-power bifacial panels without issue.

Newer panels are almost all bifacial (some with BC tech like Longi), offering higher efficiency, easier cleaning and maintenance, and greater rigidity thanks to the double-glass configuration.

All of this comes at a noticeably better price point while delivering premium performance.

Battery Choice & RedundancyKynee 15.3 kWh (Chilwee Group) LFP chemistry with a true active smart BMS one of the few in SA with active balancing.

Decent quality batteries like the Kynee with active BMS are far less likely to fail than older or passive-BMS models. The active balancing keeps cells in perfect health, significantly reducing the risk of issues that could lead to failure.

That said, your point about redundancy is valid having two batteries does give you peace of mind: if one were to have a problem, the system would still run on the remaining battery instead of going completely dark. Many members go the 2×15.3 kWh route for exactly this reason, especially since the incremental cost is reasonable and you gain a lot more daily autonomy as well.

Active vs Passive BMS: Most Deye/Sunsynk-paired batteries use passive BMS bleed excess energy as heat slower and less efficient. Kynee’s active BMS transfers energy between cells for faster, cooler, more efficient balancing, better health, and longer lifespan.

Mixing batteries: Not recommended different sizes cause BMS issues, uneven cell/bank balancing, and potential problems.

Stick to identical units.Warranty/Support Edge: Kynee offers 48-hour swap-out turnaround a massive advantage over the long repair waits common with many other brands including Sunsynk/Deye setups

.Your Technical Questions Essential vs Non-Essential Loads
Non-essentials can still use excess solar during the day via CT control ideal for your geyser. They drop during loadshedding, while essentials stay on inverter + battery.Next Steps & Installers Prioritise PV GreenCard accredited installers experienced with Solis in the northern suburbs.

The Powerforum Store stocks Solis, Kynee, and the latest Tier 1 bifacial panels at competitive prices and can recommend reliable, trusted installers we work with regularly.

You’re welcome to contact [email protected] and ask for Steve or Wimpie they’ll be happy to put together a full package quote single or dual battery options and suggest suitable installers for your area.

Post your roof photos, latest bill, or any quotes here and we can fine-tune further.

This Solis + Kynee setup delivers Tier 1 quality, advanced safety features, active BMS benefits, fast support, and strong independence all within your budget.

Looking forward to helping you get this sorted! Any questions, just ask.

Thanks for this, I do have an initial quote from Wimpie for 10 panels but I guess it may make sense to up the panel count if possible - a couple of questions

If I go 12 - 14 panels, what would the strings look like 2x 5 string north and 1x 4 string east - would this be large enough or would I struggle on the start-up voltages?

On 12 panels at say 600w panels I have a 7.2kw potential - would this not be too low to be effective if I went on the 2x15kwh batteries?

On 2026/05/25 at 4:16 PM, Koch903 said:

Hi everyone,

Longtime lurker, first-time poster.

I’m based in Joburg and am starting to look seriously at installing a solar/battery backup system for our home. I’ve learned a huge amount from reading through this forum already, but I still have a few questions before pulling the trigger.

The goal is to build as much energy independence as possible without completely blowing the budget. Ideally, I’d like to keep the total installed cost under around R150k if possible.

We currently average somewhere between 15–20kWh per day, although that has only been monitored over roughly a month since we recently moved in, so I realise that may still change. I have been trying to monitor a bit more accurately with the Itron municipal panel installed and the max draw I have seen is just under 6kW(+- 5.8 - 5.9)

At the moment I’m thinking along the following lines:

• 10–12kW inverter (currently considering Sunsynk or Deye)

• 15–20kWh battery capacity (not sure which battery brands are considered best value/reliability)

• 10–12 x ~600W panels (again, unsure on best brands/specs)

A few technical questions:

1. My understanding is that most inverter setups separate “essential” and “non-essential” loads. If something like a geyser is connected to the non-essential side, does that mean it can still use solar power during the day but will never draw from the batteries? Or is the non-essential side always purely grid powered?

2. I often see people using batteries of identical sizes/capacities in parallel. Is there a technical reason for this? For example, is it a bad idea (or even possible) to combine something like a 15kWh battery with a 5kWh battery?

3. Any general thoughts on the proposed setup above would be greatly appreciated, especially whether it seems appropriately sized for our usage and which products/brands you’d recommend.

And lastly, not sure whether this is against forum rules, but if anyone has recommendations for reputable installers/providers servicing the northern suburbs of Joburg, I’d really appreciate it.

Thanks in advance.

Welcome to the forum, please make sure to buy from only reputable companies or deal with an installer that you can pay on completion.

The solar industry in South Africa is completely run over with scams.

4 hours ago, Koch903 said:

If I go 12 - 14 panels, what would the strings look like 2x 5 string north and 1x 4 string east - would this be large enough or would I struggle on the start-up voltages?

On 12 panels at say 600w panels I have a 7.2kw potential - would this not be too low to be effective if I went on the 2x15kwh batteries?

In my opinion, if you cannot afford more panels now, I would install 2 strings of 6-8 panels each with both strings facing north. If there is space for a 7th or 8th panel on one, or both of these strings, get your installer to allow for their addition with this installation (add the mounting rails now)... then it will be very easy for you to just add those panels later on if you discover that it is necessary. The same goes for your third string, allow for the trunking, cabling, isolators, surge arrestors, etc and have that all installed now, making things much simpler when you install the east string at a later stage.

Regarding your second question: That would depend on your power consumption and lifestyle. My wife and I have averaged about 17kWh used per day for so far in 2026, and my 20kWh batteries have only dropped below 70% SoC (thus used more than ~6kWh through the night) twice this year - with such a light night-time load the batteries are fully recharged (99-100% SoC) by 10:00 at the latest, with the 2kW geyser then heating between 10:00 and 14:30. My 14 x 575W panels easily handle these loads, plus normal living consumption (coffee, toast, cooking, ironing, etc.) at the same time, and can still also run either a 2kW heater, or the oven, between about 10:30 and 15:00 - but not both at the same time... If your "after dark" consumption if much higher (thus dropping your SoC to say 40%) then your daytime battery charging will take longer to fully recharge the batteries, which might limit your daytime usage of other high-consumption devices (such as a geyser or an oven) whilst the batteries are charging. Fortunately, if you have allowed for the installation of a third string on the east-facing roof, as I suggested above, it will be an easy and quick operation to install that third string if you find that the two north-facing strings cannot cope.

Edited May 28May 28 by HennieL
clarified overnight consumption abd not using heater and oven at the same time

21 hours ago, Koch903 said:

Thanks for this, I do have an initial quote from Wimpie for 10 panels but I guess it may make sense to up the panel count if possible - a couple of questions

If I go 12 - 14 panels, what would the strings look like 2x 5 string north and 1x 4 string east - would this be large enough or would I struggle on the start-up voltages?

On 12 panels at say 600w panels I have a 7.2kw potential - would this not be too low to be effective if I went on the 2x15kwh batteries?

Hello

So the beauty of the Solis Hybrids are their Low Production and Startup voltage on their MPPT's on the Pro Models this is very low and the Pro Models are also slightly cheaper than the Plus Models you are looking at 90V Startup and production meaning your 4 panel string will be fine.

Also on the battery capacity I have 7.3 KW PV and my battery is 38.5 KWH the extra capacity helps when its overcast and even if I run as low as 90% dod takes about a day and a half to reach 100% my average winter consumption is 20 KW per day so normally morning SOC sits at 73 % if I run the aircon for an hour or two at night (heat mode Cold Winters) it sits at 60% SOC I am fully off grid no utility backup or power.

I also run an electric geyser 6 fridges and freezers borehole pump circulation pumps CCTV 8 Cameras outside lights always on Air Fryer Electric Kettle and Microwave and obviously WIFI internet TV at night etc

So no the array will not be too little however it does depend on your consumption average but if it is within the 18 to 22 KWH margin then your battery will be able to fully recharge.

I hope this helps

Edited May 28May 28 by Powerforum Store

40 minutes ago, Powerforum Store said:

Hello

So the beauty of the Solis Hybrids are their Low Production and Startup voltage on their MPPT's on the Pro Models this is very low and the Pro Models are also slightly cheaper than the Plus Models you are looking at 90V Startup and production meaning your 4 panel string will be fine.

@Powerforum Store Can you please clarify the differences between the Solis "Pro" model and the "Plus" model. Your online shop website does not identify the two models that I could see, but based on your statement that the "Pro" model is slightly cheaper then the "Plus" model, I assume the 12kW single phase model S6-EH1P12K03-NV-YD-L with 10 year warranty selling at R34,672.50 is the "Pro" model, and the SOL-S6-EH1P12K-NV-YD-L with a 5 year warranty selling for R 35,075.00 is the "Plus" model? What's confusing is that both these models have the same data sheet (S6-EH1P(12-18)K03-NV-YD-L). Also, do both of these models have 3 MPPT's?

17 hours ago, HennieL said:

@Powerforum Store Can you please clarify the differences between the Solis "Pro" model and the "Plus" model. Your online shop website does not identify the two models that I could see, but based on your statement that the "Pro" model is slightly cheaper then the "Plus" model, I assume the 12kW single phase model S6-EH1P12K03-NV-YD-L with 10 year warranty selling at R34,672.50 is the "Pro" model, and the SOL-S6-EH1P12K-NV-YD-L with a 5 year warranty selling for R 35,075.00 is the "Plus" model? What's confusing is that both these models have the same data sheet (S6-EH1P(12-18)K03-NV-YD-L). Also, do both of these models have 3 MPPT's?

Hello Hennie

The Pro Models are the first line of S6 Hybrid inverters they do not have display screens on the inverter and use Bluetooth, Lan and WIFI via the Solis Cloud app for config and setup these are the 3.6, 5, 6 and 8 KW LV Models. All HV models have display screens. They also have the very wide range MPPT units that start producing at 90VDC and has a maximum voltage of 600VDC.

As an example the 6 KW Unit for the pro model can produce 9.6 KW PV on its two MPPT's

They all have an IP66 Rating and has all the feature sets like AFCI 200% Load for 10 Seconds 4ms changeover AC Coupling Generator integration on AUX port or grid with signal and auto start and they truly blend power like Victron and a lot more.

They all come with a standard 10 year warranty.

The newer Solis Plus Models have large display screens on the front of the inverters for the 5, 6, and 8 KW Solis introduced the screens due to user demand they still have Bluetooth Lan and WIFI.

They also have all the feature sets like the older model with some extras like the large display their MPPT's wake up at 89VDC and produce at 90VDC but is limited to 500VDC however their PV capacity is 200% of the inverter rating so the 6 KW Unit can produce 12KW from its two MPPT's

These models all come standard with a 10 year Warranty 5, 6 and 8 KW units however the larger LV models 12 14 16 KW units have a standard 5 Year warranty with a warranty extension option up to 25 years (to be confirmed) the 10 year extension is available some distributors sell these models with the extended 10 year warranty included but there will be a marked price difference so be aware of that when buying the larger models this also applies to the HV Models standard 5 Year warranty with some Distributors selling 10 year warranty models.

We try to sell mainly 10 year warranty models we constantly have to check the prices to ensure the model we are selling is 10 Year if not we will let the buyer decide if he wants a 5 Year or 10 Year warranty machine.

Important point on the Solis Warranty is that its a Swap out warranty and NOT a repair warranty. Their turnaround time is fast and efficient with no unnecessary delays.

As a Comparison Currently have a client with a Sunsynk inverter where the inverter was sent back for warranty repair its now 1 month and 2 weeks and we still have no feedback on if the inverter will be repaired under warranty or not needless to say the client is freaking out.

All of the Solis inverters are NRS097 Approved and Solis Brand is a Tier 1 Inverter brand Sunsynk / Deye for example are Tier 2 Inverter brands.

We just recently sold a system to a client that included 2 x 6 KW solis pro Inverters 24 x 460 Watt JA Solar Bi Facial panels with roof mountings and 2 x 15.3 KW Active BMS batteries and all the cable and required accessories for around R113 000 EX Vat and that included delivery to his doorstep. In my opinion that is a very robust system at a very reasonable price.

18 minutes ago, Powerforum Store said:

We just recently sold a system to a client that included 2 x 6 KW solis pro Inverters 24 x 460 Watt JA Solar Bi Facial panels with roof mountings and 2 x 15.3 KW Active BMS batteries and all the cable and required accessories for around R113 000 EX Vat and that included delivery to his doorstep. In my opinion that is a very robust system at a very reasonable price.

This is very close to the type of setup I was referring to in a previous post. Sorry, have to repeat this: it's a great setup for someone who needs more autonomy from the grid. But if you've got low usage of 15-20kWh daily, and typically under 6kW of peak power, then you could cut this system basically in half, I guess for around half the price, and still have a system that will meet your power needs 95% of the time (okay, I'm making that number up, but you get the point), as long as you stay grid-connected. And if you then still want to go more off-grid, then the logical upgrade path will be to buy the other half of the system.

On 2026/05/26 at 11:02 AM, GreenFields said:

Or else go with a 6kW Solis hybrid at the start, with just one 15kWh battery and 8x600W panels on just one MPPT, and keep the non-essentials on the grid side but powered from the inverter too. That's for a more cost-effective more grid-tied start-up that you could scale up by doubling everything up. Even if you don't, it should already go a long way towards covering the 15-20kWh daily usage with 6kW peak usage on most days. Your usage is not actually that much that a smaller system couldn't handle most of it even if it's sometimes a squeeze. How often is the grid out in your area, though? I'd be leaning towards the 12kW inverter and doubling from the start if grid-independence is the main immediate concern.

Thanks to everyone for the input so far. I have now received 9 quotes across 5 (what I believe to be) credible installers. I am trying to decide between the following two options:

• Sungrow 10kw system - Sungrow 10kw inverter (4 mppts), Sungrow 10kwh battery and 10 * 620w panels - R129 979.90 (with the option to add an extra 5kwh battery for R19 500)

• Sunsynk/Dyness system - Sunsynk 12kw inverter (3 mppts), Dyness 16kwh battery and 12*600w panels - R144 050.07

I am leaning towards the Sungrow system as it is (1) cheaper and (2) the battery/system is fully warrantied with 100% DoD - I am slightly worried that 10kwh battery is not enough, but the installer has also told me that the way the Sungrow system works, adding additional batteries is very simple in the future. On the other hand, the Sunsynk system does have slightly more inverter capacity, solar genetration and battery capacity, but I am not sure that is worth the additional ~10% in spend.

Edit: The second thing I am considering is whether I convert to a prepaid meter before doing the install to limit connection costs, however I am confused about the rules, regulation and enforcement of this from the COJ.

Edited May 29May 29 by Koch903

1 hour ago, Koch903 said:

Thanks to everyone for the input so far. I have now received 9 quotes across 5 (what I believe to be) credible installers. I am trying to decide between the following two options:

• Sungrow 10kw system - Sungrow 10kw inverter (4 mppts), Sungrow 10kwh battery and 10 * 620w panels - R129 979.90 (with the option to add an extra 5kwh battery for R19 500)

• Sunsynk/Dyness system - Sunsynk 12kw inverter (3 mppts), Dyness 16kwh battery and 12*600w panels - R144 050.07

I am leaning towards the Sungrow system as it is (1) cheaper and (2) the battery/system is fully warrantied with 100% DoD - I am slightly worried that 10kwh battery is not enough, but the installer has also told me that the way the Sungrow system works, adding additional batteries is very simple in the future. On the other hand, the Sunsynk system does have slightly more inverter capacity, solar genetration and battery capacity, but I am not sure that is worth the additional ~10% in spend.

Edit: The second thing I am considering is whether I convert to a prepaid meter before doing the install to limit connection costs, however I am confused about the rules, regulation and enforcement of this from the COJ.

You can't convert to Prepaid anymore. Solar or not.

6 hours ago, Koch903 said:

I am leaning towards the Sungrow system as it is (1) cheaper and (2) the battery/system is fully warrantied with 100% DoD

I am always very skeptical about cheap systems that promise things like "100% DoD", even if it is "warranted". In my opinion, and taking into account that one would expect an acceptable service for a period of 12-15 years, one should not settle for the cheapest install "just because it is the cheapest". Have you looked at the actual warranty requirements (specifications) from the manufacturer? Would daily discharging down to 100% DoD still give the "warranted" service life of industry standard 6000 cycles? What if the operating temperature was (say) 30 degrees, or even 40 degrees, as is common for many places in South Africa... What if your charging and/or discharging rate was (say) 0.5C or 1.0C (here, "C" is not temperature, but current ratio, with 1.0C being your battery's rated nominal current capacity (~100A for a 5kWh battery...)?

The old Afrikaans saying "Goedkoop koop is duur koop" is very true when it comes to solar... have a look at this recent thread: https://powerforum.co.za/topic/34086-lfp-and-other-lithium-facts/

9 hours ago, HennieL said:

"100% DoD"

A cheap system could set their 0% where others call it 20%. But then you would see poor energy per weight figures.

Sungrow is a reputable player in the grid scale environment, I would buy their equipment.

16 hours ago, Koch903 said:

Thanks to everyone for the input so far. I have now received 9 quotes across 5 (what I believe to be) credible installers. I am trying to decide between the following two options:

• Sungrow 10kw system - Sungrow 10kw inverter (4 mppts), Sungrow 10kwh battery and 10 * 620w panels - R129 979.90 (with the option to add an extra 5kwh battery for R19 500)

• Sunsynk/Dyness system - Sunsynk 12kw inverter (3 mppts), Dyness 16kwh battery and 12*600w panels - R144 050.07

I am leaning towards the Sungrow system as it is (1) cheaper and (2) the battery/system is fully warrantied with 100% DoD - I am slightly worried that 10kwh battery is not enough, but the installer has also told me that the way the Sungrow system works, adding additional batteries is very simple in the future. On the other hand, the Sunsynk system does have slightly more inverter capacity, solar genetration and battery capacity, but I am not sure that is worth the additional ~10% in spend.

Edit: The second thing I am considering is whether I convert to a prepaid meter before doing the install to limit connection costs, however I am confused about the rules, regulation and enforcement of this from the COJ.

If you were to add another 5kwh battery to the sungrow system it would be roughly R150k (so then both systems would have the same amount of usable energy as the dyness has a 95% DOD), which would make it R6000 more expensive. You would also need to account for the two additional panels on the other system, add these to the sungrow system and you are looking at roughly R156k.

I am not sure about Sunsynk/Dyness combo but i know that with a deye/dyness combo you get a 10 year warranty on the inverter and battery.

On 2026/05/29 at 8:57 AM, Powerforum Store said:

The Pro Models are the first line of S6 Hybrid inverters they do not have display screens on the inverter and use Bluetooth, Lan and WIFI via the Solis Cloud app for config and setup these are the 3.6, 5, 6 and 8 KW LV Models. All HV models have display screens. They also have the very wide range MPPT units that start producing at 90VDC and has a maximum voltage of 600VDC.

The newer Solis Plus Models have large display screens on the front of the inverters for the 5, 6, and 8 KW Solis introduced the screens due to user demand they still have Bluetooth Lan and WIFI.

They also have all the feature sets like the older model with some extras like the large display their MPPT's wake up at 89VDC and produce at 90VDC but is limited to 500VDC however their PV capacity is 200% of the inverter rating so the 6 KW Unit can produce 12KW from its two MPPT's

A belated Thank You to @Powerforum Store This clarifies it well

On 2026/05/29 at 8:57 AM, Powerforum Store said:

We just recently sold a system to a client that included 2 x 6 KW solis pro Inverters 24 x 460 Watt JA Solar Bi Facial panels with roof mountings and 2 x 15.3 KW Active BMS batteries and all the cable and required accessories for around R113 000 EX Vat and that included delivery to his doorstep. In my opinion that is a very robust system at a very reasonable price.

This is a very good price. Given that installation costs for the various systems should be fairly similar, it would be interesting to compare purchase price of the three systems (Solis 2x6kW vs Sungrow 10kW vs Sunsynk 12kW), especially when also comparing the variance in battery and PV capacity of the three systems (2 x 15.3kWh vs 1 x 10kWh vs 1 x 16kWh for the batteries and 11.04kWp vs 6.2kWp vs 7.2kWp for the PV)... That's a "no brainer" for me.