Deon in ZA

My apologies, I was busy at the time, I didn't have the capacity to respond in full.
Axpert inverters typically work well if all you want is a UPS, keeping essential loads going during a power failure or load-shedding utility. That said, there are losses in efficiency with any inverter, charging batteries from AC (AC -->DC conversion), storing the DC charge (standing losses), and then converting it all back from DC to usable AC again. These efficiency losses means that It becomes expensive to just keep the lights on.
So you add some solar panels, thinking that it would be great to offset some of these losses using sun power. And it is, solar panels charge the batteries, and but when they are charged, they just sit there in the sun. So you decide that you want to use them directly to service loads, and they can, but the problem with most axperts is that they either use 100% Eskom power, or 100% battery power or 100% solar power, there's no in-between. This means that if you have a 5K Axpert inverter with panels capable  generating say 2500W DC, and your load is 2000W, all is good, the inverter will convert and use solar power to power loads. The problem is when a cloud happens along, and solar generation drops to 1500W. The axpert-type inverter will switch 100% from solar to grid, and if not grid, 100% to battery. This is true for most axpert-type inverters, although I have heard of some that can do limited "blending" of sources. The Sunsynk, by contrast, will blend any source depending on how it is set up. In the above scenario, it will still use the 1500W from the panels, but supplement it with 500W of power from the grid, battery, aux, genny or wind turbine. So it is far more efficient.
Another difference is that it is a true bi-directional hybrid inverter ( Sunsynk uses the term "Super Hybrid Parity Inverter"). The Grid and Aux input is bi directional in the sense that it operates as both an input and an output. So it can draw current from the grid or aux, and it can send current back to the grid / aux. It can also limit the load of the current flowing in either direction too, to a pre-determined wattage. This significant because, due to budgetary contraints, most homeowners cannot afford to put in a 20kW inverter, and so they split their db into essential and non-essential loads. Essential loads are usually quite light, and allow homeowners to reduce the size of the inverter to say 5kW. The non-essential loads are usually big current hogs (like water heating and pumping), and they are placed before the inverter, on the grid side, effectively being served directly by the grid before grid power even reaches the inverter. This also means that they are down when the grid power goes, but hot water is quite stable and doesn't change its temperature in four hours, and the pool won't go green immediately if there isn't any pump working, so this kind of works well from a functionality perspective. The problem with this is that it does not result in much efficiency gains or electricity savings, because the biggest current hogs are also the ones that are still serviced by the grid (when it is there). So homeowners either have to buy a bigger axpert type inverter, or get a smaller hot water installation, or change the element to a smaller one, or get a soft starter for the pool pump, and/or shift the load to the essentials side. The Sunsynk hybrid can safely export power to the grid side though, using a Current Transformer or CT coil to measure directional load (when the grid is up).
So if you have a 4000W hot water heater element, it can still be on the grid or non-essentials side, but the Sunsynk can pump 4000W of excess solar to it. The CT coil measures the power and the inverter will reduce power when too much power is detected going to the grid. Even better, if the Sunsynk inverter only has 2000W of excess solar, the element will receive the other 200W from the grid. So it is efficient. The same with the Aux port, it is bi-directional, so it can be configured to take a genny input, or act as an output or "Smart Load" as Sunsynk calls it, and you can dump excess solar power towards it.
Here is a video which explains it:
Also important is battery support, the Sunsynk manual lists over 3 pages of batteries that it supports, most with CAN or RS485 communications.
Another difference is the wide range of capacities that it supports. In addition to the ability for it to parallel (up to 16 inverters), it comes in 3.6K, 5.5k, 8.8K, and a whopping 16K for single phase installs, and there are 12 and 50K 3phase units available. Not even Victron makes such a wide range of self-contained units, their biggest is 5K.
Pricing is a little more expensive than axpert-types, but it is nowhere near the pricing of Victron, which is a whole lot more.
This probably covers the most pertinent differences between the majority of Axpert and Sunsynk Hybrid inverters, but it is certainly not all, and other forumites are welcome to supplement it with their favourite ones. There are many others, from its easy to use interface, to the warranty and support in South Africa, that are equally important. It's simply in a different league.
Please note that I am not affiliated to Sunsynk in any way, I am just an enthusiastic owner who discovered this brilliant piece of kit under two years ago. 
                 
   
 

Introduction
What is presented here is my experience with solar over the past 2+ years.  I hope this write up will be of value to readers and assist with their journey, its become a hobby.  Feel free to comment.
The section on Payback represents a situation faced by most homeowners and reflects an approach which I thought appropriate.  Our unit cost is relatively low, and the same applies to savings.  Data on the number of hours without power, cost of generating power using a generator is not readily available. There is recognition of increased cost of power during an outage, but the approach is debateable.  I’ve steered away from opportunity costs.
 
Objective
1.       To provide power during load shedding and frequent extended outages experienced due to unreliable and worsening municipal electrical infrastructure (also not keen on using a generator, bit of a closet greenie).
2.       Provide power to keep lights, fridge freezer, router, office, (desk top PC, screen, printers) as well as DSTV decoders and TV’s going.
3.       Eliminate (or reduce) frustration experienced every time power goes off.
4.       Recoup investment in solar in as short a time frame as possible and reduce reliance on ESKOM.
 
The system
·         Goodwe 5048D-ES 4.6 (current DOD while on grid 5%, off grid 90%)
·         17 x 365w Canadian solar panels = 6205w (8 facing North, 9 facing North West) at 11 degrees from horizontal
·         2 x 3.5kw Pylontech batteries current SOH 99% (changed from 100 to 99% shortly after 18Dec 2021 after 23.5 months of use).
·         Installed Jan 2020.
Photos of installation in separate post
General information on electrical set up
·         Household 4 adults, residential and home office.
·          750w heat pump, water is heated to 42 degrees, no cold water used when we shower.  1 degree increase in water temp takes 6 min. Starting water temperature in summer about 26 degrees, winter about 20 degrees.  Heat pump needs to be started a couple of hours before planned shower.
·         750w pool pump used for 2.5 hours per day from Oct to March.
·         Replaced electric hob with gas.
·         Replaced 50-amp municipal CB with 40-amp CB.
·         Due to extent of power failures all plugs, lights pumps are run through the inverter, only oven directly connected to municipal supply. 
·         The inverter capacity is 20 amps + 10 amps for 10 seconds before it trips.
·         Tripping of the inverter can be avoided by using 2 or less appliances at the same time, especially when the dishwasher or washing machine (max power use while heating water of 2400w) is on.  Training ongoing, it is easy to forget…
·         Normal background use of lights, fridge freezer, PC etc about 500 to 600w, this can be reduced to 350w in extreme cases if outside lights are turned off as well as PC and screen.
·         Power is sold and bought at the same rate (municipality under administration).
·         Only 40% of PV is used with current set up (self-use), rest provided to grid.
·         Electricity meter read at month end and provided to municipality.  They use the information!
Cost in December 2019 + fixes to DB later

 
Monthly power produced and consumed based on data from inverter and meter readings

Yellow = 5 months with lowest PV produced and highest meter reading.  Green = 5 months with best PV produced and lowest meter reading.
I suspect actual consumption is higher and saving would be higher than shown.  The Goodwe does not keep track of power supplied from the battery (both on and off grid).
Summary data (gradual improvement)

 
Payback
The variables used to calculate the original payback period changed.  The solar system produced less power than anticipated (635w vs 900w) and cost more.  Both would increase the payback period.
At the moment payback will be about 10 years based on the following assumptions.
·         Continue to sell to back power at same rate as purchased
·         Eskom increases for 2022 = 9.61% and from 2023 will be at least 6% per annum
·         No major breakages
·         At least 10 hours of monthly outages that equals 20 kWh at, at least 4 times the going rate per kW.  For March 2022, 10 hours x 2 kw per hour @ R1.51 x 4 per kW = R121/month.  I believe this assumption is conservative.  My calculations show kW cost from a generator is far greater than R10 per kW
·         No interest added to original investment of R150k.
Should increases be 8% per annum, power outages double and cost per kW increase from 4 to 8 times the going rate (see example above), payback will shorten to 7.5 years (so 5.5 years more to go).
SARS allows a proportional depreciation over 3 years for a home office, effectively reducing the original investment by about R25k.  This will reduce the payback period by at least another year from 7.5 years to 6.5 years.
Perhaps financially not the best investment decision (but better than Steinhoff) and to date happy with the outcome.
 
Lessons learnt, observations
·         Educate yourself about solar, speak to many people that have installed solar, join, read, and ask question on powerforum!
·         Understand what your objective is and what you want to achieve.
·         Get at least 3 quotes, make sure you deal with a reputable company and that the inverter has been “accepted” in the larger metropolitan areas of the country and that the batteries are compatible and supported by the inverter.
·         Give preference to systems that allow incremental additions e.g., adding extra battery capacity or extra inverter. I can’t do the latter.
·         The company should provide information on expected production, make sure they disclose the variables on which it is based and expected production throughout the year. If they don’t, move on.  Only one of the 3 companies that quoted provided this information.  Some also appear to be stuck on a single range of products.
·         Make sure to get a COC for the solar installation and the DB. Useful for insurance in case there is a problem (lightning, wind damage, surges)
·         I obtained theoretical production values from the website below for my location, and while the monthly values varied a lot, I’m at 96% of the predicted production of 16 513w for the 25 month period https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html
·         Somehow everyone, forgot that parts of the country experience cloudy/rainy conditions and that the 30kwH per day or 900 kwh per month is probably only relevant in the desert.  Actual production of the “900 kw system” turned out to be 635kWh per month.  Don’t like me accept information at face value.  The screenprint below is an example of the type of information out there, ready to confuse the novice.…

·         Be aware that system losses can be between 14 to 25%.  Reasons include converting from DC to AC, temperature, inverter efficiency, etc.  For my system and location predicted losses were expected to be 25.6%. 
·         Bear in mind that your panel mounting areas largely dictate production.  In my location optimal angle = 35 degrees, however the roof angle is only 11 degrees.  Production in Gauteng will be better as solar radiation is higher.
·         Shop around, one supplier is seldom cheapest on all the major items (panels, inverter, mounting structures, batteries).
·         Include in the quote to fix, or have your DB checked beforehand to prevent surprises. I did not and probably paid R8+k extra.
·         Understand what items you want on the backup (battery) circuit.  In my case initially lights, fridge, freezer, TV, decoder, router.  Had it changed later to include all plugs, heat pump and pool pump as with frequent outages while the sun was shining, we were unable to consume the power being produced. Obviously cost extra.
·         Ensure there is good airflow between the roof and the panels, heat reduces production of power.
·         Plan to be able to clean the panels by leaving a walkway between sets, dust, grime, birds can reduce PV production by 5%.  At 11 degrees angle my panels don’t self-clean!  I use a soft broom with a plastic extension to reach 2 meters and a hose pipe.  There are small yellowish sticky deposits that even resist a high-pressure cleaner.
·         I can only communicate with the inverter via wifi. I installed an UPS to power the ONT box and router in case there is a need to change settings on the inverter.
·         Understand the limitations of your inverter, I am unable to use a generator with the Goodwe and hence unable to charge batteries in periods of ongoing power failure and consecutive cloudy/rainy days.
·         Specify that a bright LED be added where it is easily visible, (probably in the kitchen to indicate a power outage). This to prevent use/waste of battery power when there is no sun. Backup systems are so efficient you are often not aware that loadshedding or a power outage is occuring.
·         If in future unable to feed back into grid I will have to increase battery capacity and the payback period will increase.
·         Don’t wait, invest now.
22 March 2022

You can e-mail Solarman client service ([email protected]) and ask them to increase the data logging frequency, and just give them the data logger serial number.  For 2 separate inverters I have e-mailed them and asked the data logging frequency to be increased to log data every 1 minute, and they have changed it to log every 2 minutes, so maybe 2 minutes is the best they can do.  But a data point every 2 minutes is still much better than only every 5 or 6 minutes like the default.  It does not shorten the lag between an event happening and being able to see it on the app, but if you pull the historic data on the app or website it will be in more granular detail due to the increased number of data points.

Instantaneous (no login), real-time data (way more than PV or SEMS gives you, extractable to file, history of performance and parameters, a system tray icon that gives you SOC%, a friendly dev. The list goes on and on! Worth a try.

Super easy Solarman data logger integration with HA.
https://github.com/StephanJoubert/home_assistant_solarman
Edit: Just to clarify, I'm not the author. The author is quite active and responds to queries within a day or so.

Hi all,
I listed some of the steps to get remote control working on Solarman Smart and Solarman Business in my installation thread, but seeing South African installers are generally unable or unwilling to assist it is probably worth highlighting it here under a separate heading.  This is the process and works as of December 2021 - Solarman seems to have little regard for change control so it may not work next year, next week, or later today.
Its been quite an ordeal, but I got it working in the end. As I remember the steps are: 
Forget about Google Playstore - the versions on there are outdated and do not support remote control (or maybe my users had not been authorised at the time) so better to get the latest versions from the Solarman website. Download the correct version of Solarman Smart from the Solarman website by scanning the QR code (currently V1.5.17) Enable unknown sources on phone (I used "My Files") Sideload apk file If you want to use Solarman Business (worth it for much better Web interface and more intuitive remote control function alone) you need to do the same with this app (Latest version 1.6.14).  Contact Deye support [email protected].  This is where I got the email from Jessica asking if we could do Whatsapp or Wechat instead (QR codes below). When sending instant messages be considerate about China being 6 hours ahead of us - better done in the morning SA Time. She has to authorise your Solarman Smart user to be able to make changes.  It may be easier to test this on the web app than on the phone. Note: for some reason the web interfaces work on Edge but not on Chrome.  When done you will see a "Remote Control" button on the Device tab in the app, or and away you go. The Work Mode settings we are after is under System Work Mode-3(Selling Mode Time), System Work Mode-6(Selling Mode Time %) and System Work Mode-2(Selling Mode Time charge) On the web interface, go to Device > Operation > More > Remote Control for the same.  Then Deye support (Jessica) must also authorise your Solarman Business account so it is visible from the Smart app. To link the Buisness account, there is no need to create a plant an link the logger (it wont work in any case, as it already belangs to your Smart user).  You have to link it from the Solarman Smart app. Go to Plant, click on 3 dots, Authorisations, then search for Buisness account and add it.  If the Business account does not show up, go back to Step 11 above. In Business app, your user must then be authorised as Super Admin for the Smart account.   If this all sounds a bit confusing, it is! Good luck!
  
 

Here are my notes on the SunSynk 8k on the v7 Dec 2021 manual:
https://www.sunsynk.org/manuals

These notes are for a
SynSynk 8k PV Lithium battery Zero Export (self consumption) no generator all loads on "Critical" If you have no PV or no Lithium or are exporting, then these notes are not for you.

My use case is as follows:
During day, use solar to run house and charge the lithium battery At night, use battery until 20% then use grid At night, if no grid (load shedding), use further 10% of battery then shutdown. At night, if grid returns, charge battery to 20% First set the Lithium Battery up as per manual section 5.13 Setting Up a Lithium Battery
Note that the charge / discharge Amps in image below is at 48V.
The charge / discharge Amps in the image needs to be below the "C" rating of your battery bank.
This needs to be below the "C" rating of your battery bank.

If you have 4 batteries in parallel, the charge/discharge current (Amps) increases by 4.
I have 6.4kWp of PV and 4x100Ah 1C batteries.
I use 150A at 48V = 7200W (150A/4=37.5A) which is less than each AM2 battery Amp and "C" rating.
Initially I had an 85A charge setting, and this limited the PV to battery charge to about 4000W. 
After changing to 150A (48V) the batteries charge at ~6kW from the PV or ~1.5kW into each battery (at PV peak period).

It is highly recommended to connect the BMS to the inverter via a suitable CANbus or RS485 Modbus cable.
This allows the BMS to accurately control the charge from the inverter.
Confirm the communications is working via LI-BMS, you should see something like the left panel above.
If you get the screen on the right (just numbers), then the communications is not working.
Try updating the Inverter / battery firmware.
Support for new batteries is being added to the SunSynk firmware continuously.
The Dec 2021 Installer Manual has 43 different Lithium batteries listed.

--
Second set the Charge Amps and Tick Grid Charge as per manual section "5.11 Generator and Battery Page"
I use 60A setting which at 48V is 2880W

I have a relay that bonds neutral/earth connected to earth spikes when there is no grid.
See https://www.sunsynk.org/post/automatic-neutral-earth-bond
--
Third set the Shutdown % as per section "5.12 Battery Discharge Page"
I use shutdown 10% for a lithium battery - remember 10% is only if there is no grid and no solar (load shedding at night)
Normally the inverter will discharge the battery to the SOC/V (20%) setting in System Work Mode 1 below, then switch to grid.
The inverter will restart when 15% SoC reached (charged from 10%)


--

Fourth is System Mode - these settings are confusing as they have different rolls see Section "5.14 Program Charge / Discharge Times"
Charge / Discharge Times are designed for "Time-of-Use" functionality and grid export.
The idea behind of TOU is to load shift from peak to off-peak and export/use battery during peak and charge during off peak.
I don't use TOU or export, but these settings are required to ensure the inverter works as I want.
Since I don't do TOU, I've used the same settings for all the periods - 20% SoC & Grid Charge ticked.

I could only get the inverter to work as I expected when I ticked "Use Timer" - else it seem to work like a UPS.
I set my SOC/V to 20% and ticked "Grid" [Charge] as per image above.
Grid Charge is only dune under specific circumstances from 10% (Shutdown) to 20% (SOC/V) and is not normally used.
See "Grid Returns" below for effect of Grid Charge tick.
Note: I don't have anything on the Grid Side or Aux (Gen) Load - I do have a CT coil on the Grid side.

How it works with the above settings

Day Operation
The inverter will use Solar to power the Loads and excess to charge the battery to 100%
Once the battery reaches 100% about 11:30am, the excess is not used as I have zero export ticked.

Night Operation (or no sun) & grid available
Battery above 20%, the inverter will use the battery to power the load (note I don't have anything on the Grid side or Aux side)
Battery at 20%, the inverter will use the grid to power the load.
The battery will drain from 100% to 20% and stop and switch to grid.
The battery will remain at 20% waiting for Solar.
There will always be a 10% reserve in the event of no grid (see "No Grid" below).

No Grid (Load Shedding) at night
The inverter will use the battery from 100% to 20% then to 10% to power the load.
Battery at 10%, the inverter will shutdown.

Grid Returns (after Load Shedding) at night
IF you have "Grid" charge ticked AND Battery < 20% THEN
   The inverter will use grid to charge to 20% and stop charging the battery at 20%.
END IF
Once Solar returns, Solar will to charge the battery.
Note: Battery will hardly ever go below 20%. You need to be at 20% first when load shedding happens.

EDIT1:
One last tip - if LI-BMS is not working, ensure your inverter firmware is current as new battery support is being added all the time:
Nov 2021 Installer Manual had 28 Lithium batteries listed
Dec 2021 Installer Manual has 43 Lithium batteries listed

I found the below video on the Deye to be of some help in explaining TOU
Use pause/slow motion to see the animations.
https://youtu.be/79IUkH3tPQ8

EDIT2:
Clarity on Amp and "C" for battery bank.
EDIT3:
Clarity on the "Grid Tick" in Work Mode 1

And the windings are purrrrrfect.
 

What I did, I installed a relay, this one (https://hager.com/uk/products/h/epn525-latching-relay-2nc2no-230v), the two NO contacts are wired to my stove and Geyser. Then one N/C contact is wired to pilot light. The relay is mounted in my DB and the pilot light is below the DB. The Coil of the relay is wired directly to my incoming supply, grid/Eskom. When grid drops, the relay switch off and disconnect the stove and geyser so that they can not run from batteries and the pilot light gets switched ON to indicate that there is no grid supply. When you are in the kitchen, you will automatically see that there is loadshedding when the clock on the oven is OFF. So no one is allowed to use the kettle, microwave or dishwasher if there is no sun 

Hi AlexCape
Did found the problem and indeed it is few components that got damage. 
Battery switching power supply circuit diodes got damage.
Upload full repair manual of the 4 and 5kW unit.
 Copy_of_PIP-HS_MS_4-5KVA_new_Service_manual_201506A.pdf

I have a Goodwe, BUT if i had a do over I'd go Sunsync...

I built my home made battery charger to help my people that work at my house. I gave them each a 7AH battery and a china mall R35 LED light. I also gave them a LPG gas single cooker with bottle.Bring back the battery and I give you a charged one. I bought a number of these batteries and solar charge them. The cost was around R240 and R35. Its changed their life. No more paraffin.Good light for at least a week or two. Now imagine Eskom had a few of these power points. You bring me a 7AH and I give you a charged one for say R5.00. And I charge it with solar. You will change the life of 10 Million people, Instead they squandered Billions on cars, houses, overseas holidays etc etc. R275 to change a persons life??? 

2x Victron MPII, 6x US3000C, 3x Victron 250/85 MPPT, Cerbo & GX Touch, Panel meters monitoring PV string current & voltage, ICC & Pi monitoring individual batteries.
Added a circuit to switch in additional geyser to utilize excess solar with Cerbo generator start function. 


 



 

 

I was also threatened. Harassed. Abused. And threatened again. I played totally idiotic and when the chief engineer of SSEG called me and asked who installed my systems I said I did and asked why.
He asked if I had the qualifications and documents and I said no.
Then he threatened to take me to court. Only then did I tell him I am a mechanical engineer (retired) with years of expertise, and have decades of electronics design experience.
Took his email address and mailed him the CoC. That made him shut up.
About 6 weeks later I received the approval letter.
I hate government employees and politicians.

@FixAMess that's not why. The instantaneous data in Watts sent and extracted from the batteries, the Goodwe firmware informs them and sends them to the SEMS PORTAL, they simply have not designed the accumulators, that is, on the server side, the integration of the values sent in time to obtain kWh discharged or charged in batteries. In other words, it is a problem with the Goodwe software on the SEMS PORTAL and its API.
The new option of the Comparative Statistics of this software, tries to solve the lack of Goodwe.
Goodwe is a Plug and Play inverter, neither its firmware nor SEMS PORTAL software is intended for intermediate or advanced users.
And most users are comfortable that way.
One of the objectives of the development of this program is precisely to be able to know exactly what the system is doing and why it is doing it the way it does every second and little by little to develop other characteristics and capabilities far beyond the SEMS PORTAL. .

Version 3.0 in download area.
Regards !

This is a most AWESOME program. I can now make sense of my PV and inverter as a solar system.
Cef, THANK YOU for your time and effort, you are a star, your work, effort and dedication is highly appreciated.
Barry

And the second half is done.
The two 1/2 sections of one blade is done and matches very well.
Final trim and then to glue them together that I will do tomorrow. 

The two sections/flanges works very well far better that what I expected and if I want to do fiber glass blade then its ready to start the manufacturing.

I recon with the infusion process the accuracy of the usage of resin will be far better and I will definitely use less I recon a blade with wood mounting will cost +/- R 550 or R 1650 for a set of three carbon fiber blades.
When done I recon I will push for 4 or 5 meter blades. Its easy now that I understand the process and easy to get more done.
🤩  never expected this.
 


 
This is the top part of the second 1/2.  Very chuffed with it.

Wood prop & FG result next to each other.
Now I can determine the cost for a blade.

Resine            400G   R 220
Hardener        120G   R   70
Carbon Fiber             R 330 
Total                           R 620

Thus 3 blades R 1860.  At this cost I will now design a aluminum mounting system which I can use to turn the blade.

With the mold working well the two parts taking time is the cut of the carbon fiber that must be done at a greater accuracy and then the drying time in this weather is +/- 5 hours.
If one chooses to use wood to mount the blade then the extra cost for that will be one 3M 40 x 40 pine.  The cost R46

Considered the quote was R22 000 for 3 blades.

Now the manufacturing process of the blades I would consider done and the total build will start.

If you feel intimidated, go ahead and comply.
I am just saying my stance would be, unless it's a law, they can huff'n puff and then go swivel.

Very good feedback from ThatGuy, but also let me add one extra point
Your planned system is not static and both your requirements and the possible solution to those requirements will change.
I started out last year March with my main system, consisting of a Goodwe 4.6 with four 2.4 Pylontechs.
Few months later I moved both geysers over to evacuated tubes, to remove them off Eskom or my batteries at night.
Few months later I also changed the hob to gas and added two more 3.6 Pylons, to take me completely off Eskom at night, which was not part of the original plan.
My usage stats below. The May 2020 usage was a mess, as I was getting used to the system and switched back to Eskom on geyser usage and had much higher loads.
Then, my current usage, with better planning, more family education and changed usage patterns. Very little Eskom usage, mainly to sync the inverter.

Looks like you've done all your calculations. 
Your usage is similar to mine with the only difference that I have 3 aircons that run most days in summer. I also have 200l evacuated tubes and 4kw geyser element that switches on till 4pm from solar so kids can shower in the evening and again at 5am for the adults to shower in the morning. 
Your system should be paid for after 8 to 9 years. 
My setup cost me in total about R240k. Return on investment however did not feature as one of my main considerations when I decided to go solar. Reliable electricity was more important to me. Monthly savings from not paying CoCT for electricity I put away for future upgrades and maintenance cost. It's been running for nine months with no maintenance so far and only used some of the savings to add an additional battery and more panels. Future savings will go towards adding more batteries and possibly a wind turbine to get me some electricity when the sun is not shining. 
I could have taken the cash and invested it or basically prepay my electricity cost for the next 15 years by going solar. I decided to go with the latter. Even my water is off grid so I'm only paying CoCT for rates and refuse. Zero water or electricity charges. Water savings alone for the last 3 years is over R80k (initial cost of under R10k and only one pump replacement last year) with electricity savings currently at R28k after 286 running days. My average CoCT tariff is ±R2.50/kWh with a 13.5% increase expected in June. 
I was done with paying for corruption, incompetence, and subsidising free loaders through my electricity usage. The people going solar are the ones actually paying their monthly bills so the situation is just going to get worse for Eskom and municipalities. Every cent you pay goes towards propping up their failed system. If you have the funds and space for solar, you should go ahead. 

Interesting story - most of you already know this, but I was dumb struck by the magnitude of the effect...
 
We had an array of 7 panels in series (360Wp each), running just over a year.
Yesterday finally installed an 8th panel we'd provisioned for - expecting a 14% increase in yield.
Monitoring the PV output this morning, seemingly it was producing extra but wasnt sure and waiting for midday peak - it started consistently dipping around 11am. "Weird, no clouds, what the ???" I thought.
It dawned on me - the newly installed panel has a small chimney that may be casting a shadow on the new panel.
But surely that can't be? The dip showed lower production than what the 7 panels on their own would produce!!! Surely with shadow on 8th panel I'd still produce 7 panels plus one additional "downgraded" panel???
Anyways, climbed on the roof, and there was indeed a small 8cm by 8cm shadow right at the bottom of the newly installed panel (total array size 8m x 2m, size of each panel 2m x 1m, so the small 8 x 8cm shadow really was comparatively tiny).
Long story short, I cut the chimney - no more shadow, and the PV output immediately jumped by almost 25%!!!! 
(See image below)
 
I understand any shadow will handicap the system somewhat, but didn't realize how much it would actually handicap the entire array! Wow, lesson learnt, if any part of your array gets shadow throughout the day then either get rid of that shadow, or split into 2 or more separate arrays to minimize the effect...

I had my faulty US3000C replaced under warranty and before I sent it back I took some pictures to share with everyone. I did not strip it down completely for obvious reasons. Would have been interested to see what microcontroller and mosfets were used in this model. Not my best pictures but some are better than none.
Things to note; the battery packs which houses the cell pouches are now encased in some form of metal with a plastic top cover. The other distinct difference is the new board, now only one single board that handles Comms and Power management, probably costs less from a manufacturer perspective but this is the new V10R04 board revision. The same board is found in the US2000C models. Currently v1.9 firmware is available for them. The other notable difference is the orange cables joining each battery pack in series.
I was happy to see the improvements made. So thumbs up to Pylontech!

 

 

 

 

I run my Pylontech’s down to 20% DOD every night and SOH is now at 99% after eight months of cycling every day, so trying to get the quickest ROI.
 The batteries reach 20% SOC around 4:30 am and grid kicks in and I might use just under 1 kWh by the time pv production picks up, so for my needs, Eskom is cheaper than an additional battery for quite a few years to come