BGb

Hi Bobster, I've not been on the site for a while. I logged a fault on the Goodwe website on Sunday 18 th May and called them the next day. Sisanda from Goodwe help desk ran some remote checks and within a hour gave the following feedback.
"the inverter appears to be physically disconnecting from the grid. We have reviewed the settings on our side, and everything is configured correctly.
 This type of issue may indicate a potential problem with the grid connection itself, such as fluctuations in voltage or frequency, poor wiring, or an unstable grid supply. It could also be caused by external factors like loose connections, faulty breakers, or grid protection triggering due to irregularities.
 We recommend checking the physical wiring, grid stability, and any external protection devices to ensure they are operating as expected."
Only logging a faults normally takes longer than a day to get feedback.

Thanks Cef, installed without a problem it looks great and the weather widget works fine. I need more time work with the utility for the momen the focus is to see how best to extract the data (the dark background and figures makes it difficult to read), the 3D bars and legend seems the clearest for hourly data.
Thanks again, its of great asssitance.

@BGb
Well, the truth is, I haven't received much more motivation from forum users to continue uploading subsequent versions, and I'm struggling to prepare a new one so it looks good in the forum's download area. I'm sending you a Google Drive link where you can download a fully functional version, although not the one I'm developing. It may have a bug that I'd appreciate if you could report to me. In the "Events" tab, you'll find a bug in a feature I'm implementing, but that doesn't work well yet, related to unexpected photovoltaic power outages. The idea is for the system to alert you with an audible alarm. I had an arc flash in my installation due to a dubious MC4 connector I'd had since 2017. A fire started in the connector while the arc flashed until the power to the entire string was cut off. The idea behind this feature I'm working on is to at least warn you and give you the opportunity to react in time if a fire breaks out on your roof. This guarantee of at least one loud audible warning can only be achieved through a real-time SCADA system.
Follow the installation instructions in the .txt file once you unzip the ZIP file.
https://drive.google.com/file/d/1EwOGCG4DpBgTaV7C9FaVcv6J-euCZsOv/view?usp=drive_link
Here is a YouTube video (with many editing limitations) of a previous version (4.25):
https://youtu.be/G22gsCb9wHo

My Goodwe inverter heats up to over 60 degrees, inspired by BrettB I used 2 fans from and old PC, and a 12V charger that I had lying around. The fans fit nicely about 8 cm below the inverter. I salvaged aluminium angle used by tilers, initially taped and cable tied the angles together, but later attached to the fans with screws. Plastic file divider (red) used to channel the airflow. Money was spent on a Digital Temperature Controller with LCD Display XH-W3001 (12v output model) R229 and a R40 plugbox for power. I've set the W3001 controller to activate the fans at 45 degrees and to turn off at 37 degrees. The temp sensor was located at the back of the inverter. So far working well although a bit noisy, one can buy quieter fans.  In my case the Goodwe inverter generates maximum heat midday so noise not an issue. A couple of pictures of the components used and installation. Max temp during recent heatwave was 45.8 degrees for a hour or so with fans on.

You need to measure and record the municipal meter and the house consumption.

Monthly I record the CoJ Pre-Paid meter and the total house consumption using a Hiking DDS238-2 meter.
The Hiking DDS238-2 measures the consumption after the inverter.
Instead of the Hiking DDS238-2 you can extract the consumption data from your inverter.
I use Excel to record:

Purple = CoJ Meter consumption kWh
Green = DDS238-2 Meter (Total House Consumption) kWh
Blue =  Self Solar = House_Total-CoJ Meter. i.e. difference between CoJ and Total house consumption. This is what comes from the Sun aka SELF generated.
 
 

Note the warranty on the Pylontech UP5000 differs from the US5000 (5 yrs vs 7+3), a battery with a longer warranty should have a better resale. Can't comment on the Dyness.  The pylontechs tend to be compatible with more inverters.
 My personal call would be 2 batteries and solar panel. The reason
Solar panels will reduce you electrical bill and help with payback
If the grid is off for an extended period and weather permitting you will be able to recharge the batteries
You and family will learn how to live with solar, eg run power hungry appliances when the sun is shining, reduce consumption when there is poor solar power, you will get a feel for extra panels needed etc in future
Adding another battery is relatively simple (could be DIY less than a day) getting solar installed is a much lengthier process, and may be more expensive if done on its own rather than part of a complete job.  You would also need a COC (dont think thats required if you add a battery)
You may be able to find good 2nd hand batteries at a significant lower price vs new.

My DB board is split into what the electrician called essential and non essential loads.  I suspect your backed up loads = essentail.  I think you did indeed answered you own question to check if its part of the essential (back up) loads turn off grid power and see if you can still power the pool pump.  If you can its on the backup load. The risk as you would know is that if the pump turns on during load shedding and there is insufficient solar it could drain your battery.

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

Hi  @PilgrimToHyperion
Glad it helped.
Make sure you have the latest Goodwe firmware, mine is running 1242416 (apparently there is a newer version).  My system now automatically reboots if tripped after say 2-3 minutes, sometimes longer.  You can check firmware verion by selecting Inverter in SEMS it is shown right at the bottom.  
I've registered as an installer and can now via SEMS modify the mode and  DOD, there is a thread below towards the end by @paul99 that explains how its done.
You have to save the values, in the "installer" setup I dont think you have to restart the system.  The other big benefit of the "installer" is that you dont have to log on to Solarwifi. 
Connectivity with the inverter is is acknowledged as being poor, and you have to double check that the settings were passed on to the inverter.  I've sometimes tried more than 10 times to get it to work. Cef's utility also show the Mode and DOD but you need to shut the software down and reload to see if the values were changed. 
I've also stated using eco-mode, and am able to squeeze a couple of extra watts from the system instead of clipping production at 4700 w
 
 
 

ok guys here are my settings for loadshedding small or large 
My aim is to deplete my batteries down to 40- 50% at night
You will notice i start and end on uneven hours as loadshedding is always on even hours so i will always overlap by 1 hour either side of loadshedding if loadshedding is below stage 5 (stage 5 and higher is 4 hours after each other at certain times)
ECO MODE    if you dont put any settings in at night (ie when there is no pv)  it will run those hours as if it is in "General Mode" only drawing what it needs from battery to satisfy the load
i set no1  01:00-05:00 charge at 5%  (this forces the inverter to load say 600 watts in my case from grid for those hours Your load will get added onto this 5%) This 5% is about what my house draws at night when everyone is asleep so when its loadshedding it goes into "general mode" mode and only draws from battery what it needs to satisfy the load and when loadshedding is over it keeps the batteries at whatever % the battery has dropped to because the 5% will satisfy the load without drawing any more power from the batteries
I have now switched this off so it runs as if in general mode from midnight to 05:00 as my batteries can carry me from 00:00 till 07:00 but if yours cant here is an option to top up the batteries or keep then from discharging further before sunup
i set no 2  06:00-10:00  discharge at 1%  This is not for those that can't discharge to grid ,but i can. This forces discharging the batteries at a couple of watts and stops the pv from charging the batteries because i have found that if i charge my batteries at near noon when pv is high i can draw up to 7kw from my pv (load+charging batteries+export to grid, i must also add that the inverter is set to 50hz not south africa, see attached pdf for proof thanks to the software from CEF)
If batteries are near full at 11am then i can only draw 5.2kw from pv when sun is at max  (load+export to grid)
Now for the last couple of days it has been raining and cloudy mostly every day so the batteries dont get charged enough for the evening
i set no 3  13:00-1600 charging 6%  (In my case this is about 1 kw drawn from the grid for the battery + the load gets added to this if no sun.) The sun will always give more than this on a sunny day then this setting does nothing,but at least when its cloudy my batteries will get charged for the eveningfrom 13:00
if PV is exporting more than the load it will add the left over pv to 6% and charge with that up to max that the battery can handle and export the rest
If PV is less than the load it will draw the extra load from grid and charge at 6%
So from 16:00 till 21:00 all the cooking etc gets done and then it all quietens down and i dont set these hours so it acts as if in general mode drawing from battery once the sun sets (hopefully the batteries will be 80-100% depending on loadshedding)
i set no4   21:00-23:56 charge 10%  This will top up the batteries to about 80% after the evening usage and loadshedding
Remember loadshedding usually kicks in during these hours  then the charging stops and discharging happens
If your batteries can carry you thru the night then you will only set the daytime in case it is cloudy
The times that you set nothing the inverter will act as if it is in general mode
Hope this helps someone out there
Regard
Paul
 
screen.pdf

hi Miko
Just to clarify your statement about setting remotely
In SEMS portal app you can set the inverter remotely
Scroll down to bottom
Where it says inverter click the GW5048D-ES
Next to monitoring click  configure  click the box i agree and press next
Click the arrow next to working mode and you can set your different modes remotely
Hope this helps

i just want to add my 2 cents
PV master economical mode is the only way to charge or discharge when you want it to, but having said that ,the chinese dont think like we do
So in economic mode you have to ask yourself what don't i want the inverter to do
Firstly if you change between modes leave no 1 setting alone on charge at 10% from 00h00 to 23h59 otherwise if you pick ups mode your no 1 setting will be lost every time
So in my case i have 6.8kw of solar connected 4kw to 1 string and2.8kw to other string
Sun gives most power between 10am to 2pm
so i only want to start charging from 10am onwards to get the most out of the pv
i set no 2  to discharge at 1% from 7am to 10am          (if you set discharge mode the inverter will not charge and visa versa if you set charge mode the inverter will not discharge the batteries) The hours you dont set anything it will behave as if in general mode
Then because we are in stage 6 loadshedding i know that in the evenings i will get between 2 to 6 hours of loadshedding every night
that could pull my 10kw of batteries down to 50% and then i would not have enough to see me through till the next morning when the sun takes over the load till 11am
so i set no3 to charge at 21% from 3pm till 11pm ( because i am in charge mode the inverter will not discharge the batteries during this time, remember loadshedding will kick in for 2 to 6hrs in this time so that when the power comes on the batteries will charge from the grid seeing as the sun has set
Always try to set on on or off on odd hours as loadshedding always starts on even hours ,that way you will always get half the benifit if loadshedding is only for 2 hours
also try to use a lot of power between 10am till 2pm if its loadshedding as the inverter will just throw away the extra pv as the grid is down
i get on average about 5.2 to 5.3kw out of the PV while its charging the batteries  i put dishwasher on and try to get the load to 3kw and rest gets pumped into the grid if its not loadshedding otherwise you just lose that pv power
I have already got 7kw out of the array this way for about half an hour. 4.6 kw between the load and export to grid  and maximum charging of the batteries
Although i think this is a bit wishfull as my goowe says the backup output is about 248v and if i measure it it is about 225v
The best i have achieved out of my 5048D-ES is 38Kw in 1 day 24 and 25 dec 2022, Yesterday i got 37Kw 15-1-2023 and i live in pretoria east
Hope this helps someone out there

Some nice data out there.
I'm in Pmb. There is a weather station 5km fom my house as the crow flies from where I can download data.  It rained a lot more in more in Dec 22 than previous years, solar radiation has also been lower in Dec 21 and Dec 22 vs Dec 21.  I am able to supply excess power to grid which is obviously not possible during load shedding and load reduction, I suspect Dec 22 PV production should have been higher.
Rainfall is not a good driver of PV as three events made of 50%+ of the Dec 22 rainfall, if available one must rather use solar radiation. Judging from the news Tshwane also had exceptional rainfall events in December
 
Row Labels SRAD Mj/m2 Sum of PV(kWh) Sum of Rainfall 12 20 590 651 147 12 21 513 584 247 12 22 544 598 321     Dec 22   74 hours without power

Some nice data out there.
I'm in Pmb. There is a weather station 5km fom my house as the crow flies from where I can download data.  It rained a lot more in more in Dec 22 than previous years, solar radiation has also been lower in Dec 21 and Dec 22 vs Dec 21.  I am able to supply excess power to grid which is obviously not possible during load shedding and load reduction, I suspect Dec 22 PV production should have been higher.
Rainfall is not a good driver of PV as three events made of 50%+ of the Dec 22 rainfall, if available one must rather use solar radiation. Judging from the news Tshwane also had exceptional rainfall events in December
 
Row Labels SRAD Mj/m2 Sum of PV(kWh) Sum of Rainfall 12 20 590 651 147 12 21 513 584 247 12 22 544 598 321     Dec 22   74 hours without power

@BGb
Latest firmware installed by Goodwe technical service on my system: 242417. Approximately 2 months ago.
 

Hi @BGb !
1.) I have noticed that with old or low power processors the error rate of UDP packets increases. Also, in the next revision, I am going to correct this and leave it as optional for the User in the "Parameters" tab.
2.) That's right. I would be very surprised if they matched exactly. kWh is an integration of the samples over time. I do this integration with the samples second by second. I don't know how often the SEMS Portal does them. But we already know that the transmission of the data to the sems portal from the power inverter is never done at this sample rate of 1 second or less. Likewise, I don't think that for the calculations they consider the conversion efficiency of PV Energy to Alternating Current, so if you put 100% in the Parameters tab instead of putting 97%, the calculated Power will simply be the product A x V. You will see in this case that it is a little closer to the value that the SEMS portal shows you. In future revisions I will incorporate the "Auto Use" of the PV Energy to separate: Battery Charge + Essential and Non-Essential Loads from the Energy Exported graphically in the "GR" Tab
3.) I don't think so. Obviously if your PC is not running 24 hours, it will effectively have blank Accumulated Data during the time it is off since the Program must be running (i.e. it does not download missing data from SEMS or get any accumulated data that the Power Inverter could save to its own memory if it does so at this time). On the other hand, don't forget that the Totalizers in this software are closed Every Hour. Although graphically you can see the results in minute of hour in the "GR" tab.
In case the program is running and there is an interruption in the information it receives, either due to failure of the WIFI antenna of the power inverter or due to problems in your LAN, the current version will indicate the instant of the interruption or " Information frozen" and the re-establishment of communication. You can check it in the "EL" tab or errors/events.
4.) Sure! I can contemplate it in following revisions. For now you have the data in a .csv file almost second by second of several days and they are grouped by Minute, Hour, day, Month and Years only in a Graphical way.
5.) See answer 3.), however, in some future version I hope to be able to read the information from the Sems Portal to complete the data that is eventually missing with "hourly resolution" for cases of PC failure, Operating System or eventual freezing of the system itself software system.
Warning Number: 8
If you look at the current version of PV Master, you will find this same Warning in its Alarm Log.
I also have Pylontechs US3000C and from time to time this warning appears, which then clears up, returning to Normal condition after a few minutes. It appears when the batteries are charged to 100% of their SOC. I wouldn't worry if it disappeared after a few moments.

I forgot to put in the description of the new version that the database of all second-by-second fundamental electrical and operational parameters was extended to 5 (FIVE) days. This can be downloaded in a .csv spreadsheet (approximately 432,000 rows). In general, the column headings are self-descriptive, but if you have any questions, please ask here and not in private, so that everyone benefits.

Hi @BGb The firmware 242416 was installed remotely by the Goodwe Technical Service. The only thing I noticed was that the WIFI module that was disconnected from time to time, never disconnected again since then. I also have pylontech 4 US3000C batteries and everything started to work fine when I made the specific cable for the correct operation of the Pylon BMS with the Goodwe.
There are times that I have made changes with the PV Master that have not impacted the power inverter. Previous versions had sometimes strange behavior. I solved it, confirming all the configuration completely (item by item), accepting the changes and then closing the app. You shouldn't have a problem with that.

More confirmation of what other users have said, winter lowest daily PV but less rain vs Summer high daily PV but more clouds and rain.  Axis on left daily PV.  The daily production very different between seasons but monthly production about the same. My installed capacity = 6.2kW

More confirmation of what other users have said, winter lowest daily PV but less rain vs Summer high daily PV but more clouds and rain.  Axis on left daily PV.  The daily production very different between seasons but monthly production about the same. My installed capacity = 6.2kW

I used similar spacing to what in your photo but with only 4 roof hooks per rail (2 per 3.3m rail), and to date 2 years 3 months later its still ok.  You may want to check if your panels will fit in portrait mode, mine are 2 m x 1m in size, if your tiles are 30 cm each, space may be tight unless you mount the bottom ones in landscape mode.  The shade in the bottom section is also not good as it will negatively impact on performance of your panels, if possible rather move the panels away from the shade.   In theory there is a benefit to maximise the angle of the panels to the horisontal, maximise the adjustment of the bracket at the top and minimise it at the bottom, could give you a couple of extra degrees...
 
 
 

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

These guys are doing the longer term testing for us
https://batterytestcentre.com.au/batteries/pylontech-us2000b

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

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