Paulcupine

I have to ask why you're heating water at 10pm... is someone bathing/showering at midnight?
You have excess solar available during the day that isn't being harvested. You will be better off if you can move some of that night time water heating to the day time. The alternative is to get a bigger battery, but that isn't nearly as cost effective.

EDIT: I see you're only using half your battery. There is no load shedding at the moment... why not allow the battery to cycle down to 10%?

Crying in Capetonian @ R3.91/kWh, and R4.75/kWh after the first 600kWh

Luckily I only bought 800kWh in the last 12 months.

Actually switching off things like game consoles and media PCs can make a significant difference overnight. I can always tell when the kids have been up late playing games. "Base" load goes from 200-300W to 500-600W. It's also interesting to see how the duty cycle on things like fridges and freezers is reduced in the winter. The 5 or 6C lower ambient temperature in the house makes quite a difference. My full height fridge and freezer use about 1.5kWh/day in summer but only around 1.1kWh/day in the winter.
Of course, you lose again on water heating in the winter. Input water temperature is much lower especially around late July/August, so energy spent heating the geyser is much more.

My geyser had a 4kW element which I downgraded to 2kW. It now runs anywhere from 2 to 5 hours depending on how cold the water is to get fully hot, so interpolate for less PV available. Imho, 1kW is too little. Since I upgraded my solar I'm actually thinking of upgrading it back to 3kW.

I agree. Battery prices have come down and these are nearly "half" used. Seems like they should be going for under R10k each, all things considered.

It wasn't quite as bad in our house but the filling of a 2L kettle everytime to make one cup of coffee made me go out and buy a 1L camping kettle.  It also has a smaller element, so now nobody is willing to wait for it if it is full.  Problem solved, and the cleaner got the old one for free.

It wasn't quite as bad in our house but the filling of a 2L kettle everytime to make one cup of coffee made me go out and buy a 1L camping kettle.  It also has a smaller element, so now nobody is willing to wait for it if it is full.  Problem solved, and the cleaner got the old one for free.

Mute topic, as global warming hysteria is all nonsense, and human intervention is irrelevant, as the sun's cycles control temperatures on earth.
What humans can do is poison the earth and atmosphere with many toxic elements been dispersed in the atmosphere and on earth. This is a different discussion though. 

He does not know what he is talking about... daylight (not direct sunlight) will produce ample Tension, but very little current (mucho Volts near nada Amps), whereas direct sunlight will add the Current to the Tension... thus, panels in parallel have practically no influence on each other...
 
Off grid proper, here since early December... water heating is done by solar hot water cylinder, 12 X evacuated glass tubes into a 100 litre  hot water cylinder (low pressure, Jojo tank on 6 or 8m stand), no municipal anything here... your Eskom fees look half way reasonable, compared to what they charge here... hence, off grid.
Doing hot water with evacuated tubes, saves lots of electrons, lots of people on this forum prefer electrically heating the hot water cylinder, but direct solar is about 60 to 70% efficient, I read the other day, and solar panels, maybe just above 20% by now, then add in MPPT efficiency etc... so here in summer hot water will give you 3'd degree burns, if you don't mix in copious amounts of cold (luke warm, Kalahari...) water.
The inverter is a 5kW SunkenSynk and initially with a 8.2kWh BSL battery, end of December I added 16 X 304?5? whatever, call it 16 X 300Ah cells with a JK BMS in parallel with the existing 8k2Wh BSL, works fine, I don't have comms yet with the bigger battery and the inverter, but it tracks the data from the smaller battery roughly, at least good enough that the 300Ah is within 4 to 6% SOC of the smaller battery. So don't panic about needing to match up batteries to be the same, the only thing that has to be the same is the cell chemistry (pretty much should be LiFePO4) and the amount of cells in the battery, should be 16 cells, this then would allow you to add any capacity battery to the existing one. Here the 23-or so kWh battery is usually anywhere from 53 to 61% SOC by the time I roll out of bed and after kettle, coffee etc., by the time the sun puts a bit of charge back into the battery, we're anywhere from 46 to 51%, or so charge remaining... we had to manage things here and there when a cloudy day came along (rare here, seems to be happening more in recent time, though) but have not had to shut the house down yet, luckily.
Once you're off the grid, you may become an energy Nazi, like me, monitor on, on standby, draws too much power, switch it off, better yet, yank the power cable, when not in use/needed. You will in time look at everything that consumes energy and get cheesed off at certain items being seriously wasteful in consuming 30 or 40W, for no reason whatsoever... you're likely to find out these things in the fullness of time 😉

NE and NW will react on light and should not differ much.(volts) The output amps will vary between the 2 but each string will provide the amps it can during the day. The different amps will just combine as they are in parallel. 
 

Not necessarily, for example, the DEHNGuard basic above, has a gas arrestor in series with an MOV to reduce leakage.
Also, the indicator is supposed to turn red before the MOV fails, which also shorts the input to ground mechanically, tripping the upstream breaker.

Yes you can do this with scheduled charge with the most recent GX firmware update (about 2 months ago iirc).  
Set your overall min SoC to the lowest you want your battery to go at any time while the grid is available (40% in your case).  Then set a scheduled charge from sometime in the afternoon near the end of your PV generation time for the number of hours to cover until you are willing to go below 75%.
In the scheduled charge set 75% as the charge level and enable self-consumption "from PV and battery".
Note that the scheduled charge will ALSO charge your battery from the grid up to the 75% level, if it is not already above this.  Since you don't want the battery below 75%, this should be fine and only actually charge the battery from grid if you have had too little PV yield that day.  
As an example, set the scheduled charge to start at 4pm and run for 10 hours.  Your battery will discharge to the 75% level during the evening, then you'll switch to grid until 2am, whereafter the battery will discharge again down to 40% potentially.  Adjust times and levels to suit.

Last update from him was about two weeks ago.  The testing on the new meter is behind schedule and they are now aiming for Q1 2024.

There's a whole school of thought on the two dishwasher system in modern kitchens now.  Dishwashers are remarkably space efficient in how much you can store in them.  It turns out it actually makes sense to give up the cupboard space.  You pack one dishwasher with dirty dishes until it's full, then run it.  You use the clean dishes from the one dishwasher and pack them directly into the other one when used.  When it's full then you run that one etc.  Some small amount of dishes still get stored in the cupboard - perhaps only the last few before you want to start packing the not quite empty dishwasher again.

Also, they don't understand that boiling one mug of water is faster than filling the kettle to the full 2L.

My setup consisted of:
Victron Multiplus II 3kVA
Fronius Galvo 2.5 on Multiplus output (with 9 x 250W panels)
Victron MPPT 150/45 (with 6 x 360W panels)
Victron Cerbo GX
3 x FreedomWon Lite 5/4
Carlo Gavazzi ET112 meter on grid input
I built this system up over time, slowly adding more battery, then more PV panels then more battery again and reached the point where I needed more inverting power.  I got an extra Multiplus II 3kVA, studied the parallel installation documentation and watched the training videos over and over.
One of the main considerations when doing this is, that electrical cabling must be as close to the same impedance on each inverter in the parallel system as possible.  This is achieved by using the same type of wire and making sure they're the same length from each inverter.  
After I had installed everything, done the necessary firmware updates and reconfiguration I fired everything up and it all appeared to be working... until the next day.
My grid setpoint is set to about 10 - 20W and for the most part this is fine.  There is occasional brief grid feedback when a large load (eg. geyser) is turned off, but it stabilises pretty quickly.  On day 2 I noticed that when my 2kW geyser (wired on the inverter input side) switches on, the Fronius PV gets cut back to near zero and the Multiplusses started inverting to the level that they were taking all the DC coupled PV and draining the battery. 🤔
I switched the "feed excess AC coupled PV to grid" setting on.  The result was the Fronius ramped back up to full power, the load was carried and the batteries getting some small charge and now the whole system was feeding 250W back to the grid.  🧐  Switching the feedback setting off, resulted in the Fronius cutting back and the batteries being discharged again.
After some head scratching and rechecking of my installation I found that while I had paid meticulous attention to ensuring that the cabling on the AC outputs of each of the Multiplusses was as identical as I could get it, I had not paid enough attention to the AC cabling on the AC input of the Multiplusses.  I pulled them out and measured the one at around 2m and the other at 1.5m.  
I cut the longer one down to the length of the shorter one as accurately as I could (probably within 5mm) and reinstalled.  Voila, problem solved.
So why did this problem manifest in this way?  The documentation all states that if cables are not identical, the load will not be evenly distributed between the inverters.  It says nothing about grid feedback or AC coupled PV being affected. 
The best explanation I can come up with is: the slave inverters input cable was the shorter one, meaning that it was the one feeding in more energy.  The master was the one determining the load and deciding what the energy feed in level should be (per inverter).  The result was too much energy being fed into the grid side of the inverters.  The ESS running on the GX then saw grid feedback in excess of the grid setpoint and decided there should be less power being fed back.  It then chose to cut back the Fronius output instead of the Multiplusses.  The Multiplusses dutifully complied with the power request from the GX by drawing from the battery when the DC coupled PV was not sufficient.
It's a bit of a complex interaction and a quirk of ESS that I hope Victron will address at some point.  If the battery is not full, there should be no reason for ESS to cut back the AC coupled PV output, and even if the battery is full it should cut back the Multiplus output first before cutting back the AC coupled PV.  

Your inverter is not a calibrated device, so apart from losses you will also have measurement inaccuracies.  Depending on the measurement mechanism, the inaccuracy is also likely different at different loads.

ACDC Direct and no doubt other retailers sell copper busbar in various sizes.  I bought 1.2m x 20mm x 5mm ones from them for my old 12V parallel battery bank.  They have pre-drilled and tapped M6 holes every 10cm or so.
 
Paul

ACDC Direct and no doubt other retailers sell copper busbar in various sizes.  I bought 1.2m x 20mm x 5mm ones from them for my old 12V parallel battery bank.  They have pre-drilled and tapped M6 holes every 10cm or so.
 
Paul

ACDC Direct and no doubt other retailers sell copper busbar in various sizes.  I bought 1.2m x 20mm x 5mm ones from them for my old 12V parallel battery bank.  They have pre-drilled and tapped M6 holes every 10cm or so.
 
Paul

I just realised one more factor that may become important when we hit stage 15...  AC coupled PV requires a grid to produce power.  If your AC coupled PV is on the output of your Victron, as mentioned above, no problem UNLESS your battery is completely depleted and your Victron inverter can't start...  Victron inverter off means no grid, means no AC coupled PV.  You need a generator or grid to get going again.
DC coupled PV is powered by the panels connected to it (I think).  So even with a dead battery, the MPPT should fire up and start charging it, allowing the inverter to start up afterwards.

https://www.takealot.com/mellerware-travel-kettle/PLID17260023
I got this one.  It has the advantage of being smaller too, so no more boiling of 2.5L of water for one cup of tea.

Om te meet is om te weet.  I agree with others here that you should measure before you spend.  I ran one of those Efergy meters in my house for about six months before installing anything.  Once you have a handle on your consumption - what's what, what can change and what cannot - you will be far better placed to buy appropriately.
While one could go for a system that is backup power only with grid charging, remember that you then only have costs.  Batteries don't save you money and every kWh that goes into them you only get part of a kWh back.  PV panels are both the cheapest part of your system and the only part that makes you money. 
The 2kW worth of panels I put in a little over three years ago have generated 10MWh of energy.  They have already paid for themselves and part way for the Fronius they're connected to.  A little over two years ago I added another 2kW of panels and those have already generated around 7MWh.  Once the panels have paid for themselves, they start paying for the rest of your system - at least that's how I see it.

As P1k says, it's not completely off the battery.  What happens when the battery is full and the DC PV cut back and a load comes on is that the inverter starts to draw from the 48V DC bus to invert for the load and the MPPT ramps up its output to match.  This takes time, so some energy is effectively taken from the battery and then pushed back in a short while later.

As P1k says, it's not completely off the battery.  What happens when the battery is full and the DC PV cut back and a load comes on is that the inverter starts to draw from the 48V DC bus to invert for the load and the MPPT ramps up its output to match.  This takes time, so some energy is effectively taken from the battery and then pushed back in a short while later.