In that case… 150kW AC-coupled system, no batteries. Fronius Tauro, Fimer PVS-100-TL family, or maybe even a nice large Solis. They make big ones too.
Of course, for this kind of money, a consultant might still be the way to go.
Yup we have the guys of Candi Solar busy doing an assessment. Thanks.
This will also not run in LS, correct?
AC-coupled = Grid Tied = you do what the grid does (die when it dies)
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That’s a pity, thought you could maybe have a hybrid inverter with a smaller battery so as to run the PV when LS happens in the daytime.
Correct.
If you want to run during LS, you need batteries. And THAT is where it gets costly.
Just grid-tying with no batteries, is THE best and most affordable option, saving you the most the fastest on the Eskom bill.
The moment you go batteries on a big system, the sums get very high very quickly.
It gets “complicated”, the size of the battery needed. There are lots of “small prints” using a big system with a smaller battery.
The battery must meet the inverter size and must have the panels to power the load AND recharge the battery on the same day.
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150kW of load fed from a battery isn’t in the mortal realm of anyone, bar a James Bond villain.
Now, when it comes to grid-tied, remember this: you will need to oversize the panel capability by a minimum of 30% to the inverter.
Do not expect 100kW of panels to deliver 100kW. You will probably average closer to half of that.
So, plan to go very panel-heavy.
And it is money well spent.
There are limitations on how small you can go, if you still want the whole 150kW to be available when the grid is down.
The best case scenario I’ve seen, on that power level, was with a SMA SunnyIsland setup (SMA microgrid setups are not cheap), which allows the PV to be twice the size of the battery inverter and battery bank. With such a setup, you’d still need 75kWh of battery with the capacity to charge at 1C, and potentially 150kWh of battery if you use the more commonly available 0.5C types.
Even with a hybrid inverter that allows a really small battery (comparatively speaking), you’re still in for a very large battery, I still think 75kWh is what you are looking at. That’s half a million in battery alone.
Yay! Thanks all. I feel 100x more clued up :). Then option one it is. I feel more confident on that now!
Just be aware that the E/W panel orientation of 107 kW is only sufficient for a 50-60 kW inverter.
You can do the maths from there to work out the panels you need for 150kW.
( And E/W orientation is the correct way to go, by the way).
You will not regret over-estimating your panel requirement.
Twenty-five years of life of no moving parts – what a pleasure.
Panels pay themselves off in less than 4 years.
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I found this part quite important on my setup cos if I go a few days cloudy and the battery doesn’t charge up full, the next day that it does it has cells that are off and it takes a while to balance. My battery likes to be full.
I also agree fully that more panels than battery is the best way to go but you need to have a balance so that your battery doesn’t get overused by the system.
I think you need two systems installed one hybrid with battery powering the lights and small loads so your lights will always be on, then the big loads and pumps on a grid tie system without batteries just to save money when the suns out, maybe this could be expanded in future to include batteries.
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Does feel that way, will share option 3 when it is done.
Like this I would not know. My assumption was they are covering 2 x 50kw with 107kw of panels. But you saying that the buffer has to be much larger. Makes sense if we factor in the Winter months and cloudy days. Got it, thanks 
.
I am not referring to temporary poor production factors.
I am talking about expectations being 30-40% less than rated in times of good production due to orientation and slope.
A 500W panel can make 500W, but only when the moon is in the Seventh House
and Jupiter aligns with Mars.
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Got it! Loud and clear 
. Hehe.
Those calculations are garbage. You can use 5kWh/m²/day x panel area x efficiency. Alternatively 5kWh/m²/day x panel capacity.
The way it presents it is a horrible mis-match of units. (and the final number also does not match the preceding calculations)