Thank you very much; this really helps a lot! Our roof space will probably be the limiting factor here; we will be able to squeeze in a maximum of around 16-17 kWp, so we will probably work around this in the way that you mention.
Thanks again leon.davibe, I get what you are saying; we will keep on reworking the numbers until everything settles into an optimal answer - I think we are definitely making nice progress along this path now.
We have now had a look at web resources like globalsolaratlas.info and pvwatts; for our roof orientation and other constraints, these converge on a basic requirement of around:
2 x 5kW Sunsynk inverters;
13kWp;
48kWh batteries @ 90% DoD.
The single remaining issue seem to be the 'black start'...
The main issue for us is one of reliability and peace of mind - some things are just priceless. Using your numbers: we do not want to spend say the R300k and have Eskom fail us during their 5% window.
Thanks for your response! In answer to some of the questions/remarks:
* It is a hybrid (both home and business).
* Single-phase is OK.
* I have not yet explored alternatives for a black-start situation; thanks for this suggestion - do you perhaps have any advice in this regard?
* We have around...