FriendlyToast

You can use the Sunsynk as a Grid-Tie with no battery. As @Scorp007 said though,  it will not work if there is no Eskom power and it is in grid-tie mode as it has to have a main supply frequency to sync too.
Best plan IMO would be to purchase a small battery that is easily expandable, a Pylontech 2000 or something similar that can be picked up relatively cheaply 2nd hand, and connect that. Will not be able to provide a lot of power but will enable the inverter to run with no Eskom power and as long as you are not going to try and pull more power than the Sun + battery can provide you will be ok. 

@FriendlyToast, the Sunsynk CAN made to run pure grid tied, under the Battery mode screens, there is place that you tick "No Battery "'

Keeping your battery charged at 100% is also not a good idea. 
 

Thanks! 

Will check out the sizing tool. I didn't know about the PV voltage limitations or weather, will have to calculate accordingly. 🙂 Any suggestions where to start window shopping for pricing? I know these guys have a store as well and then sustainable, but not keen on getting a second home loan with sustainable 😅 There seems to be so much solar shops and installers these days, not sure who I can trust.

I just wanted it to be crystal clear. Some may de disillusioned after spending 40-50K and then realising that they haven't the capability to mitigate load-shedding during the day whilst the sun shines. As long as they are aware upfront, that's great. 

Do shop around. The solar panel prices have gone up by quite a bit. My panels I got last year at R3000, are now around R4000.
The Power Forum Store itself and then there are a couple of others.
https://onlineshop.gcsolar.co.za/
https://gwstore.co.za/
https://www.inverter-warehouse.co.za/
https://shop.thesunpays.co.za/
https://thepowerstore.co.za/
If one had the funds, buying by pallet saves quite a bit. Could resell the excess. Or if one knows another 2 or 3 people that are also shopping for panels it really is worth the while to buy a pallet and share the panels amongst the interested buyers

The PowerforumStore is great. The difference between PFS and many of the others will become apparent after you have had a conversation with Steve. Their pricing is also excellent, considering the service that Steve gives, they are not drop-shippers or box-droppers. He designed my system fully, supplied all of the kit and also recommended an excellent installer. The installer first did a complimentary site inspection before quoting, and we also had communication throughout the delivery and install whole process, right up and until everything was working staisfactorily. 
By contrast, the other players were streets behind them, quotes for the same thing varied between 250,000 and 450,000 rands, and I got the impression that they didn't have enough knowledge or experience on the products, so they kept loading the prices to cover themselves (in case their solution didn't work). They were also very inflexible, and didn't want me to suggest any changes, once again poor product knowledge and experience. One in particular wanted to charge me a professional service and call-out fee just to do a site inspection, another sent me three successive versions of the same copy and paste proposal, every version with more errors than the previous.
The Powerforumstore service experience is highly recommended.

Thanks! 

Will check out the sizing tool. I didn't know about the PV voltage limitations or weather, will have to calculate accordingly. 🙂 Any suggestions where to start window shopping for pricing? I know these guys have a store as well and then sustainable, but not keen on getting a second home loan with sustainable 😅 There seems to be so much solar shops and installers these days, not sure who I can trust.

Yep.
Also, not all of us can afford a motorised sun tracking pole mount that allows us to automatically adjust panel tilt and azimuth (E<->W orientation). Most of us make do with the roof that our houses were blessed with. Even with a perfect azimuth, altering panel pitch can be quite expensive in terms of mounting hardware, and then there are differences in the angle of the sun in summer and winter. So one usually compensates by adding more panels, it's far cheaper. Some members have great results even when mounting of the "flat" roof of a carport. 
A good sizing tool here https://unboundsolar.com/blog/string-sizing-guide
Things to watch for:
Maximum voltage. MPPT controllers can easily control Amps, but not voltage, so exceeding the maximum PV input voltage of a string can be very expensive. With the Sunsynk 5 and 8K inverters, best not to exceed 450V, even though there is a 500V maximum. Your location (and the minimum and maximum temperatures for your area , over the past 10-20 years). Solar panels generate more power when cold, and less as they heat up. If you design an array based on NOCT values, but if you get a cool summer breeze from the ocean in the middle of the day, you could also end up sending far more volts to the MPPT than you wanted, with devastating consequences. The quoted guide takes care of this as one of the steps. Maximum PV watts per MPPT. With inverters having multiple MPPT controllers, it's quite possible to size arrays that collectively exceed the power of the MPPT. The 5K Sunsynk's limits are 13A and (500) 450V, that means 5850W per string and there are two so that is theoretically 11,700Wp. This does not mean that it will work (although I have seen evidence of a 5880Wp array producing 7790Wp). So its probably best to be cautious and not exceed the Mav PV Isc figure on the sticker on side of the inverter. For my 5K Sunsynk this is 16.5A DC + 16.5A DC.  Size the string in such a way that it reaches the operating voltage of the MPPT as early as possible in the morning. For the 5 and 8K Sunsynk, this is 150V, and will be achieved earlier by adding more panels in series.    
 

Why would I want to add more panels (kw) than what the inverter can handle? Is it for those cloudy days? 

No need. Here I highlighted the values to look for. It looks intimidating as JA put 6 panel types on one tech spec sheet.
You will see the difference in VoC and IMp and also the PmaxW. Thus I suggest work on the NOCT as that is closer to the real world.

Correct. To compensate for the days where solar irradiance is not ideal.
Your inverter will clip the excess if and when it exceeds the max.
Also if you can get it, have a look at the panel manufacturers full spec sheet and rather use the NOCT (Nominal Operating Cell Temperature) figures rather than the STC (Standard Test Conditions) as that will provide you with the more realistic output expectations. Worst case scenario.
For example I expected mine to perform as per the STC. Only after I got Solar Assistant was I able to analyse and realise the reason why I have never seen more than 4,9kW from my panels which should provide 6,4kW in ideal test conditions. 

Everyone that I know with a similar setup says exactly the same thing. 
We need to compile a list of "Solar Power Defacto Laws".
1. You can never have enough panels. The vast majority of people increase the number of their solar panels within the first six months of the original install.
2. If you considering an EVT geyser, don't. Rather read defacto law #1.

Good morning everyone. 

I would like to start my off grid journey this year, finally being out of debt (except home loan). I don't have the capital to do everything once off, so hoping to be able to do it piece by piece. 

I have a couple of questions and hoping the community would be able to assist. From some research, it seems the most popular set-up is this: 
5/8kW Sunsynk Hybrid Inverter JA 540W Solar panels Some form of lithium batteries I was considering converting my geyser to solar first, but then people with existing systems mentioned that although it's less efficient to power a geyser, from PV panels, it is more value for money to get extra PV than say having a dedicated solar geyser kit. E.g. 15-20k extra solar panels vs a dedicated geyser system. 
What are the thoughts around the above for people that already have off grid/grid tied systems in place? Assuming I go piece by piece, starting with the inverter, would it be possible for the Sunsynk to be installed with one set of batteries and then later more added? I know it's not great to mix old and new batteries, so would this be possible? I know some inverters allows you to install multiple "packs", but I can't seem to find information on the Sunsynk/don't know what to Google for.  I average about 15-20 units per day, so I'm going to get myself one of those Efergy monitors, to determine when most power is drawn, but I assume it will be when the geyser is running. 
How do I calculate the battery and solar panel size needed? (Taking battery DOD, rainy days and so into account).  Note: There is no female in my household (yet, but I should cater for this anyway) so no hair dryers and things like that 🤣 Looking forward to some advice 🙂

I have 20 tube EV geyser, and 6600kWp solar PV, and on rainy days the 20 tube EV geyser is close to useless, whereas the 6600kWp of solar PV still provides just under 1 kW of power. I've had the 20 tube EV geyser for years before the PV install, and on non rainy days it's great.

Thanks! 

I'll continue reading and researching while saving up, but I think I have all that I need for now, 🙂 Thanks everyone!

Hi Friendly,
 
I went exactly the same route as you are mentioning. I splashed a bit and rather got the 8kw Deye inverter, but could only afford 12 380W panels and one 5.1kw battery. We swopped my Geyser's element with a 3kw element and at this stage when the sun is shining properly the battery and PV carries the geyser. I only run my geyser element from 10:00 to 15:00 but most days the Geyser is at 65 degrees by 12:00 this is when my pool pump comes on and run until 15:00. We also swapped our Gas/Electric oven for a full gass one.
My savings so far is around R1500 a month.
Hopefully I can buy another 8 to 10 panels and another battery before winter to run the geyser a bit longer.
 

This is a huge debate on this forum and everyone will have their own view on the matter. For me, it makes more sense to have enough PV to power everything including the geyser. Yes an EV tube geyser is more efficient, but spending that much on a geyser that can only heat water is a waste of funds, whereas using that R30k odd to add more panels is money better spent. My reasoning is that the additional power produced can be used for anything you choose. 
Like I said, everyone is entitled to their own opinion, so feel free to disagree, feel free to give me charts on how much better a solar geyser can perform on a cloudy day. It’s all a matter of what works best for you. 
 
Personally I go for more panels to produce more power that I can use wherever I need it. 😊
Someone else can comment on the inverter/battery question….