Hi 

Was wondering if anyone knows if either the Growatt or Axpert inverters can be run as Grid tied inverters and if so which models. 

I am looking for an inverter to feed into my Sunsynk as I already have 10800w of panels and would like to put some more up.

Thanks

Was thinking that using a Growatt as it may give me the option of adding some more cheap battery storage to my existing system if required as well rather than a purely Grid Tie inverter like a Solis 

In trying to decide just the following. My experience is the systems with battery power use about 600-900Wh per 24h just to power the unit. The Solis grid tied only uses about 70Wh per 24h to be ready to work when PV available. 

Hi @Sc00bs I'm not following what and why you are trying to do?

You have a 8kw sunsynk inverter with 10800 pv, how much battery storage do you already have? The sunsynk does all that you need.

 

You could add as much lithium batteries as you can afford to the 8kw sunsynk.  Let me know if I'm missing something.

 

If you are looking to increase the amount of panels then usually a Mirco inverter can be added to aux port of the sunsynk. 

@Buyeye I currently have 2 x 6kw BSL-Batt Bull Batteries & a Sunsynk 8kw with 24 x 455w PV panels

Primarily I would like more PV Panels, another 3-5kw would be handy, I understand that the limit on the grid-tie port is 5kw.

My understanding is that upgrading the existing storage on my Sunsynk would mean buying either 6kw or 5kw BSL-Batt batteries as you can't mix vendors and sometimes even battery models depending on the BMS's installed (could be wrong, not 100% sure but that is what I have been told so far)  

I am not buying any more batteries right now so the new inverter would be run as a grid- tie initially. My thought was that if it is possible to add a hybrid inverter to the grid-tie port for the extra power then it may also give me the future option to add some extra battery storage from another battery vendor. 

@Sc00bs you currently have peak of 10kw and daily production of 50kwh.

Is the need to make the peak 15kw or to make the daily production 75kwh?

at 50kwh it might make more sense to make to make your appliances more efficient. 

I'll give you my example I have a 5kw inverter with 5kw peak pv production I have moved the geyser on the inverter and and put in a smaller element than the 4kw one it came with, my problem now is that on weekends when everyone is at home we need to put things on at the same time when the geyser is on. 

So now I have 2 options, either I can increase the panels or I can reduce my peak loads even further.

Getting another growatt spf5000es(and panels)(in your case it would be another sunsynk 8kw)to parallel and another dyness powerbox F10 would mean I would probably be completely offgrid but It would cost a lot and I don't have anymore usable roof space.

So my second options is to switch to a geyser heat pump which uses 1,2kw for +-R20k. 

I'm waiting for quotes as soon as people have recovered from the riots.

So what I'm saying is that it might be cheaper to swap out the heavy appliances.

I have a Solis 4KW 4G and they are very good. Well made units and work very efficient. Easy  to install, built in DC isolator. Compliant. IP65 so can install outside if needed. CT function. Broad DC voltage input range.

 

 

 

 

2 hours ago, Buyeye said:

@Sc00bs you currently have peak of 10kw and daily production of 50kwh.

Is the need to make the peak 15kw or to make the daily production 75kwh?

 

@Buyeye I am averaging 35-38kr/hr a day at the moment, I have an East/West Split peaking at around 7.5kw. 

My initial thought was to just add an extra 8 x 455w panels, 4 on each of the strings to give me an extra 33% power, I then realised that I would be over the max DC power my inverter can handle when the sun's strength picks up again so have been looking at other options. 

Would be happy if I was making +-50kw/hr a day in winter,

Would also be interested to know what the average production difference is between Winter and Summer. 

The system has been running since April and the max I have ever got in a day is 43.80kw/hr, although I suspect that there was some clipping due to my batteries being full and my loads not being switched on intelligently enough. So I guess would have probably made closer to 50kw/hr if I had had capacity. 

I am now using node red to cycle my heavy loads so as to ensure I don't push to close to the limit. 

My monthly production for April was 992kw/hr, May 1070kw/hr & June 963kw/hr. 

 

 

 

 

4 hours ago, jlr said:

I have a Solis 4KW 4G and they are very good. Well made units and work very efficient. Easy  to install, built in DC isolator. Compliant. IP65 so can install outside if needed. CT function. Broad DC voltage input range.

 

 

 

 

Am leaning towards a 4kw Solis to give me some extra power, they seem like well made units and according to my calculations and extra 4kw will definitely be enough extra power. 

Was just considering the thought of getting something that could give me some extra power when the sun goes down if necessary/possible