Antonio de Sa

In my opinion ROI is also depended on how one runs the system, I for one only use battery for load shedding and occasionally run it for about 6 hours nighttime when my house load is about 1 Kw. I run my system on SUB and only charge the battery from PV. I don't mind using about +_ 5 Kw/h from grid on a daily basis. My average house daily consumption is +_ 21 KW/h usually 15 KW/h from solar and the remainer from grid. That amounts to +_ 150 KW/h. a month in my municipality rates on prepaid meter = R350.00. I have the data to prove it. Last three months.

I agree with you 100% in my case, after about 11:30 AM, my battery is fully charged, 200 liters 3 KW geyser done, the system goes in to idle mode, I could Easly generate +_ 10 KW/h.

@zsde My feelings exactly, the savings are the cherry on top of the cake, however, it nice to know that sooner or later we will recover the investment made to beat LS.

@Bobster. With my custom-made monitoring system, I archive everything possible from my PV, inverters and battery. I've used almost 2 MW from my battery. see dashboard of the last two years of my LBSA 5 KW battery.

@Bobster. My calculations are pretty accurate, see dashboard of the last 2 years of my system. I'm saving an average of 15 Kw/h per day, I average 21 KW/h home consumption 15 KW/h from PV and 6 KW/h from grid. I think that my ROI will be less than 5 years.

Just now, my small system 12 X 410 W panels pushing 4 KW of power from PV beautiful sunny day.

According to the above formula and based on today's price per KW, my ROI is 5,5 years. Prety much what I anticipated when decided to install solar. My estimate was 6 years. Three more years and system will be paid off. Price of system ZAR 100,000.00 Price per KW/h 2.12 Yearly consumption 6800 KW/h

@TaliaB My production today, Vaaltriangle +_ 80 Km south of JHB, 12 X 410 w Csun Panels 2 strings of 6 each 2 X 5000 KVA growat inverters, also today overcast. Peaked +_ 4 KW at 9:30

Looks like Seplos BMS.

This mount so far, had a few days with cloud edge, 6 X Csun 440 W panels per string. Prety good average, could be more as we seldom go over 3.5 Kw house consumption during day time.

In my case over and above the fact that since installation never been without power, just over two years now, the cherry on the cake is the tremendous savings, my average daily grid consumption has been around 5 Kw and 15 Kw from solar 2 X 5 KVA Growatt inverters, 12 Csun 410 W panels, 6 panels in serries to each inverter. See dashboard last 6 months. Dotted line represents overcast days.

@WannabeSolarSparky Mine are 12 X 410 W CSun panels, facing true North. 2 X 5 Kw 5000 ES Growatt inverters in parallel. 1 X 5 Kw 100 amp/hour LBSA battery. Depending on the house load I get average 16 KW of power per day, even in winter. Max, I have seen was 20 Kw when wife decided to do some baking during the day, but usually by 12 noon my system goes in to idle mode. see bellow today by 11:30 big loads done and dusted.

Mine at 10:30, heating up the 3 Kw Geyser and charging battery at very low amperage, on days like today I reduce the charging current to 12 Amps, plenty time to charge the battery, just over 85% efficiency, I have to admit, nice sunny day.

@Miguelb No idea, if I was you, I would contact LBSA and show them this, you could have a unbalanced battery or maybe some cell are not getting to full charge, my battery from day one has a cell that does not get to full charge. see dashboard. I contacted LBSA and they told me to take the battery over, I decided to live with that problem is minor and I still get SOC to 99% so I'm satisfied.

@Miguelb No, not normal at all, at 56 V you should get close to 100% SOC, maybe in the 95% 97% range, where are you taking this percentage from? at the battery display? I have a similar battery, 2 years old and I get 99% at 56 V see dashboard of my battery SOC in the last 12 hours.

My system in the Vaal Triangle, 4100 W of PV panels. dashboard the last three months, and so far this month. Not bad at all, a few cloudy and rainy days, still average 14 Kw from PV and 4 from grid. a bit bellow average my early is 15KW from PV, The dotted line indicates cloud cover.

@Miguelb Yeap, so your setting 13 is to high, you can even set it at 49 V. What is your back to utility set at?

@Miguelb I have a different inverter that is why I'm asking you what the meaning of those parameters are. My set up is as per LBSA recommended settings. Charge current they recommend 40 Amps I have mine set at 30 Amps. Charge voltage 56 V Float voltage 54 V Back to utility voltage 49 V Back to battery 50 V Cut out voltage 48 V.

@Miguelb Just a question? what is parameter 13 and 27, I think that's where your problem is. I have one of LBSA 5 Kw 100 Ah, 51.2 V running for over two years now with no issues whatsoever, with the exception of the stupid cycle count, it counts one cycle every time SOC drops below 80%.

Here is my system performance yesterday, by 10:30 AM battery fully charged, geyser done and dusted, the rest of the day what a waist.

You are 100% right, don't take a chance, do it a night when there is no PV, opening that fuse with DC on will cause. a bid DC arc flash

I think the circuit breaker next to the fuse holders will disconnect the PV, thus if he switches that breaker off, he can open the fuse holder. At least that is how my system is wired.

From your explanation the control variable is the voltage, what do you use as the derivative parameter. Do you use a PLC or a dedicated controller?

Question? where will you use the PID controller to control what part of the of the PID loop, also i would think you would need a set parameter for your PID to control. Will be the speed of the turbine or the max voltage of the MPPT.

Hello @zsde my two usually max temp around 36, see last three days.