Growatt SPF5000ES Offgrid 9kw DIY Solar Project

[Crossy]

32 minutes ago, Pink7 said:

Just got all up and running with the 2 growatts in parallel, so right now im on solar power !!!

 

The feeling of that "free" energy is infectious!!

 

[Pink7]

I dont really have sun today and tomorrow they told grid will be down 10-12 hour or so from early morning so I just grab what i can get now to charge up my batteries for tomorrow so i have to use grid for home today. Very happy to see it working..next i will get up the monitoring software on wifi so i got some more feeling on whats going on.

 

Pink

[Crossy]

2 minutes ago, Pink7 said:

I dont really have sun today and tomorrow they told grid will be down 10-12 hour or so from early morning so I just grab what i can get now to charge up my batteries for tomorrow so i have to use grid for home today. Very happy to see it working..next i will get up the monitoring software on wifi so i got some more feeling on whats going on.

 

Pink

 

Just in time methinks ???? 

 

Maybe top off the batteries from the grid overnight so everything is full when your supply goes off.

 

[TimeMachine]

9 minutes ago, Crossy said:

 

The feeling of that "free" energy is infectious!!

 

Not yet. Got many years of nervous wait to see if equipment fails over the payback period. Real free is when you just tie into your streets overhanging wires. Had a chance to buy a condo that had balcony with street wires within hands length. Could easily wire a coil around the main Street line to get free power. But the idea of staring at cables didn't suit me. Also brings the topic of how ugly street views are if rooftops with square black tiles in view. Does that bother anyone. Did , me at first, but then just seems to be part of a normal roof nowadays.

 

[Pink7]

8 minutes ago, Crossy said:

 

Just in time methinks ???? 

 

Maybe top off the batteries from the grid overnight so everything is full when your supply goes off.

 

Im currently charge at around 20Amp per battery from the "sun"

 

Pink

[Crossy]

15 minutes ago, Pink7 said:

Im currently charge at around 20Amp per battery from the "sun"

 

Yeah, wait until the sun goes to bed and top-off from the grid.

[Fruit Trader]

1 hour ago, TimeMachine said:

Not yet. Got many years of nervous wait to see if equipment fails over the payback period.

Not everyone is nervous, for some; DIY solar is a hobby and take ROI far less seriously.

 

I on the other hand closely monitor the returns from solar systems parked on packaging sheds owned by my Thai family.

 

It is of course wrong to claim solar is powering your home at no cost before payback is achieved. Towards the end of the day when work consumption drops off, our electric lift truck grabs a tiny amount of solar power but I never claim its surplus and free from cost. 

 

[MJCM]

1 hour ago, Fruit Trader said:

Not everyone is nervous, for some; DIY solar is a hobby and take ROI far less seriously.

+1

Absolutely in our case I never cared about the ROI when I started thinking about Solar, the Wife did at first, but that said since the beginning we have grown from a Simple GTI (3 panels) that just feeds energy back into the grid to a On-Grid Sofar 5kW Inverter with 10 Panels and producing enough to supply the house with electricity and the left over is feed back in to the grid. (But have to limit the feed-in drastically (currently at 0.5kW) because of the danger of going into negative territory ???? 

Next step (future) is Hybrid Inverters (2x 5kW) and a ESS of around 30kW (but want to start with around 10kW at first)

 

[Pink7]

3 hours ago, Crossy said:

 

Just in time methinks ???? 

 

Maybe top off the batteries from the grid overnight so everything is full when your supply goes off.

 

I got the news early this morning. Then i decided To get this finish and up as soon as possible, so I skipped breakfast and started right away.????

 

Pink

[MJCM]

1 minute ago, Pink7 said:

I got the news early this morning. Then i decided To get this finish and up as soon as possible, so I skipped breakfast and started right away.????

 

Pink

????

And how is it holding up thus far?

[Pink7]

3 hours ago, TimeMachine said:

Not yet. Got many years of nervous wait to see if equipment fails over the payback period. Real free is when you just tie into your streets overhanging wires. Had a chance to buy a condo that had balcony with street wires within hands length. Could easily wire a coil around the main Street line to get free power. But the idea of staring at cables didn't suit me. Also brings the topic of how ugly street views are if rooftops with square black tiles in view. Does that bother anyone. Did , me at first, but then just seems to be part of a normal roof nowadays.

 

I was seduced many times when planing and buying with some cheaper options but I tried to choose good value (Good quality at good price) With the hope that It will last for many years but time will show. I tried to plan the setup to have some extra margins for the capacity on for example inverter. But time will show.. I spent more or less exact 300k for all. Electric bill lately been around B 4k (+/- 500) so maybe 6-7 years needed for ROI.

 

Pink

[Pink7]

6 minutes ago, MJCM said:

????

And how is it holding up thus far?

All was up and running at lunchtime but because of the weather and my batteries needed to be charged I turned off AC Out on the inverters. I only tested 15 minutes or so today offline from grid.

 

Pink

[MJCM]

5 minutes ago, Pink7 said:

spent more or less exact 300k for all

That is an advantage of being able to do it do yourself and not leaving you in the hands of a installer

 

 

 

[Pink7]

17 minutes ago, MJCM said:

That is an advantage of being able to do it do yourself and not leaving you in the hands of a installer

 

 

 

Yes, It also a plus to have planed and build it so it can be managed and fixed as much as possible by myself.

 

Pink

[Pink7]

So i was sure to wake up early today to get some charge before grid was taken down ( will be down whole day) So i started up charge from solar as soon there was some sign of daylights but that was very optimistic from a solar beginner. I had to wait an hour or some before see and sign on charge from the solar.

 

Now grid is down and i have got up my wifi monitoring on the master inverter. I have not figured out yet if it show data from master only or master and slave inverter together.

 

Pink

[Muhendis]

10 minutes ago, Pink7 said:

Now grid is down and i have got up my wifi monitoring on the master inverter. I have not figured out yet if it show data from master only or master and slave inverter together.

Does it really matter?

If things work when you switch 'em on You have achieved success.

Well done.

[Pink7]

12 minutes ago, Muhendis said:

Does it really matter?

If things work when you switch 'em on You have achieved success.

Well done.

I must admit Im curious to see if if will produce around what i expected and calculated it to do. Things seems to run a bit low for now.. I get less than 10A charge currently

 

Pink

[Pink7]

So i have adjusted the charge voltage some up. Actual charge voltage is some lower than what in the settings on the inverter. Currently charge at 50A or so now who is much better.

 

Pink

[Pink7]

Now i understand why active balancing only at the end of the charge is discussed. I had set my JK BMS to start balance from dc 3.45v as in this video but ended up with deviation of dc 0.2xx v who took much time to get balanced back and I feel it messed up the charge process and I also guess its ineffective. Now i have change my settings and try balance from  dc 3.3v tomorrow. Lets hope thats a better and smoother way of charge.

 

 

 

Pink

[Pink7]

Today fist full day with all set up as it should be to work normally. Total  generated today is 24 kvh. Its funny how carefully Im with the usage of electric now when its "free"

 

 

Pink

[Muhendis]

8 hours ago, Pink7 said:

Today fist full day with all set up as it should be to work normally. Total  generated today is 24 kvh. Its funny how carefully Im with the usage of electric now when its "free"

 

 

Pink

Excuse me pointing out this slight discrepancy, but  I think when you write kvh (kilo volt hours) you really mean kwh (kilo watt hours).

[Pink7]

2 minutes ago, Muhendis said:

Excuse me pointing out this slight discrepancy, but  I think when you write kvh (kilo volt hours) you really mean kwh (kilo watt hours).

You correct. My mistake.

 

Pink

 

[Muhendis]

9 hours ago, Pink7 said:

Today fist full day with all set up as it should be to work normally. Total  generated today is 24 kvh. Its funny how carefully Im with the usage of electric now when its "free"

 

 

Pink

Free at the point of use and aware of the limitations. 

Yes when using PEA we tend to do what we like with it without a thought for it's seemingly bottomless pit of available power.

As soon as we start producing our own electricity, we become very aware of our power usage and tend to keep a more critical eye on things switched on.. 

[lom]

21 hours ago, Pink7 said:

Now i understand why active balancing only at the end of the charge is discussed. I had set my JK BMS to start balance from dc 3.45v as in this video but ended up with deviation of dc 0.2xx v who took much time to get balanced back and I feel it messed up the charge process and I also guess its ineffective. Now i have change my settings and try balance from  dc 3.3v tomorrow. Lets hope thats a better and smoother way of charge.

 

Most important is to not balance while charging. A balancers algorithm is based on measuring cell voltages which must be quite stable or the algorithm fails. Cell voltages are not stable enough during charging, they vary a lot.

[Pink7]

One more day with charging. My growatt and JK BMS show batteries full just before lunchtime. This 2 days i wake up to around 50-60 A left battery capacity. It seems that some batteries not easy to get over 3.35v but im not sure if thats even needed? After some balancing it look like 3.3x v per cell. 277 amp. 99% capacity is the standard i can expect. When balancing  over3.3 look like its 80% done by de-charge who is higher  and very less added to lowest batteries. So 55.x will end up with 53.x when finish balancing.

 

 

 

Pink

 

 

[Pink7]

36 minutes ago, lom said:

Most important is to not balance while charging. A balancers algorithm is based on measuring cell voltages which must be quite stable or the algorithm fails. Cell voltages are not stable enough during charging, they vary a lot.

I see some of my batteries not easy to charge over 3.35 or so I guess the new settings on 3.30 as starting level was better but maybe 3.35 will be better from what i see from my batteries.

 

Pink

[Crossy]

Google "DIY solar forum" or link from one of Will Prowse's videos, loads of JK BMS setup info.

 

[Pink7]

16 minutes ago, Crossy said:

Google "DIY solar forum" or link from one of Will Prowse's videos, loads of JK BMS setup info.

 

I have watched quite a few and I think the setup is ok. The question is if its normal or not for the batteries to struggle to get over 3.35v? Capacity wise it seems ok..

 

Pink

[lom]

17 minutes ago, Pink7 said:

The question is if its normal or not for the batteries to struggle to get over 3.35v?

3.35V (53.6V)  is 100% SOC (at least on my batteries)  they are currently at 53.1V or 97% SOC but I have also seen them at 55.2V. 

I'm using Seplos BMS's which are set for a max charging voltage of 57.6V which the BMS has told my Deye inverter to provide. Maybe you need to raise the charging voltage?

Anyway, don't charge or discharge when balancing, it takes forever to get balance if the there is additional current flowing through the cells when balancing. 

Your JK BMS has a good balancer compared to the ones (passive, low current) in my Seplos BMS's.

[Pink7]

12 minutes ago, lom said:

3.35V (53.6V)  is 100% SOC (at least on my batteries)  they are currently at 53.1V or 97% SOC but I have also seen them at 55.2V. 

I'm using Seplos BMS's which are set for a max charging voltage of 57.6V which the BMS has told my Deye inverter to provide. Maybe you need to raise the charging voltage?

Anyway, don't charge or discharge when balancing, it takes forever to get balance if the there is additional current flowing through the cells when balancing. 

Your JK BMS has a good balancer compared to the ones (passive, low current) in my Seplos BMS's.

Thanks for that info.. I got same 100% SOC on 3.35 so all is fine then. I also want to be moderate on charge and battery voltage so then all fine.

 

Pink