Growatt SPF5000ES Offgrid 9kw DIY Solar Project

[Pink7]

After some long research it was time to get this solar project started. Today i ordered 11x 330 Sunergy Poly at B2990. I could not resist this offer, best deal i see in long time, Waiting for delivery tomorrow. 

 

Pink

 

 

[Encid]

47 minutes ago, Pink7 said:

Today i ordered 11x 330 Sunergy Poly at B2990

That's a really good price!

 

Here's the current online price from Global House... 

 

[Crossy]

Yeah @Encid I'm seeing that price too ???? 

 

Must be a local offer.

[Encid]

1 minute ago, Crossy said:

Must be a local offer.

Runout sale?

Making way for new stock?

 

Well done @Pink7... you got yourself a bargain 

[Encid]

1 hour ago, Pink7 said:

Today i ordered 11x 330 Sunergy Poly

So using Crossy's formula... 330W x .8 efficiency x 5 hours production x 11 panels = 14.52 kW of forecast average daily production (dependent of course on many variables). 

 

Right @Crossy?

 

[Crossy]

2 minutes ago, Encid said:

So using Crossy's formula... 330W x .8 efficiency x 5 hours production x 11 panels = 14.52 kW of forecast average daily production (dependent of course on may variables). 

 

Right @Crossy?

 

Sounds about the right ballpark.

[Pink7]

It was a local offer they was selling out some stock, it was less than 20 panels before i got my 11 panels. Im very happy with the deal..

 

Pink

[Pink7]

8 minutes ago, Encid said:

So using Crossy's formula... 330W x .8 efficiency x 5 hours production x 11 panels = 14.52 kW of forecast average daily production (dependent of course on many variables). 

 

Right @Crossy?

 

Thanks for that info.. It should be near 50% of my usage then. I use 1000 unit per month, or 33kw per day

 

Pink

[sezze]

2 hours ago, Encid said:

So using Crossy's formula... 330W x .8 efficiency x 5 hours production x 11 panels = 14.52 kW of forecast average daily production (dependent of course on many variables). 

 

Right @Crossy?

 

Make the formula much easier ... installed power  X 4 . In this case its 3630 watt (11 x 330) X 4 = 14.55 kWh .

[Crossy]

8 hours ago, sezze said:

Make the formula much easier ... installed power  X 4 . In this case its 3630 watt (11 x 330) X 4 = 14.55 kWh .

 

Yeah, I leave it split as Watts and Hours simply to help people understand the units, it's already a terrible over-simplification anyway. ????  

[Pink7]

Got my panels today delivered from Global and all looked good. Still thinking what inverter to go for. Last days i see there is a new Easun/Powland 5.6KW hybrid inverter at 17300TB with wifi and Parallel. The Mppsolar 8kv is now  USD 1210 + some watt. From what i have read its migh not very much difference between Mpp solar units and Powmr, easun, powland etc. ( i readed they all made by same company)

 

Pink  

[Crossy]

I still recommend that you get sufficient inverter power for your "ultimate" configuration even if you don't have all your panels and storage (the expensive bit) yet.

 

At least then you know that your inverters will indeed run in parallel. There's no guarantee that a future version of the same unit will pair with your existing one.

 

[Pink7]

20 minutes ago, Crossy said:

I still recommend that you get sufficient inverter power for your "ultimate" configuration even if you don't have all your panels and storage (the expensive bit) yet.

 

At least then you know that your inverters will indeed run in parallel. There's no guarantee that a future version of the same unit will pair with your existing one.

 

Yes i guess thats the smartest to do.. Whats your view on mpp solar 8kv vs 2 x5.6kw easun?

 

Pink

[Crossy]

18 minutes ago, Pink7 said:

Yes i guess thats the smartest to do.. Whats your view on mpp solar 8kv vs 2 x5.6kw easun?

 

MPP are a reasonably well-known low-cost brand, not so sure about the Easun.

 

11.2kW vs 8kW and having two units means that if one fails you still have power. Of course having two units also affects the reliability so there's actually more chance of having a unit fail.

 

If I could get 2 x 5kW MPP units there would be no argument ???? 

 

[Pink7]

1 hour ago, Crossy said:

 

MPP are a reasonably well-known low-cost brand, not so sure about the Easun.

 

11.2kW vs 8kW and having two units means that if one fails you still have power. Of course having two units also affects the reliability so there's actually more chance of having a unit fail.

 

If I could get 2 x 5kW MPP units there would be no argument ???? 

 

You have some good points there. If i get the MAX series 8KW 48Vdc :

 

current solar panels: 330 x 11 = 3630

Then if future solar panels same : 330 x 11 = 3630

And my daily usage is average 35kw. The charger is 120A. So if i have 6 solar hours per day i would need around 75% of my usage in usable battery power? 25kw or so.. 120A charger handle that?

 

Pink

[Crossy]

14 minutes ago, Pink7 said:

You have some good points there. If i get the MAX series 8KW 48Vdc :

 

current solar panels: 330 x 11 = 3630

Then if future solar panels same : 330 x 11 = 3630

And my daily usage is average 35kw. The charger is 120A. So if i have 6 solar hours per day i would need around 75% of my usage in usable battery power? 25kw or so.. 120A charger handle that?

 

Pink

 

With that much storage I think you'll need more charger. So 2 x smaller inverters might be better.

 

Our 50A charger puts around 9kWh into our pack by about 1PM, earlier on a good day.

 

Today's charge profile, a bit dull.

 

.

[Pink7]

Well im not sure at all about that much storage.. Thats why step1 and 2 is just solar and grid first, then step 2 batteries who match the current panels capacity. maybe 12kw or something? from 12kw i should get 6kw usable power?

 

I dont need to get 100% power from solar, just want to try figure out a estimate for future setup to ad up with what i buy now.

 

Pink

[Crossy]

I'd definitely ensure you have enough charger for your max storage.

 

EDIT although if you are sure you have enough inverter you can add separate MPPT charge controllers.

[Pink7]

4 minutes ago, Crossy said:

I'd definitely ensure you have enough charger for your max storage.

 

Yes, i just did a basic calculation:

Mpp: 125A x 6 hours converted to watt:  Just over 15KW

2 x Easun: 2 x 100A x 6 hours to watt;  Just over 26Kw

 

Pink

[Pink7]

7 hours ago, Crossy said:

 

If I could get 2 x 5kW MPP units there would be no argument ???? 

 

The 5kW MPP have a lover limit of max solar voltage (450v) 

 

Btw i just noticed the VDC was discussed in the old  tread and was said to be 45voc but its 45.5voc. So 500.5vdc with a max 500VDC inverter ??

 

Pink

[Crossy]

8 hours ago, Pink7 said:

The 5kW MPP have a lover limit of max solar voltage (450v) 

Btw i just noticed the VDC was discussed in the old  tread and was said to be 45voc but its 45.5voc. So 500.5vdc with a max 500VDC inverter ??

Pink

 

I wouldn't go much over 90% of the maximum input voltage of the MPPT, 10 panels would be 455V nicely in the green.

 

Definitely 500.5V on a max rated input of 500V would be classed as "unwise", it might be OK or it might go fzzzt on a cool morning when the panels are generating just a smidge more oomph.

 

The problem is the panels come up to voltage very quickly when it gets light but there's not much energy available so the inverter doesn't do much leaving the full Voc on the inputs.

[007 RED]

4 hours ago, Crossy said:

 

The problem is the panels come up to voltage very quickly when it gets light but there's not much energy available so the inverter doesn't do much leaving the full Voc on the inputs.

Just to illustrate the point that @Crossy has made above.  The graph below shows the voltage and current output from my small scale system (4 x 415W panels) taken a few minutes ago.  Yesterday at about 12:30pm, the voltage was about the same, but the current had risen to 10A thus producing about 10kW.

[Pink7]

47 minutes ago, 007 RED said:

Just to illustrate the point that @Crossy has made above.  The graph below shows the voltage and current output from my small scale system (4 x 415W panels) taken a few minutes ago.  Yesterday at about 12:30pm, the voltage was about the same, but the current had risen to 10A thus producing about 10kW.

Thanks for that info.. I change the plan to 10 panels on the inverter. How you pull this data from your system? you use phone or pc?

 

Pink

 

[Pink7]

UPDATED PLAN:

 

After some more discussions and info here in the forum i did some changes on the plan: I called Global and ordered 9 more of the 330w panels, so i will have a final setup with 330 x 10 panels x2. Most probably with 2 x 5xxx kw in parallel. The final setup the would need around 800A batteries (400A usable)

 

Here is something not clear for me: When parallel 2 inverter i see the illustrations show AC IN shared too the 2  inverters and AC OUT combined to load. What do i need for this to get them secured shared/combined? Can the 2 x AC OUT be combined together in the breaker box?

 

Pink

 

 

[BritManToo]

26 minutes ago, Pink7 said:

The final setup the would need around 800A batteries (400A usable)

Doesn't mean anything to me, battery storage is measured in kWhr.

Here is a 48V 8kWhr battery, 35kbht.

https://www.lazada.co.th//products/i2393934477-s8157207174.html

 

80-90% of Lifepo4 batteries are usable, nobody buys lead acid batteries any more.

[Pink7]

39 minutes ago, BritManToo said:

Doesn't mean anything to me, battery storage is measured in kWhr.

Here is a 48V 8kWhr battery, 35kbht.

https://www.lazada.co.th//products/i2393934477-s8157207174.html

 

80-90% of Lifepo4 batteries are usable, nobody buys lead acid batteries any more.

Your right thanks.. i was writing A instead of wats..i will need a max of 20kw/day from batteries.  80-90 % was better, 

 

Pink

[Crossy]

2 hours ago, Pink7 said:

Here is something not clear for me: When parallel 2 inverter i see the illustrations show AC IN shared too the 2  inverters and AC OUT combined to load. What do i need for this to get them secured shared/combined? Can the 2 x AC OUT be combined together in the breaker box?

 

Yes, but do ensure you place breakers and fuses where the installation manual says.

 

[007 RED]

3 hours ago, Pink7 said:

Thanks for that info.. I change the plan to 10 panels on the inverter. How you pull this data from your system? you use phone or pc?

 

Pink

 

My 2kW Sofar GTI came with plug-in Wifi module which enables the inverter to send a fairly comprehensive range of performance data to a remote server (in China) via my router.   It appears that the remote server 'calls' for data from the inverter about every 5 minutes.

 

I can access the inverter's data through either an application on my phone or on my PC.  The 2 apps provide slightly different outputs and are very easy to use.  The mobile app is fairly basic, whereas the PC is very comprehensive with a wide range of visual and numerical outputs, some of which can be modified to suite your needs.  The PC version also allows me to download all the system data into an Excel spreadsheet which I can, if required, produce various graphs etc. to meet my needs.

 

FYI... Both apps are recommended by the inverter manufacturer (Sofar).  The PC app = "SOLAMAN" and the mobile app = "SOLAMAN SMART"

 

NOTE:  The monitoring facility does not provide information on the performance of individual panels, it only provides data on the overall output performance of the array.

 

I hope this helps.

[Pink7]

Tried another calculation to see what battery/charger i can handle with the setup:

 

Production estimate: 330w x 20 x 0.8 is estimated average around 5300wh

Usage estimate: 1000kw/month  around 1500wh

Left production for charge: 5300wh - 1500wh = 3800 wh 

Daily production capacity for charge : 3800wh x 5 hours/day =19kw

Charge capacity: 3800wh equals 79A 48v

Battery capacity volume: 24kw x 80% usable = 19.2kw

Battery capacity amp: 500amph/48v maybe not a common size so might go with 400amp.

 

If i got something wrong pls let me know

 

Pink

[Encid]

2 hours ago, Pink7 said:

Production estimate: 330w x 20 x 0.8 is estimated average around 5300wh

The estimate should be based on panel rating x 0.8 x 5 (80% of panel rating over 5 hours), so if you have 20 off 330W panels your average daily production would be 330 x 20 x 0.8 x 5 = 26.4 kW.