Hi There Guys, 

Just have my solar setup now for a week... 

I have the following components installed:

• Deye 5 kw Hybrid Inverter
• 1 x Dyness Battery Lithium Ion 5.12KWH 51.2V 100Ah
• 8 x Seraphim 560W 144 Cell SIV Series Solar Panels
• Installed in KZN

So I only realized after installation that I can only use about 50% of the battery wattage since its a 0.5c... Which sucks but I understand why that is the case. 
I also only realized after installation that the Solar panels rating is not the rating I would achieve under normal conditions.

I did not have a great roof that was North Facing that I could use so I initially got all 8 Panels installed on a SE facing roof (Pic attached) which gets the morning sun quite nicely. 

After doing that I noticed that my chimney would cast a shadow over 1 whole panel at about 1:30pm which caused the production to take a big knock... (Pics attached)

My installer was quite helpful and came over the weekend to move the panels. I now have 4 on the SE side away from the Chimney shadow and 4 on a NW facing roof.  
All 8 are still on 1 string.

Roof pic attached. (The circled side shows the SE side)
The second Pic shows two red markings for the current 4 & 4 panels placement.

So the normal power generation for each panel says ~422w... 

I am generating a peak of about 2.24kW at about 11:30am today. Its a nice clear sunny day. 

I cant help but feel a little disappointed with the peak production...
Is this good production power for this time of year with my setup? Considering that under normal operation I should see > 3kW of production? 
Wondering how it will perform in Summer? 
Does installing 4 on SE and 4 on NW reduce production a lot?
Will I need to add more Panels at some point?

Sorry for all the questions... 

Please let me know if I've left out any info that you may need to provide more informed answers?

Many thanks 

My instinct tells me the 2 different directions should be on 2 separate strings, one in each of the MPPTs. I don't suppose you could build a frame facing north?

While there are situations having 2 strings (facing opposing directions - more so East/West) on 1 mppt can be beneficial this would be more the case of parallel.

The way it is now all being 1 string, that shading on 1 side will severely hinder productivity.

Easy fix would be split to separate inputs.

Ideally you would reorient the SE facing panels more N facing. They would not be very productive at all facing southerly.

3 hours ago, Garthox said:

While there are situations having 2 strings (facing opposing directions - more so East/West) on 1 mppt can be beneficial this would be more the case of parallel.

The way it is now all being 1 string, that shading on 1 side will severely hinder productivity.

Easy fix would be split to separate inputs.

Ideally you would reorient the SE facing panels more N facing. They would not be very productive at all facing southerly.

Spot on with the S? panels.

@Garthox 

@cybernetics777

Rather sacrifice the morning sun on the SE string and place all 8 in one string facing NW for the best production based on your roof as I understand from your pictures.

 

Edited July 31, 20233 yr by Scorp007

ok cool. that makes sense.
I do have an awning that I recently put on (pic attached) where I could possibly build a frame that will face North...  and move the 4 x SE facing panels onto that. 
It will save a lot in DC cable as well since the Inverter is just under the Awning.

In the pic attached you can see the 4 x NW facing panels about to get hit by some shade now (2pm) (neighbors tree)

3 hours ago, cybernetics777 said:

I am generating a peak of about 2.24kW at about 11:30am today. Its a nice clear sunny day. 

Hmmm... I don't think that's that good, though there are variables IE your latitude and the angle of your panels. The angle at which your panels works best varies with the time of year. IOW, your panels are at the perfect angle only twice a year.

BUT you have potentially 4.48kW of PV. I have 6 panels facing NNW and 6 facing ENE. These are on separate strings. My total theoretical PV is 3.9Kw. My peak production is usually round about 11:30. At 11:05 today I was producing 3.09kW, then the battery was fully charged and the system drew just enough PV to service loads. But the loads went up again at 12:00 and I can tell you that 12:40 I could still get 2.7kW from the panels, and at 13:15 2.36kW. 

I was able to get 80% of theoretical capacity (maybe a bit more), whilst you got about 50%. So I think you could do a bit better, even given the variables we discussed.

South-ish facing is never going to work that well in South Africa, but I wonder if you won't do better just splitting this into two strings. That way you won't have 4 underperforming panels pulling the other four down.

I don't have a lot of north facing roof (none in fact, but NNW is close enough) and I wonder if you can't fit 4 panels onto your NNEish facing roof. Look at mine

You want some tilt on them... In Gauteng, in the summer, you can have them nearly flat, but in the winter when the sun is lower, you want the tilt, probably more than I actually have. So go for some tilt and accept that they will not be optimal mid-summer or mid-winter, but you are not losing as much in the winter.
 

Edited July 31, 20233 yr by Bobster.

I could prob fit 4 on my NNE facing roof but then I would be using a lot of cable... 
Would the gains I can expect from that be diminished too much by cable length? 

 

3 minutes ago, cybernetics777 said:

I could prob fit 4 on my NNE facing roof but then I would be using a lot of cable... 
Would the gains I can expect from that be diminished too much by cable length? 

 

I don't have the technical knowledge to answer that. But my inverter isn't under either of my strings, and the run from the ENE string must be quite long. 

But most of all you need sun on the things. My ENE panel isn't in the originally planned location. That's because I agreed with the installer that after we shook hands on the deal but before he started putting in the hardware, I'd go and look to see which parts of the roof were getting plenty of sun.

If you have a drone you can take photos at different times of day. If that NNE facing roof gets a lot of shade then you start thinking again.

Edited July 31, 20233 yr by Bobster.

yes. my other option would be to build a frame onto the Awning... fit the 4 panels there and ask politely to chop down my neighbours tree that blocks the sun from about 2pm now in winter. That way I would also use very very little cable.

1 hour ago, cybernetics777 said:

yes. my other option would be to build a frame onto the Awning... fit the 4 panels there and ask politely to chop down my neighbours tree that blocks the sun from about 2pm now in winter. That way I would also use very very little cable.

Why are you soo worried about how much cable you are using? Is it the voltage drop you are worried about?
How long are your runs of cable and I am assuming you are using 4mm cable?

 

Ask your neighbour nicely if you could cut down, or at least trim, the tree - although I feel you'd need to cover the costs and your neighbour may not be happy cutting the tree down - so trimming may be a better option. Depending on your usage and needs, it may be best to add more panels although with that being said you need to get your current panels performing as they should and maximize on those and ensure you know where you will be adding the additional panels for best maximum performance and yield.

@PsyCLown yeah my worry is that I would loose some production power though the length of the cables. 

Definitely not more than 50m worth of cable. Between 30 and 50m probably. Do you think that would loose much?

Yeah Il be happy to cover the cost to trim it down... the same tree is actually starting to pull on my fibre line as well. 

34 minutes ago, cybernetics777 said:

@PsyCLown yeah my worry is that I would loose some production power though the length of the cables. 

Definitely not more than 50m worth of cable. Between 30 and 50m probably. Do you think that would loose much?

Yeah Il be happy to cover the cost to trim it down... the same tree is actually starting to pull on my fibre line as well. 

Yes any length of cable we loose power. Running 50m of 4mm cable could loose 5% or 6V at a 10A current. You could end up far worse and loose 25% of PV power having shade or a direction with lower irradiance. 

As to knowing where and what extend of shade can easily be done with a phone and camera APP that takes pics every say 15min. 

Edited July 31, 20233 yr by Scorp007

17 hours ago, Scorp007 said:

Yes any length of cable we loose power. Running 50m of 4mm cable could loose 5% or 6V at a 10A current. You could end up far worse and loose 25% of PV power having shade or a direction with lower irradiance. 

As to knowing where and what extend of shade can easily be done with a phone and camera APP that takes pics every say 15min. 

Precisely this, the shading is far more of a concern than the voltage drop. 6v at 10A is only 60W. Not a significant amount I feel.

If you go for larger 6mm cable, there should be less voltage drop - although I don't feel the costs will justify the exercise.

 

Here is a nice voltage drop calculator if you want to see what to expect: https://midsummerenergy.co.uk/voltage-drop-calculator

9 minutes ago, PsyCLown said:

Precisely this, the shading is far more of a concern than the voltage drop. 6v at 10A is only 60W. Not a significant amount I feel.

If you go for larger 6mm cable, there should be less voltage drop - although I don't feel the costs will justify the exercise.

 

Here is a nice voltage drop calculator if you want to see what to expect: https://midsummerenergy.co.uk/voltage-drop-calculator

Thanks for the link. Great to see they indicate how to use the distance/length. 

I see my calc used 50m one way and perhaps it should have been 25. So the loss is much lower. 

My call. Stick to 4mm cable. 

Thanks for the info guys. 

I have decided to build a frame over the awning to hold 4 panels. 

 

Then the other 4 on a N facing roof I have which should be about 35m of cable. 

 

From the info you guys have provided I think this is the best route. 

 

My neighbor has given me permission to trim the trees down. So I think that will be a big plus for the afternoon time until like 4pm. 

 

Il post some stats after the change is done. Should be a few weeks or so. 

I feel like this is going to make them perform optimally now. 

Thank you guys. 

Edited August 1, 20233 yr by cybernetics777

Hi Guys, 

I've finally completed the moving of the panels and I am glad to report that facing them North has made a HUGE difference. 

Just to Reiterate... 

I have 8 x 560w Seraphim Panels. 

I've moved 4 to a North Facing roof about 35m away from the inverter. (PV2) I do loose a little bit of production here... I guess this is because of the cable length. 

I've moved 4 onto a North Facing frame just above the inverter. (PV1)

 

Pics for stats attached. These were taken now... 09:58.