Stringing in an East-West orientation of Solar Panels

[TheElectrician]

Hey Guys,

I understand that while designing an East-West (Dual-Tilt) system, I will have to string all the East modules together and similarly all the west modules together because the production on the East is more during the morning than the west and vice versa to get a better overall production. Am I doing this correct? Or is there a better stringing method?

Thanks

[ggunn]

Hey Guys,

I understand that while designing an East-West (Dual-Tilt) system, I will have to string all the East modules together and similarly all the west modules together because the production on the East is more during the morning than the west and vice versa to get a better overall production. Am I doing this correct? Or is there a better stringing method?

Thanks

That's the way to do it, yes.

[TheElectrician]

That's the way to do it, yes.

Thanks ggunn!

[Zee]

assuming it is strictly panels...... no optimizers, or other panel level electronics

[TheElectrician]

assuming it is strictly panels...... no optimizers, or other panel level electronics

Yes, It is strictly panels, but good thinking, so, what will be the difference in stringing if I use optimizers like SolarEdge Optimizers for every 2 panels? Should each optimizer be placed for an East and a West module to account for shading on the West module in the morning and the shading of East in the evening or East-East module like I mentioned in my OP.

[ggunn]

Yes, It is strictly panels, but good thinking, so, what will be the difference in stringing if I use optimizers like SolarEdge Optimizers for every 2 panels? Should each optimizer be placed for an East and a West module to account for shading on the West module in the morning and the shading of East in the evening or East-East module like I mentioned in my OP.

You don't want to put an E facing and a W facing module on the same optimizer but you can put E facing and W facing modules on the same string.

[Zee]

Yes, It is strictly panels, but good thinking, so, what will be the difference in stringing if I use optimizers like SolarEdge Optimizers for every 2 panels? Should each optimizer be placed for an East and a West module to account for shading on the West module in the morning and the shading of East in the evening or East-East module like I mentioned in my OP.

I am not aware of optimizers that work for more than one panel per optimizer. Doesn't mean they don't exist, I simply only know residential where that is the norm.

Assuming one optimizer per panel..... you can string pretty much any east and west panels together (Including just east or just west together).

I wouldn't think optimizers would boost power more than 1-2% in strings facing same direction and mostly un-shaded. Others may have exact stats.

Not sure it is worth adding cost and complexity and failure points for above. Then again, it would add excellent panel level monitoring....... So, i dunno.

For rapid shutdown, however, it may well be worth it.

[Carultch]

I am not aware of optimizers that work for more than one panel per optimizer. Doesn't mean they don't exist, I simply only know residential where that is the norm.

In some commercial applications, particularly the ones that involve the inverters outputting 277/480, not only do you get to do that, you might have to do that to achieve your desired DC capacity. The deal is, you're limited to 30 in series for the shutdown voltage to not exceed 690.12's limit, due to the default 1V/optimizer output.

You don't want to put an E facing and a W facing module on the same optimizer.

It used to be the case that most dual module optimizers involved series connecting the modules. Now with the onset of the 2019 rule, limiting you to 80V within the array, the newest version of dual module optimizers are built for parallel inputs instead of series inputs.

Given that voltage is most sensitive to temperature rather than irradiance, it is less of a loss to connect dissimilarly oriented modules in parallel, than it otherwise would be for modules in series. Current is more sensitive to irradiance, which means all modules may operate as if they received the lowest irradiance among the ones in series. More advisible to parallel different orientations, than to series different orientations.

Once you have separate power processing zones (which optimizers are), the respective modules/groups of modules operate independently anyway.

[jaggedben]

In some commercial applications, particularly the ones that involve the inverters outputting 277/480, not only do you get to do that, you might have to do that to achieve your desired DC capacity. The deal is, you're limited to 30 in series for the shutdown voltage to not exceed 690.12's limit, due to the default 1V/optimizer output.


It used to be the case that most dual module optimizers involved series connecting the modules. Now with the onset of the 2019 rule, limiting you to 80V within the array, the newest version of dual module optimizers are built for parallel inputs instead of series inputs.

Given that voltage is most sensitive to temperature rather than irradiance, it is less of a loss to connect dissimilarly oriented modules in parallel, than it otherwise would be for modules in series. Current is more sensitive to irradiance, which means all modules may operate as if they received the lowest irradiance among the ones in series. More advisible to parallel different orientations, than to series different orientations.

Once you have separate power processing zones (which optimizers are), the respective modules/groups of modules operate independently anyway.

Do the latest 2-module optimizers have two MPPTs then?