East West Arrangement simulation in PVsyst.

[Mike]

I have a roof of 1000m2, and i propose an east west technique for the PV system design.

Please review below steps and provide your feedback if the input data of such simulation is correct or not?

I presume to simulate such system in PVsyst. the following steps I have considered.

I have introduced 2 orientations 

a)1st to east and with area (500m2)

• I have chosen the module power and quantities based on the efficient usage of the available area (maximum percentage used of the available 500m2)
• I have chosen the inverter power rating 20% less than total modules power rating.

b)2nd to west and with the same area (500m2) with single inverter

• I have chosen the module power and quantities based on the efficient usage of the available area (maximum percentage used of the available 500m2)
• I have chosen the inverter power rating 20% less than total modules power rating.

[Michele Oliosi]

For the implementation within PVsyst:
Are you in a dome (e.g. schematically /\/\/\/\/\/\/\/\/\ ) or two pane roof (schematically //////   \\\\\\\ ) situation ?

• For the dome one, you could just use a single sub-array, and choose "mixed orientation 1 and 2" instead of having two separate orientation sub-arrays.
• For the two pane roof, I think your approach works well: you create one sub-array for each orientation individually.

[Mike]

I have an upper roof and lower roof (tilt angle is zero) - (Flat roofs). So, I believe single Sub-array with "mixed orientation 1 and 2" for each roof would be suitable.

Also, I am planning to have either (one inverter per each orientation, so total no. of inverters would be four (two for the upper roof and two for the lower roof)), or (one inverter for each roof with 2 MPPT). 

What do you think for the above design strategy? 

[dtarin]

If tilt is zero, you dont need to consider mixed orientations. Just create two subarrays, each with 2 inverters, and the number of modules/strings per roof for each. 

[Michele Oliosi]

Yes, I agree with @dtarin if your modules lay flat, then you can put everything in a single orientation.
If the modules are in alternating east west fashion (what I meant by domes i.e. something like the image below), then mixed orientation for each subarray is fine.