PVsyst horizon file

[george]

Hello,

I have a PV SOL 6.0 horizon file. I uploaded it in here (your attachment does not allow attaching .hor filetypes).

I need to send this file to a person who is using PVsyst (I still haven't asked which version does he have).

The problem is there seems to be some tiny difference between PVsyst and PV SOL .hor files.

How can I edit my PV SOL .hor file, so that it can be imported into PVsyst?

I took a look at your PVsyst v6 help page, and it says that PVsyst 4, in its .hor files used only azimuths from -120 to 120.

But with PVsyst 5, the -180 to 180 azimuths are supported, but the number of azimuths has been reduced from 240 in PVsyst to 120 in PVsyst 5. Did I understand this correctly?

Can somebody please show me how can I convert my PV SOL .hor file to PVsyst 4 or PVsyst5 >= .hor file?

Thank you in advance.

[André Mermoud]

I don't know the format of the PV*SOL horizon files, but in PVsyst you can simply create a CSV file of (Azimuth, Height) pairs values.

See the help for the exact format.

Now defining points every degree doesn't make sense. If so, PVsyst will "simplify" the horizon line by eliminating the unnecessary points, in order to get a max. of 120 points.

[george]

Dear Mr. Mermoud,

Thank you for the reply.

I already took a look at your horizon profile help page, and I am not sure I understand the explanation.

The PVsyst 4 used pairs of Azimuth, Height values, where Azimuths started from -120 and went to 120 = making it total of 240 Azimuths?

PVsyst 5 and PVsyst 6 use pairs of Azimuth, Height values, where Azimuths start from -180 and go to 180, but with incremental step of 3. So that means: -180, -177, -174 ... , 177, 180.

Did I understand that correctly?

[André Mermoud]

In any version of PVsyst, you can define pairs of (Azimuth, Height) as you like (not necessarily with identical azimuth steps).

Usually points spaced by 5-10° (or following the significant points of your horizon) are largely sufficient.

For diffuse calculations, you are advised to define the horizon all around the site (azimuth -180 .. 180°).

In the version 4, the number of points was limited. Some software gave horizon with 1 point every degree, which is completely useless. In these cases PVsyst reduced the number of points by performing some averages.

[george]

Thank you for the reply André.

 

In the version 4, the number of points was limited. Some software gave horizon with 1 point every degree, which is completely useless. In these cases PVsyst reduced the number of points by performing some averages.

 

Does this mean that in PVsyst version 4, the diffuse radiation calculation was also performed on the horizon with the following azimuth directions: -120 to 120?

Or in PVsyst version 4, the diffuse radiation calculations were performed with horizon consisted of -180 to 180 azimuth directions?

[george]

Dear André.

Can you please say more on how PVsyst 4,5 and 6 will deal with comment lines (lines which are not Azimuth, Height pairs)?

Here is an example of a .hor file:

 

STUTTGART DEU, N48.68, E9.22

Altitude: 248 m

# Timezone: UTC+01:00

-180 46

-177 46

-174 46

-171 46

-168 46

 

Will all versions of PVsyst (versions: 4,5,6) simply ignore the first three lines?

Thank you for the reply.

[André Mermoud]

The reading of custom Horizon files is really very restricted.

Only the first line may be a comment.

The next lines should be values Azimuth; Height;

We have indeed to modernize this reading for allowing a more flexible reading.