PVWatts (use true or magnetic AZIM)

[VGdublin]

So, I got a layout from one of the installers. It has true and magnetic azim. Which one do I use in PVWatts? thanks!

[VGdublin]

The same question for SAM too. I assume they both use the same data. I have been using true Azimuth.

[sensij]

If you read the PVWatts online help, you'll find the following:

Azimuth (deg)

For a fixed array, the azimuth angle is the angle clockwise from true north describing the direction that the array faces. An azimuth angle of 180° is for a south-facing array, and an azimuth angle of zero degrees is for a north-facing array.

[VGdublin]

Duh!

Thanks for your help! I am sure I ready the help but didn't read the all important word.

[J.P.M.]

So, I got a layout from one of the installers. It has true and magnetic azim. Which one do I use in PVWatts? thanks!

You use TRUE NORTH.