Stow angle prevents energy collection

If I create a CSP empirical parabolic trough model with commercial financing (what happened to the no-financing option??) and then change the Stow Angle in Solar Field from 170 degrees to 179.99 degrees, I get more energy production (as expected). But, when I change it from 179.99 to 180, energy production goes to zero. Why is this?

Hello,

It looks like 180 degrees is the upper limit for the stow angle (it represents a vertical collector angle). If you want to model a 180 degree stow angle, you should use the 179.9 value.

Best regards,
Paul.