DNI for power tower

I noticed that in the system CSP parabolic trough collectors, SAM uses the DNI-cosine effect product values, but for the CSP solar tower system, it uses directly the DNI values. is that you can me explain it ??

Hello,

I think you are referring to the fact that the physical trough model reports a variable in the results named "Collector cosine effect - cos theta" that the power tower model does not report. The power tower model reports the "Total incident thermal energy" that is comparable to the physical trough model's "Thermal energy absorbed."

Both models calculate the solar radiation incident on the solar field, but they use different variables in the calculations, and report different variables in the results.

Best regards,
Paul.

thank you very much paul

I understand is that in the parabolic trough, SAM does not use the total energy incident.

but, in the solar tower, it uses the total energy incident.

other notes, the hourly evolution of the gross power produced following the DNI-cosine effect product in the parabolic trough, but in the solar-paneled tower, it follows the DNI.

Can you explain why?