Using Parabolic trough Field collector DNI for Tower (Salt)

Hello just reading through the help and previously asked questions on this forum and all answers in regards to the design point DNI lead to using the parabolic trough "field collector DNI - Cosine product". If I wanted to get this value for a tower system would I put the parameters into the trough system and then use that value or use the "Resource beam normal irradiance given in the tower time series tab? Thanks in advance for the help.

In SAM 2017.1.17, for the molten salt power tower model, the "Design point DNI" input is on the System Design page. You can find a description of the input on the Help topic for that page.

The CSP Parabolic Trough, Solar Multiple topic in Help has a section devoted to choosing a reference DNI value, which describes two methods: Use the maximum incident DNI value, or find the reference DNI input value that minimizes dumped load. You could use those techniques in the trough model with your weather file to find the values to use for the power tower model as you describe.

You could also find the value in the tower model that minimizes field defocusing ("Field optical focus fraction" in the results), which is analogous to minimizing dumped energy in the trough model.

You might find the Statistics tab on the data viewer on the Results page (also available for viewing weather file data by clicking View Data on the Location and Resource page) to find the maximum values of time series data.

Best regards,
Paul.