Hourly excel exchange input?

Paul:

I have reverted back to SAM 2014 because my power tower model needs to have a cavity receiver. I am modeling a sCO2 powerblock,and have an external (FORTRAN) program that provides the performance. Since it is a molten salt tower, I can reasonably assume for most time slots that the turbine runs at design. I have a script that sets the Thigh, Tlow of the power block and the salt storage based on external modeling of the performance of the engine. It is recuperated, so Tlow is the temperature of the working fluid in the hot heat exchanger, and I put an offset to the salt temperature in the HX.

The problem is that the sCO2 cycle is strongly influenced by the heat rejection temperature, which is tied to ambient. The SAM code adjusts efficiency (or appears to) based on the characteristics of a steam Rankine cycle. The 2014 code does not have a user defined power block option.

I thought to use the Excel Exchange. A possibility is to provide a table of turbine efficiencies based on the hourly ambient temperature. I would also need to adjust the design point temperatures to match so SAM does not try to adjust the provided efficiency.

The help file starts to address "Annual Schedules and Excel Exchange", but it cuts off mid-sentence. I cannot tell if I can put in an hourly efficiency, calculated in excel from an hourly ambient temperature. If so, how do I do that?

Since I am using SAMUL scripting, I would be happy to do the adjustment from there as well if it is possible.

Any info you can provide on how to input an hourly PB efficiency would help.

Thanks
Chuck

Hi Chuck,

I don't think that approach will work, because there is not an input variable for the hourly efficiency values that you can use Excel Exchange to assign a value to. I will check with the CSP team to see if they can suggest a workaround solution to your problem.

Best regards,
Paul.