Molten Salt Tower Error Par_store_pump?

Hello,

I am not sure if I have found an error in the computation of the electric consumption of the Storage pump in the Molten Salt Tower Power Plant model. (In my view the storage pump is the pump located after the hot salt storage and before the power block?).

It seems that for the calculation even if I set the parameter "Required pumping power for HTF through storage" to zero the parasitic consumption is calculated as with the parameter "Required pumping power for HTF through power block" x ("Massflow to power block" + "Massflow from storage").
I think that the value "Massflow from storage" should be neglected in this case.

Maybe you could check this or tell me why this is right in this case, please?

Thanks,

Christoph

Dear Christoph,
It turns out that the molten salt power tower model does not use the "Required pumping power for HTF through storage" input on the Parasitics page. That input is used by the trough models when the solar field HTF is different from the storage fluid. Because the tower model uses the same fluid (salt) in the field and storage system, the model does not calculate a storage pumping loss. We should have disabled that input for the tower model.
SAM uses the same basic set of equations to calculate the parasitic losses for all of the CSP models. Those equations are described in Chapter 5 of Wagner, M. J.; Gilman, P. (2011). "Technical Manual for the SAM Physical Trough Model." 124 pp.; NREL Report No. TP-5500-51825. ( PDF 3.7 MB ).
Best regards,

Paul.