Comparative Performance Evaluation of MS and DSG Solar Tower CSP Plants

Dear Paul,
I intend to make an impartial comparative study of MS and DSG Solar Tower CSP Plants for a particular site with thermal storage. For MS plant, i was able to enter the desired thermal storage inputs in SAM but could not do the same for DSG plant. At first, I thought DSG plants are without thermal storage but when i read from literature that they does not include explicit thermal storage i became confused. Could you kindly give me a guide. Is it also possible to simulate the MS and DSG solar tower CSP plants without storage? If yes how do i go about it?
Your quick response is highly anticipated.
My best regards.
Mohammed Muye.

Dear Mohammed,
SAM's direct steam power tower model does not model storage. For a discussion of storage in power towers that includes a description of the challenges of using molten salt storage in a direct steam system, see this CSP Today article ( PDF 181 KB ) by Arnold Leitner, former CEO of SkyFuel, Inc.
To model a molten salt power tower without storage, on the Thermal Storage page, set Full Load Hours of TES to zero. You should generate a new heliostat layout and reoptimize the solar field each time you change the storage capacity or other parameters.
Best regards,

Paul.

Dear Paul,
Thanks for your contribution. With Full Loads Hours of TES set to zero, which indicate molten salt solar tower with no storage will it be correct if i set the solar multiple to 1. I am thinking so since from literature, it was reported that CSP plants without storage should have solar multiple less or equal to one.
My kind regards,
Mohammed Muye

Dear Mohammed,
The optimal solar multiple for a power tower system without storage is likely to be smaller than for a system with storage. The exact value of the solar multiple will depend on the solar resource at the project location and the relative cost of the field and storage components. For a discussion of solar multiple for power towers, see the Modeling Power Towers in SAM webinar , just after minute 33:00.
Best regards,

Paul.

Dear Paul,
I quite agree with you that the optimal solar multiple for power tower system is smaller than that with storage.
I ran a simulation for MS CSP Technology without storage for solar multiple 1 and 2. The results i got shows that the annual energy generation for solar multiple 1 is about 21% higher than for solar multiple 2.I shall go over the Modelling Power Towers webinar again as you directed. Thanks for your response and my kind regards.
Mohammed Muye

Dear Mohammed,
Each time you change the storage capacity or solar multiple, be sure to generate a new heliostat layout and optimize the field geometry on the Heliostat Field page. You can check the Always layout automatically and Optimize solar field geometry boxes to have that done automatically each time you run a simulation. Othewise your system's solar field is optimized to deliver the wrong amount of heat to the receiver.
Best regards,

Paul.