Results in tower CSP

Dear Paul,

I have a big question on my mind and I ask you to help me, please. I am simulating in SAM a CSP tower plant with 111 (MWe) of gross design turbine output, a solar multiple of 2.8 and 17.5 hours of storage.

I have adjusted the Dispatch Control as I show you in the attached image. Particularly in January, at 1:00 p.m. the turbine should only operate at a low percentage and then gradually go up.

When I simulate the plant, they give me the results that I show you in the other attached image. As you can see, in January, the generation goes down until 1:00 p.m. (so far so good), but after 3:00 p.m. the generation rises suddenly. The latter is rare, because according to Dispatch Control, it has period 2, which is equivalent to weighting the turbine with only 0.359 only. Why is the generation so high from that time on? Shouldn't it be a more gradual increase? What could be a possible explanation for this phenomenon? From 2:00 p.m. to 3:00 p.m. there is a very abrupt change.

Maybe there is something I am not considering.

I hope I was clear.

Thank you in advance for your kind response, please.

Francisco

Hi Francisco,

Please try attaching your images instead of inserting them into the message.

Best regards,
Paul.

Dear Paul,
Thank you. I attach the images and the SAM file of the simulation and solar data used. As you can see, it is striking that the change is so abrupt and does not follow the smoother production that I defined in Dispatch Control.
Thank you very much in advance,
Francisco

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Hi Francisco,

This seems like an unusual way to dispatch a CSP system. Can you tell me more about what kind of system you are trying to model?

Best regards,
Paul.

My idea is that the CSP plant delivers less energy when there is more solar radiation, that is why the configuration that I present. Because during the hours of more radiation, the energy will be delivered by another plant (PV).
But beyond the Dispatch Control that I present, the CSP plant has a behavior that is not normal, or am I wrong? The increase in the second part of the day should be smoother and not as abrupt as in this case.
What is your opinion? Is it a software problem? or will it be my mistake?