- Posts: 4
How input thermal mass?
- matlaw
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06 Dec 2013 21:19 #2027
by matlaw
How input thermal mass? was created by matlaw
For a generic solar system (within concentrating solar power - when using an imported efficiency table), is it possible to set the thermal mass - the amount of power that is used just to get the system up to steam generation in the morning?
I can't seem to find an entry for that anywhere amongst the losses.
I also can't seem to see how to do a search of just the support section of this website to avoid asking questions that have been asked already!
Thanks,
Matthew
I can't seem to find an entry for that anywhere amongst the losses.
I also can't seem to see how to do a search of just the support section of this website to avoid asking questions that have been asked already!
Thanks,
Matthew
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- pgilman
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- Posts: 5423
13 Dec 2013 16:57 #2028
by pgilman
Replied by pgilman on topic How input thermal mass?
Hi Matthew,
Sorry for the slow response. My colleague in the NREL CSP program tried to respond but had trouble getting the website to work. Here's what he wrote:
BEGIN
The generic solar system model is essentially a steady-state model in that it solves the energy balance from time-step to time-step without considering the temperature and enthalpy of the system in a previous state. The one exception is in the power cycle model, where we do have a startup energy requirement. In this case, the startup energy is just a running tally so that the power block is not allowed to generate power until the startup quota has been met. Because this is a simple energy balance approach, you can safely extend the power block startup requirement to account for field startup.
the solar field without operating the power block. For example, when the field operates and charges thermal storage that will be used later by the power block. In the hourly results, you will see that the field is providing energy to thermal storage when in fact it would be just starting up, but this mismatch is eventually accounted for when the power block starts up. On balance, the total power production is correct, but the more detailed results will be misleading.
END
As for searching the forum, you are correct to note that the search box searches all content on the website. It is possible to refine the search results to show only content in the support forum. When you see the results of a search (from the search box at the top right of the page), click the Content tab, and then check Support Question under "Only of the type(s)." I will work with the website administrator to see if we can simplify this process.
Best regards,
Paul.
Sorry for the slow response. My colleague in the NREL CSP program tried to respond but had trouble getting the website to work. Here's what he wrote:
BEGIN
The generic solar system model is essentially a steady-state model in that it solves the energy balance from time-step to time-step without considering the temperature and enthalpy of the system in a previous state. The one exception is in the power cycle model, where we do have a startup energy requirement. In this case, the startup energy is just a running tally so that the power block is not allowed to generate power until the startup quota has been met. Because this is a simple energy balance approach, you can safely extend the power block startup requirement to account for field startup.
the solar field without operating the power block. For example, when the field operates and charges thermal storage that will be used later by the power block. In the hourly results, you will see that the field is providing energy to thermal storage when in fact it would be just starting up, but this mismatch is eventually accounted for when the power block starts up. On balance, the total power production is correct, but the more detailed results will be misleading.
END
As for searching the forum, you are correct to note that the search box searches all content on the website. It is possible to refine the search results to show only content in the support forum. When you see the results of a search (from the search box at the top right of the page), click the Content tab, and then check Support Question under "Only of the type(s)." I will work with the website administrator to see if we can simplify this process.
Best regards,
Paul.
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