Help Needed: Issue to add the DNI values 1MWe Parabolic Trough CSP Simulation

Hello everyone,I’m trying to simulate a 1 MWe gross output solar thermal power plant using the Parabolic Trough (Physical Model) in SAM. However, I’m consistently getting negative or zero output results, and I can’t figure out why.Here are my configuration details:

• Project Location: Gurgaon, Haryana, India
• Weather File: NSRDB data for 28.41°N, 77.42°E (Gurgaon)
• Design Gross Output: 1 MWe
• Field Aperture Area: 8175 m²
• HTF: Therminol VP-1
• DNI: 600 W/m²
• Inlet/Outlet Temp: 232°C / 390°C
• Cycle Thermal Efficiency: 0.333
• Gross-to-Net Conversion Factor: 0.9
• System Control Settings: mostly default
• Other Notes:
  • I’m seeing negative thermal energy to power block.
  • Startup/shutdown losses may be affecting results.
  • Could not determine if the issue is with field sizing, dispatch settings, or loop parameters.

I’ve attached the   and a research paper that I take the values file for reference:
File Name: Could someone please review it and guide me on:

1. Why the simulation is giving negative output.
2. What settings should be changed to get realistic results.
3. Any advice on loop configuration, thermal storage (if needed), or power cycle tuning.

Thanks a lot in advance!
Abhishek

Hi Abhishek,

Many of the inputs in your file are different from the default values, which makes it hard to identify the cause of the negative output.

For the CSP models, if you are modeling a system that varies significantly from the default design, we recommend starting with the default system and then systematically changing inputs one or two at a time and running a simulation before changing the next few inputs. This way, you can tell what input caused the unexpected result.

In your file, I was able to get positive generation although with a small capacity factor by making the following changes:

• On the Solar Field page, change from Option 2 to Option 1 and set the solar multiple to 2. This ensures that the solar field is large enough to provide heat to the thermal energy storage (TES) system in addition to delivering power to the grid.
  
• On the Collectors (SCAs) page and Receivers (HCEs) page, click Apply Values from Library so that the collector and receiver parameters are more realistic.

I also changed the curtailment array from ones to 1e+38 to avoid limiting the system output to 1 MW so I can see what the model is doing.

Best regards,
Paul.
 

I attached the SAM file and also got the positive and accurate values. Now I just want how can I put the values(DNI like that) in the SAM before the simulation. What I mean is in the image 2 this is the result of my file and in the image 2 is the research paper results(PC electrical power output: gross in MWe vs DNI). Now, I want to change the values according to my self of DNI so I can get the results like research paper. How can I put these values and also can I get the results for 1 minutes or 1 seconds?
Abhishek

Hi Abhishek,

SAM's CSP models read DNI and meteorological data from the weather file indicated on the Location and Resource page. The file must meet the format requirements described in the "SAM CSV Format for Solar" topic of Help:  samrepo.nrelcloud.org/help/weather_format_sam_csv_solar.html

For the data requirements for the Physical Trough model, see  samrepo.nrelcloud.org/help/weather_data_elements.html .

To replicate the results described in the research paper, you will need access to the weather data that the researchers used for their analysis.

Best regards,
Paul.