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dtarin

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Everything posted by dtarin

  1. Thank you for the link, haven't needed to use this in a few years.
  2. There are a number of ways to import your own data if you just want to look at terrain arbitrarily. Here is one. https://portal.opentopography.org/datasets
  3. Add "dummy" mppt inputs by modifying the OND file of the inverter. You can add for example two (2) mppt inputs if it is a 50-50 split, add one subarray with (1) mppt and the second subarray with (1) mppt, which will be equivalent to one inverter. Go into power sharing and allocate it evenly. If it is a non equal split, for example module A is 70% and module B is 30%, then add ten (10) mppt inputs to the OND file, and allocate seven (7) to subarray A and three (3) to subarray B. There looks like a bug though, I am not seeing the information being generated in latest version. Should there be something displayed @Michele Oliosi? I have an unequal number of strings for each subarray and different ratios, but when I click enable power sharing, nothing really happens.
  4. Mismatch loss is not calculated, it is entered by the user under detailed losses menu. Mismatch due to differences in IV characteristics is relatively low, but it is one contribution to mismatch losses; temperature and irradiance differences also contribute to mismatch losses.
  5. These are not equivalent models, so the comparison with GHI is not a valid comparison. The locations are very different, as Michele noted, the site by the equator has an optimal tilt around 6-7 degrees which means you are limited in your POA transposition gain. The Santa Catarina site is further from the equator and realizes a higher transposition gain from the 27 degree tilt, which makes up for the lower GHI by comparison. It also has a lower temperature loss compared to Ceara.
  6. Is there any documentation available detailing the capabilities and restrictions for the PVsyst trial?
  7. They are in different locations, and you have different tilts. Without knowing these and overall orientation details, no.
  8. These are not equivalent models. The global incident in collector plane shows a 7% gain for sim#1, whereas it is a loss in sim#2. Something is off with the orientation or shade scene. Additionally, there is a large difference in ambient temperature, and sim#1 has a lower temperature loss compared to sim#2. The latter you can do nothing about.
  9. It does not update DC/AC ratio. In order to check, look at the 8760 at the inverter output. Ensure that PF is being applied such that it matches the PNOM definition in the OND file.
  10. If it is a P90 weather file, then you are correct, do not include interannual variability or any additional uncertainty for the weather resource. You will just need to include the additional sources of uncertainty in the simulation (soiling, mismatch, etc). The P90 weather file already includes in its construction the interannual variability and the solar radiation model uncertainty.
  11. If your shade scene has independent trackers (importing from .PVC or using zone creation), you always need to select the pair. Since you have specified the same pair for each variant, now your elec. effect losses are equal. However, be sure to select a representative pair of trackers. Calculate the weighted average tilt for all trackers, then select a pair at that tilt. The phi limits might be a display bug. I have a model with no terrain and it is showing the same phi limits (+/- 79.9) on the backtracking strategy for a +/-60 phi range. However, if you check your 8760, you will see the trackers do not exceed the input phi min/max, in your case, +/- 55.
  12. In the shading scene, which trackers are selected under backtracking management? Have you selected the same trackers in both instances? This can have an impact shading calculations.
  13. You can only have one module in one sub-array, but you can have multiple sub-arrays and multiple modules into a single inverter. The inverter will need mppt inputs defined, and then allocated per each sub-array. See previous threads:
  14. It depends on the weather file you are using. What is your weather resource? If it is a standard TMY file, it is a P50 estimate. Whether it is gross or net depends on if you have included all loss factors for your system, i.e. AC losses, transformer losses, night and auxiliary loss, degradation, etc.
  15. Individual PV modules global degradation factor is auto-calculated based on the Avg degradation factor defined under Model and on the year of simulation. For the first year of operation, it is half the degradation rate. So there, you have defined 0.45% as the standard degradation rate. In year 1, the Individual PV Modules Global Degrad. Factor is 0.45%/2. For year 2, it will be 0.45% + 0.45%/2, and every year thereafter will add the full degradation rate. The Avg degradation factor comes from the module datasheet. To run full 30 years, enter your settings here and save and exit. Then go to advanced simul. and click Aging Tool. Follow the instructions there, it is self explanatory. You can choose the weather file, select if you want to generate 8760 files, pdf reports, or individual variants for each year. Specify every # of years (1 to run each year) and total years. On mismatch, this is not well accounted for. There are some studies but most installed PV is 5-6 years old and technology has changed every few years.
  16. Typical cell width range is 15.6cm to 21cm.
  17. Twin half-cell does not double the number of strings, it halves the modules. You still have only one module supplying power. You should use electrical effect. 30 albedo is high. Is the roof white?
  18. I dont have the OND file, but my guess would be that 1) the huawei has a wider mppt voltage range and 2) it has a higher input current rating compared to the sungrow
  19. Calculate your voltage drops for each leg and the combined conductor to the point of interconnect. Set your loss fraction @ stc appropriately based on this.
  20. It is due to your model. What is your albedo and other bifacial settings like height from ground? Where is the project located, what is the GHI? You have a 78% GCR, which is extremely high, and your tilt is only 10 degrees. You will not see a high bifacial gain with that design.
  21. This is not done inside PVsyst. Calculate your Pxx factors and multiply your P50 data by them. Example: P90 = 0.91*P50 P99 = 0.83*P50
  22. For a graph: Run simulation Go to detailed results Click hourly graphs Under time axis definition select monthly Under variables to be drawn, select energy injected to the grid (or whatever you want to see) Select bar chart or graph Specify units for energy (kWh, etc) Click graph To export to excel, click export values to clipboard For a table: Run simulation Go to detailed results Select table Select Energy use and Users Needs On the right select Energy injected to the grid Define units of energy Press Table This can also be exported to excel
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