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Pertaining to capacity or PR testing, the following equation is frequently referenced for total irradiance calculations: E_Total = E_POA + E_Rear * 𝜑 ...where 𝜑 is equal to the module bifaciality factor. My question concerns the E_Rear term: if a PV system has a pyranometer installed in the rear plane of array in such a way that it is unobstructed by structures such as the torque tube, and the E_Rear used for the physical PV system is the measured RPOA from this pyranometer, what do you recommend using for the E_Rear term to calculate an equivalent model-side E_Total? Would the E_Rear term be the output variable GlobBak, a combination of factors such as GlobBak + BackShd, or something else? Reference: Waters, Martin, Chris Deline, Johan Kemnitz, and Jeffrey Webber. 2019. Suggested Modifications for Bifacial Capacity Testing: Preprint. Golden, CO: National Renewable Energy Laboratory. NREL/ CP-5K00-73982. https://www.nrel.gov/docs/fy20osti/73982.pdf

Hello, I’ve run two PVsyst simulations for the same rooftop PV system on a warehouse in Malaysia. Both simulations have identical parameters: System size: 3423 kWp (6339 × JinkoSolar JKM-540M-72HL4-TV) Inverters: 12 × Sungrow SG250-HX (total 3000 kWac, Pnom ratio: 1.141) BESS: 2 × Huawei Luna2000 (2936.4 kWh usable capacity) Orientation: 6 fixed tilts (e.g., 13°/-20°, 13°/160°, etc.) User load: Fixed profile, ~4800 kWh/day (1,752,000 kWh/year) Self-consumption strategy with battery charging from PV surplus and discharging to support load The only difference between the two runs is: Case 1: Grid injection allowed (Grid reinjection: Yes) Case 2: Grid injection not allowed (Grid reinjection: No) However, the annual "Produced Energy" output differs dramatically: Case 1 (Inject): ~4.97 GWh/year, PR = 82.27% Case 2 (No Inject): ~1.74 GWh/year, PR = 28.81% Other metrics like EArray, E_InvOut, and load-supplied energy (E_Solar = 1.74 GWh, SF = 99.26%) are identical in both cases. My questions: Why is the “Produced Energy” (and PR) so much lower in the no injection scenario when the PV array performance and load supply remain the same? Is PVsyst not counting excess PV generation as “Produced Energy” when it is curtailed (i.e., when the battery is full and there's no injection allowed)? Is there a better way to represent "total generation potential" in a self-consumption system without grid injection, so that I can compare energy yield more realistically? I want to ensure I'm interpreting these results correctly, especially for techno-economic reporting under self-consumption-only policies (e.g., Malaysia’s SELCO guideline). Thank you!