Bifacial snow model correction#1214
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implementations; update tests to check for bifi snow interaction
brtietz
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Code looks good for irradiance and power production calculations. I wonder about the "DC power loss due to snow" output. In the released version, this was a useful indiciator of what % of the panel was covered:
now it's a bit noisier with the bifacial calculations:
Is it worth adding an additional output (maybe just to detailed PV) that matches the old output such that it's easier to see what the snow model is doing?
I think in pvsamv1 Subarray X Snow cover (0-1) is sufficient for that visual checking. Agreed on PVWatts, I can look at adding a similar output. |
brtietz
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Thanks for adding the output and cleaning up the unused variables!
janinefreeman
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Looks good! Thanks!
| { SSC_OUTPUT, SSC_ARRAY, "tpoa", "Transmitted plane of array irradiance", "W/m2", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "tcell", "Module temperature", "C", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "dcsnowderate", "DC power loss due to snow", "%", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "snow_cover", "Snow coverage", "0..1", "", "Time Series", "*", "", "" }, |
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This description might be clearer as "Fraction of row covered by snow"
| { SSC_OUTPUT, SSC_ARRAY, "tpoa", "Transmitted plane of array irradiance", "W/m2", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "tcell", "Module temperature", "C", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "dcsnowderate", "DC power loss due to snow", "%", "", "Time Series", "*", "", "" }, | ||
| { SSC_OUTPUT, SSC_ARRAY, "snow_cover", "Snow coverage", "0..1", "", "Time Series", "*", "", "" }, |
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Same comment as pvwattsv7
-Fixes (NatLabRockies/SAM#1739)
-Add rear POA to heat transfer balance equation for determining snow sliding
-scale snow cover losses by poa_front / total poa, as snow is not shading rear of module
-Add test coverage for snow/bifacial interactions
-Confirm that snow model calculates no snow coverage for vertical arrays.