The solar radiation layers are simulations of solar radiation based on the Digital Surface Model. The simulation considers the topographic situation (surrounding, slope, exposition) as well as time-based variation of the sun radiation for a specific geographic location. The result is a raster visualization of the sun duration per pixel (with 1 m ground resolution). The simulation is configured to return the sun hours per pixel for a given day. Currently 3 days were calculated: 15/02 (winter), 15/05 (spring) and 15/08 (summer).
The solar radiation analysis is based on the solar radiation toolset of the ESRI ArcMap toolbox. A detailed documentation can be found in the corresponding documentation by ESRI: http://desktop.arcgis.com/en/arcmap/10.6/tools/spatial-analyst-toolbox/area-solar-radiation.htm
ESRI Documentation
The analysis used the following parameters:
- Input raster: Digital Surface model provided by the Administration de la navigation aérienne (ANA) based on a LiDAR flight from 2017. (DSM available here : https://data.public.lu/fr/datasets/digital-surface-model-high-dem-resolution/ )
- Latitude : 49.46 °
- Time configuration : Time Within a day (for 3 dates: 15/02 winter, 15/05 spring and 15/08 summer)
- Hour interval: 0.5 The solar radiation was calculated in 30 min. intervals and summed up per day.
- Slope and aspect input : The slope and aspect rasters are calculated from the input digital surface model
- Calculation directions: 32, which is adequate for a complex topography.
- Diffuse proportion : 0.3 for a generally clear sky conditions.
- Transmittitivity : 0.5 for a generally clear sky.
- Output raster: The result is an output raster representing the duration of direct incoming solar radiation.
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