The solar radiation and PV output will change if there are local hills or mountains that block the light of the sun during some periods of the day. PVGIS can calculate the effect of this using data about ground elevation with a resolution of 3 arc-seconds (around 90m). This calculation does not take into account shadows from very nearby things such as houses or trees. In this case you can upload your own horizon information.
- PVGIS interface - Calculated horizon box
- Non-interactive service - printhorizon
Outputs
This tool outputs a list of horizon height values for the given location. In addition, it will output a list of sun elevation angles at the June and December solstice. The horizon height is given at 48 equidistant directions starting from north and moving clockwise towards east, south and then west. The sun elevation angles are given at half-hour intervals starting at 00:00UTC.
csv
The header consists of a few values:
- Latitude [decimal degrees]
- Longitude [decimal degrees]
This is followed by 48 lines with the following information:
- A_hor [°] - Azimuth angle of the horizon information (0° = S, 90° = W, -90° = E)
- H_hor [°] - Horizon height from the horizontal plane in the given direction.
- A_sun(w) [°] - Azimuth angle of sun at the winter (December 21) solstice.
- H_sun(w) [°] - Sun elevation from the horizontal plane at the winter (December 21) solstice.
- A_sun(s) [°] - Azimuth angle of sun at the summer (June 21) solstice.
- H_sun(s) [°] - Sun elevation from the horizontal plane at the summer (June 21) solstice.
json
{ "inputs": { "location": {
"latitude": 45.809,
"longitude": 8.632,
"elevation": 223 }
"horizon_db": "DEM-calculated"
},
"outputs": {
"horizon_profile": {
{
"A": -180,
"H_hor": 0 },
{...}
},
"winter_solstice": {
{
"A_sun(w)": -180,
"H_sun(w)": 0 },
{...}
},
"summer_solstice": {
{
"A_sun(s)": -180,
"H_sun(s)": 0 },
{...}
}
},
"meta": { "inputs": {
"location": {
"description": "Selected location"
"variables": {
"latitude": {
"description": "Latitude",
"units": "decimal degrees"
},
{...}
}
},
{...}
},
"outputs": {
"horizon_profile": {
"description": "Horizon profile"
"variables": {
"A": {
"description": "Azimuth (0 = S, 90 = W, -90 = E)",
"units": "degrees"
},
{...}
}
},
{...}
}
}
}