LED Wattage , angle of the installation and height is what will derive the area coverage of Solar Lights.
Installation height of the light depends on the LED Wattage. Higher the wattage the installation height and the installation distance is also higher.
If the light falls flat, the angle of installation also should be considered in order to get more area coverage. Below table gives a fair idea on the same:
|LED Wattage||Area Coverage|
|0.2 "5 Watt||1 "3 Meter|
|5 "8 Watt||4 " 6 Meter|
|8 " 20 Watt||8 "15 Meter|
|20 "50 Watt||20 " 25 Meter|