Hello everyone today am looking at the types of solar radiation.
Types of Solar Radiation
The total solar radiation, often called as global radiation is the sum of direct, diffuse and reflected radiation. The solar radiation available to us is always a mix of the above mentioned three components. The approximate percentage of each of these components varies as the different parameters, such as weather, location etc. change. In order to monitor and analyze the performance of solar plants, monitoring the global radiation is essential but depending upon the plant capacity and location, monitoring the composition of global radiation might also make sense.
Direct radiation is received from sun rays propagating from sun to the earth. Direction radiation is also called as beam radiation or direct beam radiation. As direct radiation is sun rays propagating, shadows of the objects which come in the way of sun rays are formed. Shadows show the presence of direct radiation.
In sunny regions and during summers, direct radiation explains for almost 70-80% of the total radiation present. In solar plants, solar tracking is needed to absorb most of the direct radiation. If solar tracking system is not kept, valuable direct radiation would go un-captured.
Direct radiation has a fixed direction. Diffuse radiation does not have any fixed direction. When sun rays are scattered by particles present in the atmosphere, these scattered sun rays explain for the diffuse radiation. Shadows of the objects will not form if only diffuse and no direct radiation is present.
As pollution rises the amount of diffuse radiation also goes up. In hilly regions and during winters, the percentage of diffuse radiation rises up. Maximum amount of diffuse radiation is trapped by the solar panels when they are kept horizontally. This means, in case of solar panels which are at an angle to track the most of the direct radiation, the quantity of diffused radiation captured by the panels will go down. Larger the angle which solar panels make with the ground, lesser would be the ammount of diffuse radiation captured by the panels.
Reflected radiation is the component of radiation which is reflected from surfaces other than in the air particles. Radiation reflected from hills, trees, houses, water bodies explains for reflected radiation. Reflected radiation generally accounts for a small percent in the global radiation but can help as much as 15% in snowy regions.
Global radiation is the addition of direct, diffuse and reflected radiation