Solar tracker is the broad and unspecified term used to illustrate devices that are being used to adjust various payloads towards the sun. There are many kinds of solar trackers i.e. photo voltaic panels, Reflectors, lenses and other optical devices. Angle of incidence will be decreased between incoming light and a photo voltaic panel by standardized photo voltaic trackers. Installed power generation plants then increase the level of energy production. 85 per cent of commercial sector use standard photo voltaic techniques to enhance the production and it will expand much more in coming 2012.
Commonly two types of thermal applications are being used in Solar trackers i.e. concentrated photo voltaic (CPV) applications and concentrated solar thermal (CSP) applications. These applications are widely used to enable the optical components in both of the procedures. The optics is not direct component of sunlight and big source to gather energy from sun radiations.
Photo voltaic solar trackers are being classified into two types i.e. Standard Photo Voltaic Trackers and Concentrated Photo Voltaic Trackers. Each category has its own axes, architecture, vertical supports, intended applications, foundations and driven types. Photo voltaic panels diffuse sun radiations directly from the sky. They gather all available light of sun. Concentrated Photo Voltaic is the direct element of incoming sunlight and maximum level of energy being collected. This tracker is used in low concentration application also. Incoming light only focus to a photo voltaic collector to adjust the optics.
Many factors affect the selection of Solar trackers i.e. magnitude, electric rates, incentives, latitude, weather and constraints. Tracker axes make groups for photo voltaic trackers by depending on the number and orientation of axes. Single axis tracker increases by 30 per cent and dual axis tracker increases more 6 per cent in efficiency. There are many types of trackers used to capture sunlight to convert it in solar energy, some are as follows:
* Horizontal Single Axis Tracker (HSAT)
* Vertical Single Axis Tracker (VSAT)
* Single Axis Trackers
* Tilted Single Axis Tracker (TSAT)
* Polar Aligned Single Axis Trackers (PASAT)
* Dual Axis Trackers
* Tip – Tilt Dual Axis Tracker (TTDAT)
* Azimuth-Altitude Dual Axis Tracker (AADAT)
In single axis trackers rotation of single axis is used which now with advanced tracking algorithms can be align in any fundamental direction. In horizontal trackers face of the module remains parallel to the axis of rotation. The axis of rotation remains horizontal to the ground. It also helps to cut down the cost. Similarly, other trackers are being used to concentrate solar reflectors or lens leaning towards the sun to capture sunlight in photo voltaic panels. The concentrated light must be directed to the device which is near to the focal point of the lens.