Multiconcept Methods to Enhance Photovoltaic System Efficiency

Table 2

Sun tracker types and gain.

Type	Description	Gain in power	Ref.
Single axis	(1) The rotation is on E-W direction, and on N-S, the panel is tilted at 30°. It is an active tracker, based on closed-loop (two photodiodes are used).	15.3%—cloudy day; 16.2%—partially clear day; 23.2%—clear day	[27]
	(2) The rotation is on N-S direction. It is an active tracker, based on closed-loop (algorithm). The system movement is electromechanical.	20%	[28]
	(3) The rotation is on E-W direction, and it is an active tracker with algorithms. The fixed system is near earth for site A, is one of the 90 sun trackers but deactivated for site B, and is tilted at 30° for site C.	37.7% site A; 30.4% site B; 31.5% site C	[29]
	(4) The rotation is on E-W direction, and it is an active tracker based on closed-loop (sensors).	45%	[30]
	(5) The rotation is on N-S direction, and it is a passive tracker based on two bimetallic strips.	23%	[31]
	(6) Tracker with three positions (fixed angles) for morning, noon, and afternoon.	24.5%	[32]
Dual axis	(1) It is an active tracker with a tracking algorithm. The system movement is electromechanical.	42.6%	[33]
	(2) Equatorial sun tracker. It is an active tracker with sensors.	108 Whr/m^2—cloudy day; 603 Whr/m^2—clear day	[34]
	(3) It is an active tracker based on MPPT.	37.1%	[35]
	(4) It is an active tracker based on an algorithm.	24.59%	[36]