Design And Construction Of An Arduino Based Dual Axis Solar Tracking System

1.0 BACKGROUND OF THE STUDY
Energy is required for the different applications in our daily life. There are so many resources of power generation. 85% of power is produced from fossil fuels (Anuraj & Gandhi, 2014). Due to the depletion of the fossil fuel, renewable energy resources are required. Wind energy, geothermal energy, tidal energy and solar energy resources are some of the most efficient renewable energy resources. Solar energy can be converted in to two forms of energy, i.e. thermal energy and electrical energy. These can be achieved by using some instruments. Solar energy can be converted into electrical energy by using PV (photovoltaic) cells. Rays from the Sun light falls on the PV panel, which generates DC power. This DC power has a direct correlation with the intensity of the light incident on panel. And the intensity depends on the angle of incidence between incoming light and a flat photovoltaic (PV) panel according to Anuraj et al. (2014).
A tracking system can keep the angle of incidence equal to 0. Sun tracking systems can increase the power output of solar power plants by 25% to 40%, depending on the geographic location. A single axis tracker can increase power output by 26%, while a dual axis tracker increases power by 32% (Deb & Roy, 2012). Single axis trackers follow the Sun from east to west, while dual axis trackers track the Sun by altitude (up/down), since the Sun moves across the sky throughout the day. Mousazadeh et al. (2009) calculated that the amount of power gained by tracking can come close to an ideal 57% (Mousazadeh et al., 2009).
Tracking systems compose of mechanical mechanism and electronic sensors. Mechanical mechanism rotates the flat panel and this rotation is controlled by electronic sensors.
The controlling process can be classified into two processes, namely passive control unit (Arsalan, 2013) and electro-optical control unit. The passive control unit is a system conducted without any electronic device. The electro optical control unit uses solar detecting devices which are sensitive to solar radiance photo sensors (LDR). Third controlling process is used in this work.

1.2 STATEMENT OF THE PROBLEM
One of the major problems facing solar energy systems is the efficiency as the sun moves on the celestial sphere, and this makes it difficult to achieve higher power output from the solar panel. In other to solve this problem, a solar tracker was built. Solar tracker is a device that tracks the position of the sun and set the solar energy conversion system focusing normal to the sun beams. A single axis tracker was first built which was only able to increase power output by 26% due to the fact that it Single axis trackers follow the Sun from east to west (Deb & Roy, 2012). This paper presents a design focused on harnessing the maximum available solar radiation using dual-axis tracking mechanism. The tracking mechanism is designed to focus the solar conversion system perpendicular to the rays of the sun (sun beams) at all time of the day relative to the position of the sun in the sky dome.

1.3 AIM AND OBJECTIVES OF THE STUDY
The aim of this study is to build an intelligent dual-axis solar tracking device for solar system usage. The objectives of the work are:
i. To fabricate a solar tracking device with dual actuator, which one of the actuators tracks the east to west motion of the sun while the second linear actuator tracks the seasonal motion/daily altitude of the sun
ii. To harness maximum solar energy
iii. To provide a stable electric power supply using solar energy.

1.4 SCOPE OF THE STUDY
The scope of this work covers building a dual axis solar tracking system using two linear actuator .The driving mechanism for the motion are two direct current linear actuators of 12V each, which one of the actuators tracks the east to west motion of the sun while the second linear actuator tracks the seasonal motion/daily altitude of the sun. The main task of the tracking mechanism is to focus solar energy conversion system perpendicular to the sun to maximize the absorbed solar radiation and minimize the energy consumption for tracking system. The movement of the sun on the celestial sphere was the bases of the tracking mechanisms angles design.

1.5 SIGNIFICANCE OF THE STUDY
To the country, this study will serve as means of ensuring a steady power supply which will help the country (Nigeria) to be able to grow its economy, and attain its Millennium Development Goals (MDGs).
To the student, this study will help the student involved becoming familiar with solar energy generation and also help him to understand how he can increase the power of solar energy by electromechanical means.