To make solar energy more viable, the efficiency of solar array systems must be maximized. A feasible approach to maximizing the efficiency of photovoltaic systems is through solar tracking. Photovoltaic panels (PV) are devices that cleanly convert sunlight into electricity and offer a practical solution to the problem of power generation in remote areas. The solar tracker designed and developed by AMEC offers a reliable and affordable method of aligning solar PV panels with the sun for the useful part of the day in order to maximize its energy output. AMEC’s Autonomous Solar Tracking System is a hybrid hardware/software system which automatically provides best alignment of solar panel with the sun, to get maximum power output. This is achieved by implementing astronomical calculations in the embedded software algorithm to compute the sun’s position in real-time and updating position of the PV panels along both altitude and azimuth axes. This method is called Dual Axis Solar Tracking and it greatly improves the energy output from your PV installation compared with fixed PV installations.
The PV panels convert the sun’s energy directly into electricity. They work most efficiently when thesun’s radiation is perpendicular to the panels. In the figure below, the panel on the left is mounted at a fixed angle and the suns rays fall at an angle thereby the intensity of light is spread out over a larger area thus producing less power.
In the next image, the PV panel is mounted on AMEC Dual Axis Solar Tracker, which keeps the panels facing the sun for the most part of the day. The sunlight strikes the panels with greater intensity thereby generating maximum energy of the PV system continuously throughout the day.
Research has shown that by using dual axis solar tracking systems, the efficiency of energy conversion improves by up to 40% compared with static PV installations.
Due to the rotation of the earth about its axis once every 24 hours, the sun seems to sweep a path in the sky giving the familiar sunrise and sunsets. The sun path is as given in figure below:
During winter season, the sun path is AA’ – as can be seen the sun rises South of East and stays low in the sky and sets South of West. Since the sun path is shorter, the solar days are shorter during the winter seasons. On the other hand, during summers, the sun path is CC’ – as can be seen the sun rises North of East and rises higher in the sky, almost reaching directly overhead and traces a longer path in the sky before setting North of West. Thus, days are longer in summers.
As the sun moves from East to West, its position is defined by two coordinates – Azimuth and Altitude as in figure below.
AMEC tracking system uses embedded microprocessor based control system which calculates the sun’s position in real-time using astronomical calculations and automatically adjusts the PV array to correct for the sun’s position. To keep the PV panels facing the sun, our tracking system moves the PV array along both altitude and azimuth axes – this keeps the array facing the sun at 90degrees.
AMEC solar tracker uses high quality hot dipped galvanized metal parts for the mounting structure. This makes it ideal for the hot and humid weather conditions of gulf countries.
The drive system comprises of high quality German brand motorized linear actuators driven by the power generated from the sun. The actuators are designed for solar tracking applications and have very nominal power consumption.
The controller for the dual axis tracker is housed in a robust NEMA 4x enclosure which protects the electronics against dirt, rain, sleet, wind-driven dust, splashing and hose-directed water. The controller has built in battery to maintain the system time even when disconnected from external power supply during maintenance/installation.
The dual axis controller for the tracking system needs to be initialized with correct location and time in order to function correctly. All user parameters can be entered into the controller manually via easily accessible push buttons. Alternatively, the controller can be connected to a laptop via serial RS232 port or USB port and configured automatically through our monitoring & configuration software on the computer. The PC software also shows the current status of the tracking system and solar position.