Solar energy is ready to power our current generation and essentially lead us into the next with a brighter prospect for future in sight. And globally the awareness is rising to adopt the technology, aiding the growth and leaving fossil fuels behind. Although solar modules are at the centre of this technology, orientation and positioning of the module in the field or on the rooftop plays a major role in maximizing energy yield from the installation.
Why Positioning and Orientation are Important?
The more surface area of the module is exposed to the sun rays, the more energy can be harvested. However, Solar module is generally fixed on a position (unless solar tracker machinery is installed, which adds to the expense of the project) while sun moves around in the sky, making maximizing energy yield a problem. Correct orientation and positioning assures that solar modules get access to the sun throughout the day.
For example, Sun stays comparatively lower in the sky in the winters than Summer months. Therefore, in these months orientation of solar panels has to be more vertical, as solar rays will have to pass through more atmosphere to reach the panels. However, in summer months, the sun stays much higher in the sky, therefore, it has to travel less distance to reach earth’s surface. So, horizontal orientation of solar modules can easily work efficiently in harvesting solar energy in these seasons.
Therefore, it is apparent that idea of orientation greatly impacts on accessibility to the sun rays.
Solar modules have to face the Sun at all times of the year in order to maximize energy yield. Solar plant engineers achieve this by facing the modules towards the South in the northern hemisphere and towards the north in the Southern hemisphere. This is generally referred to as the ‘tilt’ of the solar system.
India has 29 states and 6 union territories within the 8°4′ to 37°6′ North latitude and 68°7′ to 97°25′ East longitude boundaries. The topography of India includes Deccan plateau, the Himalayan Mountain range, rivers, deserts, and tropical landscapes. As a rule of thumb, the tilt in north-south direction is taken to be equal to the latitude of the place where the plant is situated. Thus, solar modules are in more tilted position in Punjab than in Tamil Nadu. This has an effect on the Ground Coverage Ratio (GCR) as tilted modules occupy less space.
The Sun follows a different path through the sky during winter than in summer as we move away from the equator. So, in order to capture as much energy as possible from the Sun throughout the year, solar modules need to be tilted by an angle of ±5° or ±10° (depending on latitude) 3 or 4 times a year. This is called seasonal tracking. For small residential systems, seasonal tracking is often done manually but for large arrays in utility scale plants, this is achieved by mechanical device (gears, actuators etc.).
The best way to capture maximum amount of the solar energy is to track the Sun’s path through the sky throughout the day and also from one season to another. This is called dual axis tracking. As solar plants are getting larger, this technology is gaining prominence.
So, as it turns out, there is a lot to think about regarding solar modules if you are to maximize the energy yield. However, capable EPC solutions providers are available in India, that have impressive portfolio and have successfully handled utility to innovative EPC solar plat installations with ease. With their help, it will be easy for the solar seekers in India to move forward in adopting green energy, contributing to the national solar mission.