Solar energy tracking algorithms are essential for optimizing the energy output of photovoltaic (PV) modules by ensuring they are oriented optimally towards the sun throughout the day. The two primary tracking parameters used in solar energy tracking algorithms are azimuth and elevation.
Azimuth Tracking:
Azimuth tracking involves adjusting the orientation of the PV module in the horizontal plane, typically measured clockwise from true north. The goal is to maximize the incident solar radiation on the surface of the PV module. The azimuth angle changes throughout the day as the sun moves from east to west.
Algorithms for azimuth tracking can be based on various methods, including astronomical equations or trigonometric calculations. Some common approaches include:
a. Solar Position Algorithms: These algorithms use equations based on solar position models (e.g., SPA algorithm) that determine the sun's position in the sky at any given time and location. By comparing the sun's position to the PV module's location, the azimuth angle can be calculated.
b. Rule-Based Algorithms: Rule-based algorithms use predefined rules and tables to determine the azimuth angle based on the date, time, and location. These rules consider the sun's path throughout the year and approximate the azimuth angle accordingly.
Elevation Tracking:
Elevation tracking involves adjusting the inclination or tilt angle of the PV module with respect to the horizontal plane. The goal is to optimize the angle of incidence of sunlight on the PV surface to maximize energy absorption. The elevation angle changes throughout the day as the sun's altitude varies.
Elevation tracking algorithms also rely on solar position models to calculate the sun's elevation angle at any given time and location. Common approaches include:
a. Solar Position Algorithms: Similar to azimuth tracking, these algorithms use solar position models to calculate the sun's elevation angle based on date, time, and location.
b. Light Sensors: Some systems use light sensors or pyranometers to directly measure the intensity of sunlight falling on the PV module. This information is used to adjust the elevation angle in real-time.
c. Tracking Algorithms with Optimization: More advanced tracking algorithms may incorporate optimization techniques, such as maximizing the power output or energy efficiency of the PV system. These algorithms may use predictive models and feedback control systems to dynamically adjust the elevation angle.
It's important to note that while solar tracking algorithms can significantly improve energy generation, they also add complexity and cost to the PV system. Therefore, the decision to implement tracking technology depends on factors like the specific location, energy demand, and budget constraints. Fixed-tilt installations may be more suitable for certain applications where the added benefits of tracking do not justify the increased cost and maintenance requirements.