Key Parameters in Solar Tracker Selection

As a solar tracker manufacturer, we frequently communicate with clients about various parameters during the project planning stage. Determining these parameters is the foundation of solar tracker selection. Below is a brief overview of the key parameters and their significance.

Capacity

This refers to the capacity of the project, usually expressed in kW or MW (e.g., 100 kW, 5 MW).

It determines the procurement scale of solar trackers and sets the overall direction for equipment selection. Small-scale projects often adopt modular, compact solar trackers, while large utility-scale plants typically use mass-produced models.

Location-longitude & latitude

This is the geographical location of the project, preferably with precise coordinates (longitude and latitude).

It defines the sun path (azimuth at sunrise/sunset, solar altitude), irradiation distribution, and has implications for tracking algorithms (azimuth range, tilt angle strategy). Altitude data is also useful for wind load and structural design evaluations.

Terrain

This refers to the topography of the site, including Flat land (farmland) / Slope / Mountain / Rooftop.

Terrain influences the type of foundation and may require segmented designs. Sloped or mountainous sites often need customized supports. Rooftop projects require strict consideration of weight, wind load, waterproofing, leakage prevention, and fire resistance, typically favoring lightweight, compact solar trackers.

For sites with significant slopes or undulating terrain, consultation with the project designer is strongly recommended.

PV module dimensions

The length × width × thickness (mm) and weight (kg) of each module.

Module dimensions are closely related to wind load. Larger modules increase row weight and wind-facing area, demanding stronger bending and torsional resistance.

Panel power

The rated power of a single solar panel (W or Wp, e.g., 540W, 600W).

This determines the installed capacity per row (kW/row).

String

The number of panels installed along the horizontal row of a tracker.

This directly affects main beam stress, deflection, torsional stiffness, and drive torque requirements.

While manufacturers can provide recommendations, the exact row length must be determined through on-site surveying, considering terrain, dimensions, and layout conditions.

Power Supply

Whether the solar tracker controller and actuator are powered by the grid (on-grid) or by on-site PV modules with batteries (off-grid).

Grid power ensures stable drive and is suitable for high-power motors. PV-powered systems are used in remote areas without grid access, but require careful consideration of capacity, matching with the controller, and reliability during long cloudy/rainy periods and nighttime.

Wind load

The design wind speed of the site, typically expressed in m/s or km/h. It is important to specify whether it refers to average wind speed or gust, as well as the measurement height (commonly 10 m). Different standards define return periods differently, usually not less than 20 years.

This parameter is critical for structural strength, section dimensions, beam thickness, hinge/gearbox specifications, drive torque, and survival stow design. Storms and gusts may also determine whether stow strategies, deceleration, or locking mechanisms are required.

Snow load

The design snow load on the ground or module surface (kg/m² or kN/m²).

This affects section size, support spacing, connector safety margins, minimum ground clearance, as well as snow-shedding strategies and tilt angle limits.

Clearance

The minimum gap between the lower edge of the solar panels and the ground (mm or m).

This impacts row-to-row shading calculations. In agricultural sites, clearance must consider crop height, livestock passage, and farm machinery operation. In snowy regions, insufficient clearance can reduce generation and increase structural loads, while excessive clearance raises construction costs.

Foundation

The foundation system used to secure the trackers, such as cast-in-place concrete piles, driven steel/pipe piles, or PHC piles.

This determines installation method, cost, construction timeline, and bearing/uplift capacity. Since it is closely tied to geotechnical reports (soil report, SPT results, bearing capacity, groundwater level), consultation with project designers is recommended.

Conclusion

In practice, the parameters required for solar tracker design go beyond the 11 items listed above—these are simply the most fundamental data points needed during project discussions. These parameters not only define the mechanical strength and suitability of the system but also directly affect power generation efficiency and overall project economics. Therefore, a thorough understanding and proper configuration of these parameters are key to ensuring project success.