Solar Array Mounts: The Foundation

Solar array mounts serve as the crucial framework that holds solar panels in place, ensuring they are angled to capture the maximum amount of sunlight. Rooftop installations are popular for homes due to space efficiency and the aesthetic appeal of integrating solar power systems with existing structures. These mounts must be securely attached to the roof, considering factors such as roof type, pitch, and load-bearing capacity.

Ground-mounted systems are more common in solar farms or residential settings where roof space is inadequate or unsuitable. These mounts require a clear and level area and may need to be more robust to withstand environmental stresses such as wind and snow.

The geographical location is a significant factor in the mount type since it determines the sun's angle and the sunlight's intensity and duration. Additionally, local climate conditions such as wind speed, snow load, and the likelihood of extreme weather events are critical considerations, as these will dictate the sturdiness and design specifics of the mounts to ensure longevity and durability.

Fixed Mount

The most basic mount type is the fixed mount, which keeps the solar panels stationary. These are often angled at a certain degree based on the location's latitude to optimize the sunlight received throughout the year. Fixed solar panel mounts are installed on roofs through a process that usually follows these steps:

Site Assessment: Professionals initially assess the roof to determine its suitability. This involves checking the roof's structure, material, angle, and available space and identifying any obstacles that might cast shade on the panels.

Design and Layout: Based on the assessment, a layout is designed to maximize sun exposure while considering the weight distribution and the roof’s load-bearing capacity. The ideal angle is calculated according to the location's latitude and local regulations or recommendations.

Mounting Hardware Installation: Once the layout is designed, the next step is to install the mounting hardware. This typically involves securing footings to the roof, the base to which the mounts will attach. For roofs that can be penetrated, the footings are often bolted directly into the rafters for stability. Non-penetrative systems may be used for metal or rubber roofs.

Sealing: Proper sealing is crucial to prevent water leakage through the bolt holes. Installers will use flashing and sealants around the base of the mounts to ensure the roof remains watertight.

Attaching the Mounts: The mounts, the support structures, are then attached to the footings. These must be strong enough to support the weight of the panels and resist environmental loads such as wind and snow.

Panel Installation: With the mounts in place, the solar panels can be attached to the mounting structure. According to the system design, panels are secured with clamps or bolts and connected electrically in series or parallel.

Wiring and Inverter Connection: The electrical wiring is then run from the solar panels to the inverter, which converts the direct current (DC) produced by the panels into alternating current (AC) that can be used by the home or fed into the electrical grid.

Final Inspection and Commissioning: A final inspection is carried out to ensure everything is installed correctly and operates as it should. Once approved, the system is commissioned and begins to generate electricity.

Tracking Mount

For those seeking more efficiency, tracking mounts are available that move the panels to follow the sun’s path from east to west during the day. Some tracking systems are simple, single-axis trackers that pivot on one axis, while more advanced dual-axis trackers can also adjust the tilt of the panels to compensate for the sun’s seasonal shifts in the sky.

Single-Axis Trackers: These trackers rotate on one axis, usually aligned north-south, allowing the panels to arc from east to west in synchronization with the sun's daily movement. Single-axis trackers are generally less complex and less expensive than their dual-axis counterparts. Depending on the geographical location, they can significantly increase the panels' energy output, often by up to 25-35% more than fixed mounts.

Dual-Axis Trackers: These systems offer two degrees of motion. In addition to rotating from east to west, they can tilt the panels' angle to account for the sun's elevation changes throughout the year. By adjusting for both daily and seasonal variations in the sun’s position, dual-axis trackers can boost the energy yield of solar panels even further, often up to 35-45% more than fixed mounts, though this can vary widely based on specific regional solar conditions.

Both types of trackers use either a passive or active mechanism to move.

Passive trackers: These systems use a low boiling point compressed gas fluid that moves from one side of the tracker to the other as it heats up and cools down, tilting the tracker as it goes. This system relies on the sun's heat and does not require additional power sources.

Active trackers: Active trackers use motors and gears to move the panels throughout the day. They are often controlled by a programmable logic controller (PLC) that uses sensor data or a pre-programmed algorithm based on the sun's expected position.

Conclusion

The choice between single-axis and dual-axis trackers is influenced by several factors, including the cost, the system's complexity, maintenance requirements, and the specific energy goals of the installation. While tracking systems do increase energy production, they also involve more moving parts, which can lead to higher maintenance requirements and costs. In many cases, the increase in energy output can offset these costs over the system's life.