The global transition to solar depends not only on the efficiency of the photovoltaic panels themselves, but also on the structural integrity, cost-effectiveness and longevity of the systems that hold them in place. Aluminium extrusion has emerged as the fundamental technology for these mounting systems, offering an unparalleled combination of engineering benefits and economic advantages. This manufacturing process is not just an option, but a critical enabler, allowing for the rapid deployment and reliable performance of solar arrays worldwide. This article delves into the specific advantages, common profiles, and manufacturing processes that make aluminium extrusion indispensable to the solar industry.
Advantages of Aluminium Extrusion in Solar Panel Mounting Systems
Lightweight yet Strong:
Aluminium extrusions offer a high strength-to-weight ratio, providing durability and stability without adding excessive weight to the structure, making installation easier and safer.
Corrosion Resistance:
Aluminium naturally forms a protective oxide layer, which makes it highly resistant to corrosion and weathering—an essential feature for outdoor solar installations exposed to the elements.
Customizability and Flexibility:
The extrusion process allows for the precise fabrication of components with complex profiles, enabling custom designs tailored to specific mounting configurations and site requirements.
Ease of Fabrication and Assembly:
Aluminium extrusions can be easily cut, drilled and machined, simplifying the assembly process and reducing installation time and cost.
Aesthetic Appeal:
Aluminium provides a sleek, modern look and can be finished with a variety of coatings or anodization to enhance appearance and durability.
Recyclability:
Aluminium is 100% recyclable without loss of properties, aligning with sustainability goals and reducing environmental impact.
Thermal Conductivity:
Good thermal properties help dissipate heat, which can improve the efficiency and longevity of solar panels.
Solar panel mounting systems
Common Aluminium Extrusion Profiles in PV Mounting Systems
Different profiles are designed for specific functions within the mounting system:
- Solar Panel Frame: The actual frame that holds the glass and solar cells is almost always a custom aluminum extrusion designed to snap-fit or mechanically interlock with the panel laminate.
- Main Rails (Longitudinal Beams): These are the primary beams that run the length of the array. Solar panels are clamped onto these rails. They are typically robust profiles with integrated T-slots.
- Cross Rails (Purlin Beams): In some systems, especially on flat roofs, cross rails provide additional support between the main rails.
- L-Feet and T-Feet (Mounting Brackets): These connect the main rails to the roof (for rooftop systems) or to the ground-mounted foundation. They tend to be heavy-duty extrusions designed for high load-bearing capacity.
- Mid and End Clamps: These are smaller, precision extrusions that hold the edges of the solar panel to the rail. They are designed to be strong, secure and non-abrasive to the panel frame.
- Cable Management Channels: Simple U-shaped or C-shaped extrusions that snap onto the main rail to hide and protect wiring
The Aluminium Extrusion Manufacturing Process for PV Mounts
1. Billet Heating: An aluminium alloy billet (commonly 6000-series, like 6061 or 6063, for its good strength and corrosion resistance) is heated to 400-500°C.
2. Extrusion: The softened billet is pushed through a steel die with the desired profile shape using a hydraulic ram.
3. Quenching & Cooling: The newly formed profile is rapidly cooled to maintain its mechanical properties.Stretching & Straightening: The long extruded profile is stretched to correct any twisting or distortion.
4. Cutting to Length: The profile is cut into standard lengths for shipping and handling.
5. Heat Treatment (Aging): The profiles are aged in an oven to achieve their final strength (T5 or T6 temper). Surface Finishing: This is a critical step for PV mounts:
6. Anodizing: Creates a hard, durable, and corrosion-resistant oxide layer. Can be clear or colored.
7. Powder Coating: Provides a thick, uniform, and colorful protective layer that is highly resistant to chipping, scratching, and UV degradation.
Conclusion
Aluminium extrusion is not just a convenient option for solar panel mounting systems; It’s an enabling technology. Its unique combination of light weight, strength, corrosion resistance, and unparalleled design flexibility allows the creation of cost-effective, durable, and highly efficient mounting solutions that are essential to the global adoption of solar power. The ability to create integrated, modular systems directly translates to faster installation and lower overall costs for solar projects.