Installing a photovoltaic (PV) system is a process that requires not only knowledge of technology and technical standards but also precise execution and experience with support structures. Mistakes made during installation can affect the system’s efficiency, durability, and safety. Below are 11 of the most common mistakes related to the installation of PV panel structures and how to avoid them.
1. Insufficient Soil Analysis
One of the key elements of designing a ground-mounted PV installation is soil analysis. Failure to conduct a proper geotechnical study can lead to structure settling, system instability, and even damage. Low-load-bearing soils, such as sandy, clayey soils, peatlands, or areas with high groundwater levels, can be particularly problematic.
How to avoid it:
- Conduct a detailed geotechnical analysis, considering soil structure, load-bearing capacity, and the depth of stable soil layers.
- In regions with unstable soil, use point foundations, screw piles, or root anchoring systems that distribute the load over a larger area.
- Perform pull-out tests at the installation site to determine the maximum dynamic load that the anchors or piles can withstand.
2. Incorrect Tilt Angle of Photovoltaic Panels
In Poland, the optimal tilt angle for PV panels ranges from 30° to 40°, depending on geographic location. An angle that is too low can lead to dirt accumulation on the panel surface, reducing efficiency, while an angle that is too high decreases sunlight absorption.
How to avoid it:
- For ground-mounted systems, use adjustable structures that allow the panel angle to be adapted for different seasons.
- On roofs, adjust the tilt angle to match the roof slope using appropriate mounting systems.
3. Errors in Support Structure Installation
The support structure is the foundation of the PV system’s stability. Poor installation, such as improper assembly, using the wrong materials, or lack of anti-corrosion protection, can lead to structural deformation, system damage, and reduced lifespan. It is crucial to choose materials suited to local environmental conditions, such as humidity, salinity, or exposure to aggressive chemicals.
How to avoid it:
- Material Selection:
- Magnelis® Coated Steel – Exceptional corrosion resistance, particularly in environments exposed to moisture, salinity, or ammonia (e.g., near livestock farms).
- ZAM®-EX – A zinc, aluminum, and magnesium alloy offering high anti-corrosion protection, ideal for PV structures in harsh weather conditions.
- PosMAC® – Steel coated with a magnesium-aluminum alloy, highly resistant to corrosion, even in aggressive environments like saline soils or areas prone to acid rain.
- Hot-Dip Galvanized Steel – A traditional solution offering good corrosion resistance, suitable for moderate environmental conditions, but may require additional protection in high-humidity areas.
- Aluminum – Lightweight, corrosion-resistant material that does not require additional protective coatings.
- Reinforced Plastics – Composites, such as glass-fiber-reinforced polyamide, resistant to UV radiation, moisture, and corrosion, typically used for auxiliary elements like brackets and covers.
- Environmental Adaptation:
- Conduct an analysis of the environment’s corrosiveness, including soil composition, groundwater, and salinity levels.
- In areas with high chemical aggression (e.g., near industrial sites), use materials with increased resistance, such as aluminum or advanced anti-corrosion coated steel.
- Proper Installation:
- Use tools like torque wrenches to ensure bolts are tightened according to manufacturer specifications.
- Distribute loads evenly on the structure, especially in rooftop installations, to avoid roof deformation.
4. Lack of Grounding for the Structure and Panels
Lack of grounding for the support structure and PV panels poses a significant safety risk. In the event of power surges or lightning strikes, improper grounding can cause system damage, fires, or electric shock hazards.
How to avoid it:
- Ground the system according to standard PN-EN 62305 and manufacturer recommendations.
- Use grounding cables and dedicated clamps to ensure electrical connections between all metal parts of the structure.
5. Panel Damage During Installation
PV panels are prone to mechanical damage that can reduce their efficiency or render them non-functional. Common issues include cracks, surface scratches, and micro-damage invisible to the naked eye.
How to avoid it:
- Use specialized clamps and tools to handle panels.
- Avoid walking on panels or exerting excessive stress on their structure during installation.
6. Panel Delamination
Delamination, or the separation of the panel’s layers, is often caused by moisture, high temperatures, or incorrect installation.
How to avoid it:
- Install panels according to manufacturer guidelines, ensuring proper ventilation.
- Use sealing in areas exposed to direct water contact.
7. Improper Cable Management
Poor cable routing, lack of UV protection, or mechanical damage can impact the system’s performance.
How to avoid it:
- Use solar cables resistant to UV rays, moisture, and mechanical stress.
- Organize cables neatly with protective covers and mechanical safeguards.
8. Inductive Loops in the Installation
Improper cable routing can create inductive loops that disrupt system performance and increase energy losses.
How to avoid it:
- Route power and return cables close together to avoid creating loops.
9. Lack of Proper Panel Ventilation
PV panels generate heat during operation. Insufficient ventilation can cause overheating, reducing efficiency and shortening lifespan.
How to avoid it:
- On roofs, maintain a gap of at least 10 cm between the panels and the roof surface.
- For ground-mounted systems, ensure the structure is high enough to allow natural air circulation.
10. Neglecting Maintenance and Monitoring
Lack of regular inspections and maintenance can lead to decreased efficiency and serious malfunctions.
How to avoid it:
- Regularly check the condition of the panels, cabling, and support structure.
- Use monitoring systems to track system performance in real time.
11. Poor Installation Design
A poorly designed installation can lead to reduced system efficiency, shading issues, or insufficient protection from weather conditions.
How to avoid it:
- Design installations considering local factors such as sunlight exposure, snow load, and wind directions.
- Hire experienced designers and certified contractors.
Conclusion
Installing a photovoltaic system requires precision, thorough preparation, and the use of high-quality materials. Avoiding common mistakes improves the system’s efficiency, durability, and safety. By conducting proper analysis, paying attention to detail, and working with professionals, the installation will operate reliably for many years.
