Solar panel degradation refers to the natural reduction in the performance of solar panels over time. This is a gradual process influenced by several factors, including environmental impacts, material quality, and solar panel manufacturing technology.
What causes solar panel degradation?
Environmental factors:
- UV radiation: Constant sunlight exposure can damage solar panel materials, such as plastic and insulation, over time.
- Temperature fluctuations: Daily and seasonal temperature changes can cause stress in the solar panel structure, leading to micro-damages.
- Extreme weather conditions: Hail, wind, snow, and rain can accelerate material wear and tear.
Material quality: Lower quality materials used during manufacturing can result in faster performance degradation. Quality manufacturers use premium materials that slow down the degradation process.
Thermal fatigue: Repeated heating and cooling cause materials to expand and contract, leading to mechanical damage in the long run.
PID (Potential Induced Degradation): This is a specific degradation process that can be caused by the voltage difference between the solar panel and the ground, reducing the module's efficiency.
LID (Light Induced Degradation): Degradation that occurs during initial use, when the solar panel material stabilizes under the influence of sunlight.
Extent of degradation
Average degradation rate: Solar panel performance typically decreases by 0.5–1% annually. This means that over a 25-year lifespan, solar panel performance usually falls to 80–85% of its nominal capacity.
Premium solar panels: For higher quality panels, annual degradation can be as low as 0.3%, ensuring greater efficiency in the long term.
Guaranteed performance: Most manufacturers guarantee that the performance of solar panels will still reach 80-90% of their nominal capacity after 25 years.
How to reduce degradation?
Choosing quality solar panels: Using panels made by premium manufacturers can slow down the degradation process.
Expert installation: Improper installation can increase the risk of degradation (e.g., mechanical damage, inadequate ventilation).
Regular maintenance: Cleaning and regular inspection of solar panels help maintain optimal performance. Removing shading, dirt, or snow minimizes efficiency loss.
PID protection: Grounding and insulation solutions for inverters can reduce degradation caused by PID.
Proper installation site selection: To minimize extreme weather conditions, it is advisable to install solar panels in a protected but well-lit area.
Degradation and lifespan
- Long-term performance: The expected lifespan of solar panels is 25-30 years, during which their performance gradually decreases, but they continue to generate useful energy.
- Further use: After 25 years, operating solar panels are usually able to provide 70–80% of their original performance, so they can be economically used further.
Summary
Solar panel degradation is a natural process in which the performance of solar panels gradually decreases over time. Although unavoidable, selecting appropriate solar panels, professional installation, and regular maintenance can help minimize its effects. Understanding and managing degradation ensures that solar panel systems operate efficiently and economically in the long term.