The heat dissipation design of a photovoltaic fixture plays a crucial role in the stability of its photoelectric conversion. Its core principle is to ensure the coordinated operation of the photovoltaic panels and lighting modules by controlling temperature fluctuations, thereby maintaining long-term stable system output.
The photovoltaic fixture's photoelectric conversion process relies on the photovoltaic panels converting light energy into electrical energy, which is then powered by the driver circuit to power the lighting module. During this process, the conversion efficiency of the photovoltaic panel is strongly negatively correlated with temperature. As the panel temperature rises, the carrier recombination rate within the semiconductor material increases, causing the open-circuit voltage to drop, directly weakening the photoelectric conversion capacity. Furthermore, the LED light source in the lighting module also generates heat during emission. If the heat dissipation design is inadequate, the increased LED junction temperature can cause light efficiency degradation, wavelength shift, and even accelerate material aging. Therefore, the heat dissipation design must simultaneously address both cooling the photovoltaic panel and maintaining temperature stability for the LED light source, creating a two-way protection mechanism.
The heat dissipation design of photovoltaic panels requires consideration of both material and structural aspects. Traditional crystalline silicon modules can reduce thermal resistance by optimizing the packaging process, such as using high-thermal-conductivity backsheet materials and EVA films to accelerate heat transfer to the environment. New perovskite modules, on the other hand, must address the inherent thermal stability of the material, typically by adding a thermal buffer layer or using a flexible substrate to distribute stress. At the system level, the mounting angle and spacing of the modules also influence heat dissipation. An angled mounting enhances airflow, while maintaining ample clearance between modules prevents heat accumulation. Furthermore, some photovoltaic fixtures incorporate active cooling devices, such as micro-fans or heat pipes, to accelerate heat dissipation through forced convection, but this requires a trade-off between energy consumption and cost.
LED light source heat dissipation design focuses more on optimizing the heat conduction path. Heat generated by high-power LED chips must be transferred step by step through a metal substrate (such as an aluminum-based PCB), thermal grease, and heat sink fins. The design of the heat sink fins must balance surface area and air flow. Too dense fins can obstruct airflow, while too sparse fins can prevent adequate heat dissipation. Some high-end products utilize liquid cooling or phase-change materials to absorb heat through changes in material state, but these solutions are costly and primarily used in specialized scenarios. Natural convection remains the dominant cooling method for photovoltaic fixtures, so simulation software is required to optimize the fin shape and layout to ensure efficient heat dissipation without external interference.
The impact of thermal design on system stability is also reflected in its extended service life. When photovoltaic modules operate in high-temperature environments, their encapsulation materials (such as EVA and backsheets) age faster, leading to delamination and yellowing, which in turn reduces light transmittance and insulation performance. When LED light sources are exposed to long-term high temperatures, the phosphors gradually degrade, accelerating the rate of luminous efficacy degradation. This also increases the risk of fatigue fractures in solder joints and gold wires due to thermal expansion and contraction. By keeping the operating temperatures of the modules and light sources within reasonable ranges (e.g., below 85°C for photovoltaic modules and below 120°C for LED junction temperatures), thermal design can significantly slow material degradation and ensure stable system operation for years or even decades.
The thermal design of photovoltaic fixtures also needs to balance environmental adaptability with energy efficiency. In high-temperature regions, more weather-resistant materials and more aggressive heat dissipation strategies are required; in low-temperature regions, the risk of short circuits caused by condensation must be prevented. Furthermore, the energy consumption of heat dissipation devices should be factored into overall system efficiency assessments to avoid offsetting the benefits of photovoltaic conversion due to excessive heat dissipation. For example, if the power consumption of active cooling fans exceeds 1% of the photovoltaic system's gain, the design should be re-optimized.
The heat dissipation design of photovoltaic fixtures is critical for ensuring stable photovoltaic conversion. Through material innovation, structural optimization, and environmental adaptation, efficient synergy between photovoltaic modules and LED light sources can be achieved, ensuring long-term stable system operation under complex operating conditions and providing reliable technical support for clean energy lighting.
