Effect of High Temperatures on Solar Panel Efficiency
- Temperature Increase and Efficiency Drop: Solar panels are rated for optimal performance at 25°C (77°F), but their efficiency decreases as temperatures rise. For every degree Celsius above this optimal temperature, solar panel efficiency typically drops by 0.3% to 0.5%. This can result in a substantial loss of power output, with losses ranging from 10% to 25% in very hot conditions.
- Voltage Reduction and Current Increase: Higher temperatures cause a decrease in the open-circuit voltage (Voc) of solar cells, which is crucial for power production. This decrease is about 2.2 mV per °C for silicon cells. Although the short-circuit current (Isc) slightly increases with temperature, this increase is outweighed by the voltage drop, leading to an overall reduction in power output.
- Increased Recombination and Resistance: High temperatures also lead to increased recombination rates of charge carriers within the semiconductor material, reducing the efficiency of the photovoltaic conversion process. Additionally, there’s an increase in internal resistance, which further reduces efficiency.
Strategies to Mitigate Temperature Effects
- Proper Installation: Mounting solar panels a few inches above the roof to allow airflow can help cool them.
- Reflective Materials: Using solar panels with light-colored, reflective materials can reduce heat absorption.
- Electronic Component Placement: Keeping electronic components in a shaded area can help maintain their operational temperature.
- Cooling Techniques: Implementing cooling systems, such as evaporative cooling in hot climates, can significantly improve efficiency.
High temperatures reduce solar panel efficiency, but strategies exist to minimize these effects and optimize energy production, especially in hot climates.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-does-high-temperature-affect-the-efficiency-of-solar-panels/
