Introduction
Most solar panels consist of silicon photovoltaic (PV) cells that are protected by glass panels and held together with a metal frame. These materials are similar to those that make up the Windows and bezels of cars - to understand the heat of solar panels, think of a car parked in a parking lot on a hot summer day. The Windows and borders will be hot to the touch, but pose little risk of fire.
If the surface temperature of the solar panel reaches this high, the efficiency of the solar panel will decrease. But also keep in mind that solar panels are made of highly durable materials that can withstand extreme outdoor conditions - from freezing weather in winter to scorching heat in summer. In addition, the exact temperature of your solar panels will depend on factors such as air temperature, geographic location, direct sunlight, and roofing materials. How an experienced solar charging panel manufacturer selects and installs solar panels to minimize any minimal impact of heat on solar panel efficiency.
The effect of temperature on the efficiency of solar panels
Home solar panels are tested at 25 °C (77 °F), so the solar panel temperature is usually between 15 °C and 35 °C, during which time the solar cell will produce maximum power generation efficiency. However, the temperature of the solar panel can reach as high as 65 °C (149 °F), at which point the efficiency of the solar cell will be hampered.
Users considering solar panels often wonder, "Can solar panels overheat?" As with any other electronic device, the performance of solar panels does decline as the temperature increases - the laws of thermodynamics tell us that power output decreases as heat increases, and this also applies to solar panels. Therefore, the increase in temperature means that the output of the solar panel is reduced, which is called the "temperature coefficient".
The temperature coefficient is an assessment of the sensitivity of a product to temperature, expressed as a percentage per degree Celsius. For example: if solar panels have an efficiency of 17% and a temperature coefficient of -0.45, they lose 0.45% of their efficiency for every 1 degree increase above 25 °C. If the surface temperature of your roof rises to 30 °C (86 °F), the efficiency of the solar panels will drop to 16.7%. If it increases to 35 °C (95 °F), the efficiency drops to 16.3%.
At high temperatures, the ambient temperature of the bus box and inverter plus the heat emitted by the operation of the equipment is far higher than the outdoor temperature. In the case of carrying near full load, if there is no good heat dissipation environment, it will accelerate the decay and aging of the electronic components in the equipment.
Secondly, the dust accumulation, bird droplet, shadow and other foreign bodies on the surface of the photovoltaic module, accompanied by high temperature weather, easy to cause changes in the current and voltage of a single panel in the photovoltaic module, resulting in local temperature rise of the photovoltaic module on the surface of the thermal spot effect, seriously damaging the operation of the photovoltaic module.
When the ambient temperature is 35-40 ° C, the backplane temperature of the photovoltaic module can reach 50-70 ° C, and the actual internal component temperature of the photovoltaic module is even higher. After exceeding the rated operating temperature, the photoelectric conversion efficiency will decrease proportionally, thus affecting the power generation efficiency.
How to offset solar panel overheating?
No matter which panel is used, there will always be some loss of power output due to heat. However, there are several ways to mitigate the effects of high temperatures on solar panels. Solar panels are also usually installed a few inches above the roof, and there is actually a airflow space underneath to help carry heat away from the solar panels. One more thing, the temperature at which solar panels generate maximum conversion efficiency is 23°C.