How Solar panels work in different weather conditions?

Written by Tania Tahseen
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Solar energy is a clean source of electricity that can be harnessed through various ways, one of them being solar panels. There are certain limitations associated with this type of clean energy. One such limitation is dependency of solar panels on weather for energy generation. How does rain affect solar panels or what will be the effect of clouds on solar panels? These questions are often a cause of concern for many people who want to install solar power plants.

Solar panels are designed to work under different weather conditions. However, not everyone is aware of the fact that solar panels can still perform well even when it is cloudy or if there is rainwater on them. The common misconception is that solar panels only work well under sunlight, however, they do require a minimum amount of sunlight before they start working.

Addressing such doubts and misconceptions through this article will help you understand better how you can use solar systems in different weather conditions to increase their efficiency and performance.

Here is what you need to know about how varying weather conditions can affect solar PV cell performance:

Extreme summer day

Solar panels work well in a wide range of weather conditions. But there is one common misconception that people assume is solar panels tend to work well under high temperatures. Even though the amount of sunlight hitting on the solar panel is directly proportional to the power output of the panel. In other words, the increasing temperature of the solar panels can have a decreasing effect on efficiency. Solar panel temperature usually ranges from 15°C to 35°C, during which they produce maximum power. On the manufacturer's datasheet, this loss is shown as a temperature coefficient versus power. The output power of a solar panel will decrease by half of a percent for every degree the temperature rises above 25°C because resistances within most solar cells and modules (e.g. bypass diodes) increase with temperature.

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As we can see from the graph, with the rise in temperature Voltage and power of the module will decrease and there will be an increase in the flow of electricity. The greater will be the flow of current, the higher will be the losses.

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Power curve on a hot summer day(19kW, Faridabad)

Cloudy days and Rainy season

While any solar energy installation will ultimately be affected by the weather, clouds are not really the obstacle they appear to be. Many people think solar panels work best in sun-blasted regions with few or no clouds. That’s not quite true. Cloudier days create an estimated power drop-off of about 10 to 25 percent from what you see on a sunny day.

Most solar panels will work just fine in a brief rainstorm. However, if it rains for more than a few hours, it will have an impact on your system's output. The rain will have no measurable effect on the panels themselves. However, rain clouds can reduce production by blocking sunlight from reaching the panels. Thus reducing the generation for the day.

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Power curve on a partly rainy day(19kW, Faridabad)

Winter Season

The photovoltaic panels generate electricity from sunlight, not from air temperature. This means that the panels will work in cold weather even when the ambient temperature is very low. Due to the sun rising every day in cold climates, solar power can be used even in extremely cold weather.

There are certain places in India with snowfall in some parts of the year. Will solar work in this weather condition? Solar panels are designed to work in all weather conditions. The only factor that can affect a solar installation is snow accumulation, which can reduce production due to shading. Snow will, however, melt quickly off your panels. Depending on the weather after a snowstorm and the tilt of your panels, heavy snowfalls will melt and slide right off your panels within minutes.

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Power curve on coldest day(19kW, Faridabad)

The Ideal temperature for solar panels

Imagine a perfect day for solar panels. It is sunny and the sky is clear and blue. How about the temperature? Is it cold or is it warm?

Similarly to other electronics, solar panels work better in cold temperatures, enabling them to produce more voltage, and therefore more electricity. As the temperature rises, the panel produces less voltage and becomes less efficient, resulting in less electricity.

What is the impact of temperature on production? To find this out, you can take a look at the specification sheet for different panels. The numbers on these sheets are based on various tests conducted by the manufacturer. In general, for each degree above 25 degrees centigrade (known as standard testing condition, or STC), your panel will become one percent less efficient. For each degree below 25 degrees centigrade, it will become one percent more efficient up to a certain temperature(depending on location).

In the winter, solar panels may be more efficient, but they don't necessarily produce more electricity than they do in the summer. The extreme weather conditions in summer might reduce the efficiency of solar panels. But they are likely to produce more electricity than in colder months as they get more sunlight during summers(due to longer day hours).

Solar energy does have its limitations in areas where the weather is harsh. However, solar panels can still produce electricity even if it is cloudy or rainy outside. Solar will work with a reduced efficiency be it a snowfall or extreme heat wave.

The good news is that your solar will return to its maximum output when the sun shines. A properly installed solar energy system will provide you with excellent results even in bad weather.

Choosing the right solar company is necessary so that your solar system can withstand harsh weather conditions. Do contact us if you want the best quality and services for your solar system.