Does Weather Affect Solar Energy Production?

Installing a solar power system for your home or business is one of the best investments you can make. Even just a small solar array can make a significant difference in your electricity bills. With a larger array and a solar battery pack to store the excess energy your solar panels produce, you may never have to pay for electricity again. If you want more control during storms and outages, consider solar battery storage options as part of your system design.

Despite all the advantages of solar power, many people remain hesitant to adopt it due to myths and misconceptions surrounding its impact on solar production in relation to the weather. While certain weather conditions can affect solar efficiency and energy production, modern solar systems are highly efficient and can continue to produce power even in adverse weather conditions. The key is understanding what changes are normal, what changes are seasonal, and what changes may signal that your system needs attention.

Weather does not have to be a mystery. In most cases, when you see production dip, there is a clear reason, including reduced sunlight, temporary shading, dirty panels, or shorter winter days. When you know how weather affect solar energy production, you can set realistic expectations, protect output, and make smarter choices about storage, maintenance, and monitoring.

Does weather affect solar energy production?

Yes, weather affect solar energy production in predictable ways, mostly by changing how much sunlight reaches your panels and how efficiently the panels operate. The good news is that “less efficient” rarely means “not working.” Most weather impacts are temporary, and a well-designed system is built to produce reliably across the seasons. If you want a clearer picture of what your system is designed to do, our solar services we offer include guidance on sizing, performance expectations, and long-term support.

Temperature

One of the most common myths is that solar panels don’t work in cold weather, which is definitely not the case. Solar panels rely on the light from the sun, not its heat, to produce energy. That means cold has zero effect on solar efficiency. The primary reasons solar panels may generate less heat overall during the winter months are that there are fewer hours of sunlight and the panels may occasionally be covered with snow.

While cold temperatures do not affect solar production, higher temperatures do reduce the efficiency of solar panels. When the sky is clear, solar panels can operate at nearly full capacity as long as the temperature does not exceed 77 degrees. Anything above this and solar efficiency usually decreases by approximately 1% per degree.

That drop is usually more noticeable on very hot, bright days because panels are receiving strong sunlight while also operating at higher temperatures. In other words, heat can reduce efficiency even when solar conditions look “perfect,” which is one reason summer production is not always as high as people assume.

Clouds and how weather affect solar energy production

Another misconception is that solar panels only produce energy when the sky is bright blue and fully clear. Cloudy weather does indeed impact solar efficiency by reducing the amount of sunlight that reaches the panels. Nonetheless, a solar system will still generate power even on extremely overcast days. On partially cloudy days, solar panels typically operate at around 50% of their total capacity. If there’s much heavier cloud cover throughout the day, their production could drop to as low as 10-20% of the total capacity.

What many people do not realize is that changing cloud cover can also create spikes and dips in output throughout the day. That variability is normal, and it is one of the clearest examples of how weather affect solar energy production in real time. If your monitoring shows production bouncing up and down on a partly cloudy day, that pattern usually matches what the sky is doing, not a system problem.

Rain

Rain impacts solar production in several different ways. The first is that the cloud cover reduces the amount of light that reaches the panels. Rain droplets also scatter light, which can result in fewer photons reaching the panels. Water on the solar panels also reflects some of the light. While solar systems produce less energy during rainstorms, rainfall is still beneficial overall. Whenever it rains, the water washes away all the dirt and dust from solar panels, allowing them to work more efficiently once the weather clears.

Light rain can also reduce airborne dust and pollen levels in the short term, which helps keep panels cleaner. If you live near roads, construction, farms, or areas with heavy pollen seasons, the “cleaning effect” of rain can make a noticeable difference once the sky clears.

Snow and how weather affect solar energy production

If there’s only a light dusting of snow on your solar panels, some photons will still reach the panels and result in them producing at least some energy. If your solar panels are fully covered in snow, they won’t produce any power. The good news is that the sun melts snow off solar panels fairly quickly, even in cold temperatures. The fact that solar panels are angled also means that snow will promptly slide off them as soon as it starts melting.

There is considerable debate about whether to clean snow off solar panels. Cleaning snow off ground-mounted solar panels is easy, as long as you’re careful not to damage them. You can use a foam roof rake or snow brush with a telescoping handle to try to clean rooftop solar panels. However, most experts recommend against doing this due to the potential for the panels to get scratched or damaged, which would render them less efficient.

Wind

Wind typically has a lesser effect on solar power than other weather conditions. However, it can have either a positive or a negative impact in some situations. Wind can be beneficial on hotter days, as it helps keep the panels cooler, reducing the drop in production.

Wind can also cause the panels to become covered with more dirt and dust. A small amount of dirt and dust won’t lead to a significant drop in production, but you can see a fairly substantial decrease if the panels are excessively dirty and covered in a thick layer of dirt and dust.

That’s why it’s essential to have your solar panels cleaned periodically. If you live in an area that experiences fairly frequent rainfall, having a professional clean your solar panels once a year is typically sufficient. In a dry, dusty climate, having your solar panels cleaned at least twice a year will help boost year-round energy production. If weather affect solar energy production in your area through heavy dust, pollen, or seasonal debris, solar maintenance service plans can help keep output consistent.

Seasonality and how weather affect solar energy production

Even when the weather is mild, the seasons can change production because daylight hours and sun angle change throughout the year. In many northern regions, winter days are shorter and the sun sits lower in the sky, which can reduce total daily production even if the panels are working perfectly. In spring and fall, you can sometimes see strong production because temperatures are cooler while daylight is still decent, which helps panels operate efficiently. Understanding this seasonal pattern makes it easier to tell the difference between normal variation and an issue that needs troubleshooting.

Seasonality also affects shading. Trees that are not a problem in winter can create heavier shade in summer when leaves are fully out. If you see a sudden seasonal drop at the same time every year, shading is often the culprit.

Severe weather and system durability

When weather affect solar energy production, the biggest day-to-day swings usually come from changing light levels, but severe weather is where good system design really matters. Hail, heavy storms, and wind-driven debris are common concerns. Modern solar equipment is built and tested for harsh conditions, but severe weather can still cause temporary shutdowns, especially during grid outages. That is one reason storage can be valuable, because it helps you maintain power for essential loads even when the grid is down, depending on how your system is configured.

If you are ever unsure whether a production drop is weather-related or system-related, the fastest step is to verify what the system is reporting. This guide can help you tell if panels work before you assume weather is the only factor.

With over 20 years of experience, Solar Liberty is one of the leading providers of residential solar services in New York, Pennsylvania, Ohio, and Vermont. If you’re looking to go solar, we can custom-design a system that perfectly meets the energy needs of your home or business. From there, we can also handle all necessary solar installation services, maintenance and address any repairs to ensure your solar system continues to work efficiently for many years to come.

To schedule a consultation with one of our experts, contact Solar Liberty today.