How Does the Weather Affect Solar Panels & Production?

rain on a solar panel

“How does weather affect solar panels?” – From cloudy days to hail to extreme temperatures, weather has a direct effect on how solar panels perform.

We’re here to cover the frequently asked questions we hear about how weather affects solar panels, including the best temperature for solar panels and if solar panels still work when it’s cloudy.

We’ll take a detailed look at how weather affects solar energy so you can make an informed decision.

The Impact of Weather on Solar Energy

What Is the Best Temperature for Solar Panels?

True or False: The hotter the temperature, the more energy solar panels will produce.


Solar panels rely on the sun’s light, not heat, to generate energy. Solar panels convert light from the sun into electricity using photovoltaic cells. These solar cells capture light from the sun and convert it into usable AC energy by a solar inverter.

And solar panels capture and utilise light best when the panels are cooler.

All solar panels are manufactured differently and have varying efficiency based on temperature, but they all have one thing in common: the higher the temperature of the panel, the lower the efficiency.

To find out the exact impact of temperature on panels, you can check the spec sheet for results from manufacturer testing. Generally, for each degree over 25°C, the panel’s efficiency drops by 1 per cent & for every degree below 25°C, the panel’s efficiency increases by 1 per cent.

Even though hotter panels result in decreased efficiency, solar panels still generate more energy in summer than in winter. Despite being less efficient in higher temperatures, the sun is out longer every day, allowing more electricity to be produced overall.

Can I Generate Solar Power If It Isn’t Sunny?

Yes, solar panels will still generate energy even when it isn’t sunny. Of course, fog, clouds, shade, and smoke will all reduce the amount of energy your solar panels produce.

However, solar cells can still absorb light particles even on cloudy or overcast days.  A partly cloudy day for example typically only reduces production by around 10 to 25%.

An easy test to see if your solar panels are generating energy is by looking for shadows. If an object casts a shadow, there is enough light for your system to be producing energy. If no shadows are present, the cloud coverage is likely too thick to absorb light particles.

When we perform on-site evaluations for solar panel systems, we take weather patterns into account. With our extensive experience designing, installing, and maintaining solar systems throughout WA, we have a thorough understanding of local weather.

We can evaluate your location to determine how the local climate will affect your solar panel production. We’ll develop a customised setup that maximises efficiency based on local factors, including weather patterns.

We also stay up to date on all the latest advances in the industry and leading brands, so we can recommend the solar panels that will perform best based on your location and setup.

roofs in Australia with solar

How Does Different Weather Affect Your Solar?

“Will my solar panels still work in bad weather?”

This is a huge concern for our customers and we completely understand. You want the highest return on your investment and may worry about how the weather will affect your solar panel’s efficiency.

Here’s a closer look at four different weather conditions and how they each affect solar panel efficiency.

  1. Clouds – UV rays penetrate clouds, which is why it is recommended to still wear sunscreen, even on overcast days. Solar cells generate power using indirect and direct sunlight, so solar panels will still produce energy even on cloudy or overcast days. The amount of energy solar panels produce on overcast or cloudy days will depend on the efficiency of the solar cells and how dense the cloud cover is.
  2. Rain – Just like solar panels can still produce energy on cloudy days, the same is true for rain. Rain will lower your solar panel’s production, but the solar cells will still be absorbing indirect light and generating power. And, occasional rainstorms offer the bonus of a free cleaning for your solar panels if you have a sloped roof! Rain clears away dust and dirt that build up on panels, block light, and decrease production.
  3. Bushfires – Bushfires can harm solar energy output due to the accumulation of ash particles and dust on the solar panels. High smoke density can also reduce the amount of light that reaches the solar cells. In the event of a bushfire, you can wait for a good rain to wash the panels and clear away the ash and debris. Or, you can schedule a professional cleaning for your solar panels to restore them to their full production capacity.
  4. Hail – A few cloudy days or some rain aren’t a big deal for solar panels. Hail is another story. Although solar panels are tested and manufactured to hold up under extreme, harsh weather conditions, they are not indestructible. After a hailstorm, you’ll want to check your panels to ensure they have not sustained damage. If you notice damage, contact a licensed solar panel technician immediately.

When researching solar panels, check the extreme weather rating and wind load to get an understanding of the panel’s durability in harsh conditions.

cloudy sky with solar panels on roof

What Other Factors Affect Solar Energy Production?

Along with weather, many other factors affect solar energy production. One of the biggest factors that determines how efficient your solar panels are is maintenance.

Solar panels that are covered in a dusty film will produce less energy than panels that are clean and well-maintained. While the occasional rainshower is a great way to easily clean your solar panels, we recommend performing regular maintenance and cleaning to maximise your system’s efficiency and lifespan.

We recommend cleaning solar panels at least once every six months. In areas surrounded by trees or in especially dusty spots, solar panels may need to be cleaned every three months. In some cases, homeowners get away with cleaning their panels once a year.

Along with weather and maintenance, here are other factors that affect solar panel efficiency:

  • Location
  • Panel orientation
  • Roof layout
  • Panel age
  • Latitude
  • Cooling systems
  • Energy conversion efficiency
  • Installation angle
  • Inverter efficiency

At Aus Energy Solar, we have an extensive understanding of how each of these factors affect solar panel efficiency. Our solar technicians can evaluate these factors to design a solar system solution that will give you the most efficiency and highest ROI.

Is it the Right Weather to Get Solar?

The relationship between solar panels and weather is complex, but we can help you understand all the details. When you schedule a free on-site solar power consultation with us, we evaluate all the details that will affect your solar system’s output, including weather patterns. We aim to be your trusted partner in high-quality residential solar system solutions and commercial solar applications throughout WA.

Whether you’re in Sydney, Perth, or Melbourne,  get in touch with any questions or to book your free on-site consultation.