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Does solar work in winter? Winter solar panel performance explained
Does solar work in winter? Learn how solar panels perform during cold, cloudy weather in Australia and how to maximise solar efficiency in winter.
With around one in three Australian households now using rooftop solar to power their homes, many Australians may be wondering if their solar panels still work during winter and on cloudy days. Contrary to a common misconception, solar panels are indeed capable of producing energy during colder weather as they rely on light, and not heat, to operate all year round.
Find out how solar energy works during winter to help make an informed decision about renewable energy in your home.
Does solar work in winter in Australia?
Yes, solar panels still work in winter. They generate electricity from daylight, not heat, so they still produce power on cold days.
Solar panels can even perform slightly better in cooler weather, since excessive heat can reduce efficiency. But winter output is usually lower because:
- days are shorter
- the sun is lower
- cloud cover is more common
- shadows may be longer.
So solar still works in winter, but usually generates less than in summer.
How much less solar power is generated in winter?
RACV Solar spokesperson Landon Moss says winter solar output depends on panel angle, daylight hours, and weather conditions.
"Panels are still efficient in winter and can still generate energy during the winter months, although their efficiency may be reduced due to shorter days and lower sunlight angles," Moss says.
Even with lower winter output, modern solar panels can still generate useful power and help cut electricity costs during daylight hours.
"The amount of power generated by solar panels in winter can vary depending on several factors, including the specific location, weather conditions, orientation of panels, and any shading or obstructions," Moss says. "Overall, while the effectiveness of solar panels may decrease in winter, they can still contribute to energy generation for your household."
Solar panels can generate energy on cloudy days and during shorter daylight hours. Image: Matt Harvey
Do solar panels work on cloudy days?
Solar panels still work on cloudy days, but they produce less power than in direct sunlight. Cloud cover blocks some sunlight, but diffused light still lets the system generate power at a lower rate.
Modern panels are more efficient in low light, so they perform better in winter than older systems.
Does rain affect solar panels?
Rain itself does not stop solar panels from working. In many cases, rain can actually help by washing away dust, dirt and debris that may reduce panel efficiency.
During heavy storms or very dark weather, solar production will drop temporarily because less sunlight reaches the panels. Once conditions clear, the system resumes normal operation.
Solar panels installed in Australia are designed to withstand outdoor conditions including rain, wind and hail when properly installed to Australian standards.
More: How to safely clean solar panels
Do cold temperatures affect solar panels?
Solar panels are built to deal with a range of temperatures, so shouldn't abruptly stop working.
"Cold weather generally doesn't impact solar panels," says Moss. "Extreme cold temperatures can affect the panel efficiency, but they typically do not stop working altogether."
Most solar panels operate effectively in a temperature range between -30°C and 80°C, Moss says, meaning the mild winter temperatures experienced in Australia are unlikely to impact peformance.
Does a home solar battery work in winter?
A solar battery may be effective in helping to reduce your energy costs in winter. When your solar panels generate more energy than you can use, the unused energy is stored in the home battery for later use.
"Having a solar battery means excess unused energy is stored, and can be used for household consumption when the sun is not shining, such as nighttime," Moss explains. "This benefits the household by not having the need to buy power from the grid at a higher rate."
Moss recommends batteries from a certified solar provider so you can generate, store and manage your own energy. Batteries with a back-up function also allow the power to run during a blackout.
More: Solar panel & battery rebates Victoria 2026
Does it take longer to charge an EV during winter using solar power?
The electrolytes in EV batteries perform better in warmer temperatures. This means that during winter, EVs can take longer to charge.
While your EV can still be charged using solar power during winter, running multiple appliances concurrently during winter may mean you also need to draw additional power from the grid.
Measures like preheating EV batteries before charging, charging your EV during peak daylight hours (generally 10am to 2pm in winter) and installing a solar battery may help mitigate the need to import energy from the grid.
Do solar hot water systems work in winter?
Solar hot water systems also continue working during winter, although they may rely more heavily on booster systems during colder or cloudy periods.
Most solar hot water systems include either electric boosters or gas boosters. These help ensure households still have reliable hot water when solar heating alone is insufficient.
Well-maintained systems with properly insulated tanks generally perform effectively throughout winter. Heat pump hot water systems are another good option for this reason.
EVs can take longer to charge in winter. Image: Matt Harvey
Can solar power save money in winter?
Yes - although winter solar generation is lower, solar panels can still reduce electricity bills. Many households use more electricity during winter because of:
- heating systems
- hot water usage
- clothes dryers
- increased use of home appliances.
If your solar system generates electricity during the day while these appliances are running, you may reduce the amount of power you need to buy from the grid.
Adding a battery storage system may also help households use more of their solar energy during winter evenings when electricity demand is typically highest.
How to improve solar performance in winter
While you cannot control daylight hours or weather, there are several ways to maximise solar efficiency during winter.
- Keep solar panels clean - dust, leaves, bird droppings and grime can reduce solar performance. Winter rain often helps clean panels naturally, but it may still be worth checking for build-up or debris after storms or high winds. Solar panel cleaning is recommended at least once a year.
- Trim nearby trees - the lower winter sun can create longer shadows from trees, chimneys or neighbouring buildings. Even partial shading on a solar panel can reduce overall system performance. Trimming overhanging branches may help improve sunlight exposure during winter.
- Monitor your system performance - most modern solar systems include monitoring apps or online portals that show how much electricity your system is generating. A noticeable decline in generation may indicate the system needs inspection or maintenance.
- Use appliances during daylight hours - running high-energy appliances like dishwashers, washing machines, heating systems and EV chargers during the day can help you use more of your solar-generated electricity directly.
- Consider battery storage - solar batteries store excess solar energy generated during the day for use later at night or during peak demand periods. During winter, battery systems may help households use more self-generated energy to reduce evening electricity costs.
Is winter a bad time to install solar?
Winter can actually be a good time to install solar panels.
Installing solar before peak summer sunlight allows households to start generating renewable energy sooner and potentially reduce energy bills year-round. Solar installers may also have shorter wait times outside peak demand periods.
