Solar Panels in Winter and Rain

Solar Panels in Winter: Performance 

If you live in California, you already know that the Golden state is a great place for solar power! There is plenty of sunshine and taxpayers can claim a 30% federal tax credit off the cost of a solar PV system.

However, California winters have become unpredictable in the last couple of years, when it comes to weather. One day the sun is shining, the next there is a full-on downpour. These frequent rain showers make solar homeowners wonder if solar panels will still generate power when the sky is gray. Which requires some knowledge of solar panels in winter and rain.

Solar PV System Efficiency and Rain

The good news is your solar PV system will still produce energy even when it’s raining and cloudy outside. Solar panels installed on your roof can use direct or indirect sunlight, though they are most effective when they receive direct sunlight. On cloudy or rainy days, photovoltaic panels can produce anywhere between 10-25% of their optimal capacity. The exact amount will vary depending on how dark and heavy the rain and cloud coverage is overhead. It is interesting to note that rain does help your solar panels operate more efficiently after the storm because the water washes away any dirt, dust, or pollen.

SunPower Solar Panels 

The type of solar panels installed on your roof also affects how much power they produce during overcast or inclement weather. Del Sol Energy uses SunPower solar panels, which are designed to capture a broader range of the solar spectrum. The SunPower photovoltaic panels deliver some of the highest efficiency numbers available in the solar industry so there is no question that your solar power system will generate electricity even when it’s overcast or raining.

California also has 3 major utilities (PG&E, SCE, and SDG&E) with strong net metering policies. This means energy produced by your solar system when the sun is out and shining will offset the power used when your system is not operating at full capacity such as during a rainstorm or at night. Think of it like rollover minutes on a cell phone, or like using your utility company as a “virtual battery.”

If you have any other questions about solar panel efficiency during rainy, cloudy days, please give us a call! Del Sol Energy is happy to answer all your solar energy questions! We will walk you step by step through the process of going solar! We install solar power systems across California including Brentwood and Discovery Bay. Schedule an in-home consultation with our experienced solar specialists today!