solar panels on the roof

Do solar panels work on cloudy days?

Rod Johnson Solar

It’s been said time and again: solar energy is the most abundant energy on earth. And experts believe that harnessing solar energy will play a key role in solving the world’s energy problems.

One of the best ways to capture solar energy is through a system of solar panels.

Solar panels collect a tiny fraction of the 173,000 terawatts of solar energy that the sun continuously delivers. That’s about 10,000 times more than the total energy consumption of the world!

But the problem is, the sun doesn’t shine 24 hours a day.

So what happens then? Do solar panels work on cloudy days? Do solar panels work when it’s raining?

Solar panels on a cloudy or rainy day

Solar panels are at their best when they are being struck by a good amount of sunlight on a bright, sunshiny day. But that doesn’t mean that they will not work on overcast days.

Though much less compared to a sunny day, solar panels will still be efficient in terms of capturing solar energy even if they are blocked by clouds or during rainy days.

The efficiency of solar panels will be based on solar irradiance or the measure of how the sunbeams hits the earth’s surface – or the solar panels in this case.

The higher the solar irradiance, the more electricity that the solar panels can generate.

But the good news is that solar irradiance has a fluctuation rate of only around 6% per year. Despite this, the amount of energy that solar panels will receive will still remain constant in a given year.

Sun’s still out on cloudy or rainy days. A diffused form of it, actually.

Diffused sunlight or diffused radiation is when the sunlight travels down in a scattered or diffused form instead of a straight path.

Additional factors

However, the percentage of the solar panels’ effectiveness will still depend on the degree of cloud cover, the duration and intensity of rainfall, and the type of solar panels that will be used.

Due to their ability to absorb a wider range of light, amorphous solar panels are the most effective type of solar panel when it comes to generating power during cloudy days.

One of its drawbacks is its solar panel efficiency rating. At around 6%, amorphous solar panels are less efficient in converting solar energy to electricity.

Its longer-lasting and more solar cell efficient counterpart, crystalline-based solar panels, has the capability needed to harness solar power even if the sun is hiding behind a thick section of clouds as well.

Overcoming the cloudy or rainy day dilemma

Cloudy or ray day worries can be conquered by properly storing solar energy. This can be done by having a battery storage system or a battery bank.

The system will store the energy that will be collected on days when solar irradiance is higher. Some even prefer to have a backup system that can be turned on if there isn’t enough sunlight being captured for a specific purpose.

Keep in mind that the total amount of solar energy that will be harnessed per year is what counts. A few cloudy or rainy days will barely matter.