Will Solar Panels Produce Energy When It’s Cloudy? What About a Blackout?

Some might think that solar panels are the ultimate power hack, especially for those of us who live in the “Sunshine State,” right? But people who actually live here know what comes with also being the lightning capital of the US (and all the severe weather that earns us that title).

Severe, often cloudy weather. Weather that may cast a shadow of doubt over just how effective solar energy really is in Florida.

Our notoriously unforgiving weather (among other things) has also put us at the top of the list of states with the worst electrical blackouts in the nation. Therefore, some pertinent questions might be, “do solar panels work on cloudy days?” and “do solar panels work during blackouts?”

Keep reading. The answers might surprise you!

How Do Solar Panels Work?

A solar panel is a large array of solar cells (also called “photovoltaic cells”), which are mostly made by layering semiconductors like silicon doped with boron and phosphorous. When light particles (photons) from the Sun strike one of these cells, the electrons (or other charge-carrying particles) in it become excited enough to achieve a higher energy state.

The resulting separation of charges produces an electric potential (voltage), and electric current flows through the material in the solar cell to cancel this potential. This flow of electricity from the solar panel occurs at usable levels via direct current (DC).

Finally, an inverter converts this into alternating current (AC) so that you can use it in your home or office. 

Do Solar Panels Work on Cloudy Days?

A common reason that folks who oppose solar power (yes, they do exist) cite for their dislike of it is that it’s weather-dependent. Some even go as far as saying that solar panels don’t work at all in cloudy weather!

Well, that claim is patently false. As you learned above, solar panels work by absorbing photons. They’re designed to absorb mostly photons with wavelengths in the visible spectrum. Mostly. Solar panels can still make use of light that is slightly above and below the visible spectrum.

And although clouds may block a lot of sunlight, they don’t block all of it–certainly not all of those parts of the EM spectrum outside the visible range that the solar panels can still use.

That being said, the short answer is yes. Solar panels do work in cloudy weather. Their power output may fall to between 10 and 25% of clear-sky performance, but they do still work!

The Edge-of-Cloud Effect

Paradoxically, cloudy conditions may actually increase your solar panels’ power output, at least for a short time. This is due to a phenomenon called the “edge-of-cloud effect.”

Basically, as the Sun begins to pass behind, or emerge from, cloud cover, the cloud’s vaporous body can momentarily reflect and/or refract the incoming light rays. This focuses more light onto the photovoltaic cells and intensifies the light already striking them. And that increased input, of course, leads to increased output.

But because such a surge in power can blow fuses and decrease the lifespan of an inverter, measures need to be taken against mishaps.

Do Solar Panels Work During Blackouts?

The answer to this is yes! And no. It depends.

The fact is, your system is probably tied to the energy grid. Normally, your grid-tied system will generate the free, clean energy you got solar panels for in the first place. Thus, as long as they’re generating electricity, you’ll usually have access to it.

Usually. One disadvantage of running on a grid-tied system is that it has to obey the rules of the utility. Therefore, when the grid goes down, you won’t have access to electricity no matter how much of the stuff your solar panels are generating.

So, it looks like even though your solar panels will technically be “working” during a blackout, they won’t be doing you any good if your system is tied to the grid.

However, there are two noteworthy exceptions to this. One is that your solar system is able to store power in batteries (insert “batteries not included” joke here). The other is that you take your solar system off the grid altogether.

Now, being connected to the electric grid does have its perks. First of all, you’ll be allowed access to power even when your solar system isn’t generating enough (e.g., during especially cloudy weather or at night). Also, you can send any excess energy back to the grid for credit. This is called “credit metering” and has been available in Florida since 2008.

Taking yourself off the power grid means forgoing the above benefits. It means you’ll only have access to what your own solar system can generate and store in batteries (and any backup electricity you can generate on-site). But when—not if—the grid goes down, you’ll still have access to that same power supply!

Backup Generator

Now, in the event that your grid-tied solar system does fail (and in Florida, it inevitably will), you’ll be glad to have a generator backup, especially during those long periods without power we’ve all experienced in the aftermath of the many hurricanes and tropical storms that get aimed at us.

How Can I Go Solar?

Well, do solar panels work on cloudy days? By now, you know that the answer to that question is a clear and resounding “yes!”

And armed with the knowledge that if you embrace solar energy, you can keep your air conditioning running even during a blackout, you may now be wondering how you can go solar.

If you’re in the Tampa area, then look no further than West Bay Energy! Our dedicated team of experienced professionals can have you running on sunshine in no time.

Just give us a call at 727-758-4749 if you have any questions. Or, if you’d like to request a quote, just click here and fill out a quick form.