2019 Do Solar Lights Work in Winter?
The short answer is Yes. Solar Powered Street Lights do work in the winter. In fact, solar PV panels work better in cold temperatures than in hot temperatures (which we will explain later why).
If you are wondering how well they work during cold seasons, we’re here to answer that. In this article, we’re going to unravel your unsolved myths and questions about solar lights installed in cold climate countries. Read on!
Do Solar Lights Work in Cold Weather?
PV panels work by absorbing direct sunlight. It doesn’t matter if you’re experiencing cold or hot ambient temperature, as long as UV rays hit the PV panels.
To picture this, let’s first demonstrate how PV cells work through the Photovoltaic Effect.
When the rays hit the panel, the electrons within it will be disturbed by the incoming photons from the sun. Because the electrons are displaced from immobility, they will now be in motion. The electrons will now flow into a stream of electrical current.
There’s no heat involved in the process so when generating electricity, you don’t necessarily need a warm climate. You just need enough sunlight to directly hit your solar panels for 6 to 8 hours before it gets fully charged. This can be used for 4 to 7 days autonomy.
So to answer that question: Yes, solar street lighting system can work in cold weather.
Do Solar Panels Work Better in Cold Climates?
Solar panels in solar street lights can not only work great during winter, but they generate electricity better.
For one, winter snow is white and reflective. In fact, snow is the most reflective natural blanket of Earth. And thus, this renders solar panels free sunlight projection services.
This means that snow acts as a mirror projecting sun rays toward the solar panels for better PV performance. This not only intensifies the rays that hit the solar panel, but also allows more UV rays to be harnessed.
Another thing is that the cooler temperature can also help improve the output of the PV panel. Many people’s common notion is when it’s cold, the solar panel cannot optimize conversion. This is wrong. Photovoltaic cells can actually function better in colder climates than hot climates.
How Does Temperature Relate to How PV Cells in Solar Lights Work?
You might be wondering how solar PV cells work more efficiently in cold weather.
As mentioned earlier, solar panels work with electrons bumping and moving within it. When the system experiences cold temperature, the electrons won’t budge that much.
So when sunlight hits the panel during cold weather, there’s no excessive electron movements. This will naturally incur a huge voltage difference. And with a big voltage difference comes more energy produced.
In contrast, when the temperature is extremely hot, such as in deserts, the electrons have more input activity than the output energy. This is because excessive heat can lower the electron’s efficiency in converting the sun’s energy to current. In fact, solar panel efficiency may decrease above 77 °Fahrenheit (25 °Celsius).
And you know how excessive input versus a smaller output can lower a system’s efficiency, right? As a result, hot temperatures can actually lower your energy production. So the best scenario for solar lights is when the temperature is cold and there’s still a gleam of sunshine.
That also explains why one of the most efficient solar light systems in North America is in Canada, during its cold, sunny days.
But don’t conclude here just yet. There are reasons why some naysayers don’t agree with solar street light installations in winter. The next chapter explains why.
Can Solar Panels Withstand Snow?
Um…it depends. Because if it’s snow covering the face of your solar panel, it’s another story.
When snow accumulates on the surface, it can block the sun’s rays from reaching your panels. Thus, there will be a decrease in electricity produced.
That’s why manufacturers recommend installing PV panels in a tilted manner so that it would get off any particles and snow for an optimized energy conversion.
The great thing about solar panels is its sleek design. You see, they are designed with a smooth and tempered glass finish so as not to magnetize or attract any matter. When snow does accumulate on top, its sheeny surface can easily slide off the snow when it melts a little.
But don’t get us wrong. A pile of snow can reduce energy production. If a blizzard hits your town, snow can heavily accumulate on the panel’s surface, making it harder for it to receive sunlight.
In fact, a study reveals that solar panel production can be reduced by 0.85% to 5.31% when snow entirely covers the surface like shown in the picture.
Of course the most logical thing to do is to clean it. But be careful not to damage the glass with your snow rake.
Sometimes, hosing it down can do the trick of getting rid of snow. But if you can’t do the cleaning alone, better call the people offering solar panel cleaning.