Here’s a question asked by analytical minds: “Do a solar panels work (generate power) from the sun’s light, or from its heat?” The question can be simply answered. But for the sake of satisfying your analytical mind, let’s look at this subject a bit more in-depth.
We all know that solar energy comes from the sun. But which element of the sun is responsible for the eventual energy we derive from this resource? The sun is a limitless source of energy—both in terms of light and in heat. So can we only utilize one of these elements or both?
Is there a difference between sunlight and the sun’s heat?
The sun is synonymous with heat creation. But it’s also how we know it’s day time, because of all the light it creates. When we speak of the sun’s light and the sun’s heat, we are obviously talking about two different things.
But in terms of solar energy, these two are more similar than you may realize. Both light and heat are an electromagnetic type of energy. The technical answer to our main question is “Light.” But the light that penetrates a solar panel is actually excited to a point of kinetic energy.
The same LIGHT photons that create this energy on a solar panel create HEAT on other surfaces. For instance, if you have a solar-heated pool, the same sun that creates light on a solar panel will here create heat on the water pipes. So while we may see them as completely different aspects of the sun, the energy type is virtually the same.
What happens when light penetrates solar panels
So now that we know that it is light which creates energy in a conventional solar panel, let’s see how this process works. To put it simply, light photons are already a form of energy. When they hit solar panel cells, they create a new type of energy called kinetic energy.
This kinetic energy is constantly in motion. That motion is what pushes the newly created energy out of the panel cells and out to the rest of the system. The system will then—through several processes—create the energy we use in our homes.
How to intensify the efficiency of a solar panel by exploiting light
Now, because light is the determining factor in solar power creation, many people have created ingenious methods of harvesting that light more effectively. The most popular way of doing this to date is through the use of mirrors.
If a number of mirrors can concentrate the light into one area, what you have is essentially multiple suns shining onto one panel. On a panel that has an efficiency rating of 20%, this can almost double the efficiency.
Another method of increasing efficiency is by creating panels that move with the sun. It goes without saying that at the time the sun shines directly at the panel, it has the highest efficiency. If, however, the panel moves with the sun, it gets direct exposure all day long; instead of for just an hour or two.
Can the sun’s heat also be used to generate electricity?
There are also solar panels that use the heat of the sun to generate power. Thermoelectric materials are used to manufacture solar panel cells so that the heat of the sun is converted and stored.
The problem with this method is that of efficiency. The sun creates light whenever it is up—even if it’s concealed behind clouds. But the sun—even when it’s up—doesn’t always create heat. For this reason, light solar panels are way more popular in most countries.
That being said, there is also solar panel technology that makes use of both these methods. This of course generates more electricity than either of the two that only use one of these methods. However, these panels cost way too much to manufacture and most users are simply not willing to pay the price for this efficiency.
Do solar panels work on light or heat?
So for the most part, light solar panels are used to power a home or business. Chances are, if you see a solar panel up on a roof somewhere, that solar panel is making use of the sun’s light rather than its heat.
Bear in mind that the two are similar in their energy form. For this reason, we can make use of both aspects to generate higher efficiency. Hopefully, in the near future, this technology will be more affordable than it is now.
* Next generation solar panels: YouTube video