It can be an interesting dilemma for those who are looking to reduce global warming when they stop to consider the dark color of solar panels. After all, haven’t we been told that it’s the bright white quality of polar snow that reflects sunlight (and its’ heat) back into space?
And if this is true, then wouldn’t the darker color of solar panels do the exact opposite – absorb light, and thereby retain unwanted heat?
The undeniable truth about solar panels is that the embedded solar cells must absorb light in order to excite electrons; a process that is then harnessed to produce power.
If solar cells were reflective in color, rather than the dark color that they are, then sunlight would not be absorbed and consequently, electron excitation would only occur at a significantly reduced rate – greatly diminishing power output.
Knowing this, are we to conclude that the light absorbing characteristic of solar panels is actually contributing to global warming?
Solar Panels; The Greenhouse Vs. A Match
One of the issues with hearing terminology repeated over and over again is that we often associate the end idea without remembering to embrace the original meaning. I believe this is the case with the phrase, ‘greenhouse gases’.
To understand why these gases in the atmosphere are referred to as ‘greenhouse gases’ we must establish why the term greenhouse was adopted rather than just referring to them as detrimental gases.
The makeup of a greenhouse is fairly simple, composing of a support structure and a clear plastic type covering. This plastic is the most crucial component of a greenhouse as it allows sunlight in, while prohibiting the heat to leave – generally by means of restricting airflow.
While incredibly simple, this design can see interior temperatures well above freezing while the outside environment is covered with snow. And this is accomplished without any major insulation or, often, even supplemental heat.
With this understood, we can now make the association between the plastic covering of a greenhouse and the detrimental gases that allow sunlight in while prohibiting heat to leave.
So how do solar panels play into this?
As seen in the article, ‘Do Solar Panels Get Hot?’ the heat generated by a solar array can be notable. If this is true, then wouldn’t solar panels actually contribute to global warming?
The answer to this lies in the scale of things.
If you were to put all of the solar panels in the world into one massive array, then their size would be somewhat comparable to a single match laying on the floor of a professional greenhouse.
To any fingers in the immediate area of the match, things would be quite hot. But the impact of heat generated by the match would be negligible considering the enormous volume of space inside of the greenhouse.
From this example, we can understand that while solar panels do in fact absorb light, and generate heat as a consequence, any contribution to global warming would be very difficult to measure.
Conclusion
The real contributor to rising temperatures around the globe, is the inability of our planet to shed the heat that it normally used to.
So while solar panels do, in fact, generate heat, any temperature increase will largely go unnoticed when put on a global scale. However, their impact on the planet can be most notable as they are able to generate power without producing the ‘greenhouse gases’ that essentially form the heat trapping film that covers our planet.
This is a stark contrast to the power produced by the burning of coal or gas.