1. DOES TEMPERATURE AFFECT THE AMOUNT OF
ENERGY A SOLAR PANEL PRODUCES?
By Frank Scotti
July 1, 2013
Temperature doesn't really affect the amount of solar energy a solar panel receives. It does, however, affect
how much power you will get out of it. Here’s why. As the solar panels get hotter, they will produce less
power from the same amount of sunlight (photons). Normally, electrons at rest (low energy) are excited by
sunlight (high energy), and the difference between their excited and rest energies is the potential difference
(voltage) that you get from your solar panel, the amount of energy. However, heat also excites electrons
(when we heat something we are giving it energy), which raises the energy of the electrons at rest.
("warmer" electrons have more energy at rest than their "cold" counterparts.)
The most power from solar panels is produced when the electrons are at their greatest stage of rest and are
exposed to the greatest amount of sunlight, giving us the greatest difference between the two stages. When
your solar panels are hotter, the electrons are already at a higher level of excitement. Thus the difference
between the rest energy and excited energy (from the sun) is smaller, and our solar panels will produce less
energy. Panels must reach temperatures exceeding 120° for a drop in energy generation to start to occur.
And even then, it is minor.
Here’s my analogy. A can of unopened
soda has a certain amount of
carbonation energy that is released
when I open the can. Most of the
carbonation energy remains in the liquid.
If I shake the can, adding energy, and
then open it, less of the carbonation
energy remains in the liquid. Cooler solar
panels are like unshaken soda cans. Hot
solar panels are the shaken can of soda.
Temperature minimally affects the
amount of energy a solar panel
produces.
1.
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