Fronius IG 15 - Manual (Page 15)

7
ENEN
The energy from worldwide insolation amounts to a total of about
1,540,000,000,000,000,000 kWh/year (1,540 Peta kWh/year). This is
15.000 times as much as the electricity consumption worldwide. We
congratulate you on your decision to actively use world’s biggest energy
pool. By the way, it was a scientist in the field of of physics, Alexandre-
Edmond Bequerel, who first discovered the photo-voltaic effect in 1839.
The name photo-voltaic comes from the driving force behind this techno-
logy, which is the ray of light. The ray of light consists of unimaginably tiny
particles, the photons. General infor-
mation
How a photovoltaic system works
Let us simply start our explanation with a straight silicon solar cell. Re-
membering our physics class in school, we know that there are four elec-
trons in the outside electron shell of a silicon atom arranged around its
atomic nucleus, they are the so-called peripheral valency electrons. The
sunlight’s photons enter the solar cells and concentrate energy in the
valency electrons. The electron eventually separates from the silicon atom
and leaves behind it an atom with a positive charge.
So that the free electrons will flow in one direction and thus generate
electricity, the poles on the front and back side of the cell must be diffe-
rent from each other.
The silicon atoms of the front must be packed with a slight quantity of
phosphor atoms which contain an additional valency electron. On the
back of the cell, atoms of boron having only three valency electrons are
added to the silicon atoms.
The result is an imbalance which makes the electrons flow, and this is
how electric power is generated.
Many such solar cells united together and packed behind glass form one
of your solar modules.
Your roof is
your power
generator
General Introduction