KidWind Project Solar Car, Инструкция по эксплуатации

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Solar cells are usually made of two thin pieces of silicon, the substance
that makes up sand and the second most common substance on earth.
Silicon is used because it is a semiconductor, or a solid that is in between
a conductor and an insulator of electricity. One piece of silicon has a
small amount of boron added to it, which gives it a tendency to attract
electrons. It is called the P-Layer because of its positive tendency. The
other piece of silicon has a small amount of phosphorous added to it,
giving it an excess of free electrons. This is called the N-Layer because it
has a tendency to give up negatively charged electrons. When the two
pieces of silicon are placed together, some electrons from the N-Layer
flow to the P-Layer and an electric field forms between the layers. The P-
Layer now has a negative charge and the N-Layer has a positive charge.
When the PV cell is placed in the sun, the radiant energy energizes the
free electrons. If a circuit is made connecting the layers, electrons flow
from the N-Layer through the wire to the P-Layer. The PV cell is producing
electricity—the flow of electrons. If a load such as a light bulb is placed
along the wire, the electricity will do work as it flows.
Compared to other ways of producing electricity, PV systems are expen-
sive. This is mainly because PV cells require silicon that is extremely pure.
This level of purity makes the silicon expensive. However, despite the
high cost, PV systems have many useful applications and their demand is
growing rapidly.
= protein = tightly-held electron
= can accept an electron = free electron
PHOTOVOLTAIC CELL CROSS SECTION
p-layer
n-layer
p-layer
n-layer
Nuclear
fusion
Electrons moving from
n-layer to p-layer
Photons
=
=
Solar panel cross section
Excited electrons flow through the silicon semi-
conductor from the N-Layer to the P-Layer. They
flow out the negative terminal, through the circuit,
and back to the positive terminal. When a load is
attached, the electrons are forced to do work (i.e.
light a bulb).
Solar panel