Document 7279752

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Transcript Document 7279752

How Do Solar Cells Work

Aaron Culler

•Solar cells Power houses, Calculators, Intro and NASA space crafts •Solar revolution Every one gets free energy • Sun Shines 1000 watts of energy per square meter

PV Cells • PV Cells stand for Photovoltaic •Photo=Light Voltaic=Energy

PV Cell • Made of Silicon • Absorbed photons let electrons flow freely which make electrical current = electricity • Current with cells voltage = Power

• PV cells have more electrical fields •These currents are used to power calculators, houses, and etc.

PV Cells

PV Cells • The fields force freed light to flow in a certain direction to make a current •This current can be drawn off to be used externally.

Silicon In Solar Cells

• Special properties in crystalline form.

• Atom has 14 electrons in three different shells.

•First shell closest to the center is full •Outer shell half full with 4 electrons.

•Silicon atoms try to fill up the last shell

Technology •coating, N type semiconductor, P type Semiconductor, and then Black Contact •Solar Cells very complicated •Top of Solar cell is glass cover next is Transparent adhesive,anti Reflection

Technology • Process of adding impurities to a Solar cells is called doping.

• Silicon + Phosphorous = N Type • Boron is added to N type silicon for better conductor •Result of adding boron is P type cell •P type Positive •N type Negative

Technology • Silicon has 4 shells in the outer shell and phosphorous has 5 in the outer shell so these two atoms can bond their electrons. When bonded there is one electron free. Free Electrons are called free carriers and can carry an electrical current.

Technology • This process creates an electrical current.

• When light is absorbed into the solar cell the electrons are knocked loss the try to find a hole on the P type side.

About Me Hi my name is Aaron Culler. I live in Winston Salem and in my free time I like to draw and play basketball.