KidWind Project Solar Car, Инструкция по эксплуатации

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What is Solar energy? How does it work?
Every day, the sun sends out an enormous amount of energy. It radiates
more energy in one second than the world has used since time began!
This radiant energy, also known as solar energy, is vital to us because it
provides the world directly—or indirectly—with almost all of its energy.
In addition to providing the energy that sustains the world, solar energy
is stored in fossil fuels and biomass, and is responsible for powering the
water cycle and producing wind!
Solar energy comes from within the sun itself. Like other stars, the sun is a
big ball of gases, mostly hydrogen and helium. The hydrogen atoms in
the sun's core combine to form helium and radiant energy in a process
called
nuclear fusion . This process creates a large amount of radiant
energy, which is emitted into space. Only a small portion of the energy
radiated by the sun into space strikes the earth, one part in two billion.
Yet this amount of energy is enormous. Every day, enough energy strikes
the United States to supply the nation's energy needs for one and a half
years!
Solar energy is considered a renewable energy source. Renewable
sources of energy are resources that are continually renewed by nature,
and hence will never run out. Solar power is considered renewable
because the nuclear (fusion) reactions that power the sun are expected to
keep generating sunlight for many billions of years to come.
Solar Electricity and Photovoltaic Systems
Solar energy can also be used to make electricity. This is done largely
through the use of photovoltaic (or PV) systems. Photovoltaic comes from
the words photo, meaning light, and volt, a measurement of electricity.
Photovoltaic cells are often called solar cells. They convert light directly
into electricity.
The photovoltaic effect is the basic physical process through which a PV
cell converts sunlight directly into electricity. PV technology works any time
the sun is shining, but more electricity is produced when the light is more
intense and when it is striking the PV modules directly when the rays of
sunlight are perpendicular to the PV modules.
Sunlight is composed of photons, or bundles of radiant energy. When
photons strike a PV cell, they may be reflected or absorbed, or transmit-
ted through the cell. Only the absorbed photons generate electricity.
When the photons are absorbed, the energy of the photons is transferred
to electrons in the atoms of the solar cell.
With their newfound energy, the electrons are able to escape from their
normal positions associated with their atoms to become part of the cur-
rent in an electrical circuit. By leaving their positions, the electrons cause
holes to form in the atomic structure of the cell into which other electrons
can move.
The Greenhouse Effect
Nuclear Fusion
Heat
Atmosphere
Heat
Sun
Earth
Solar energy rays
He
H H
H H
Energy
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