Transcript The forms for Solar energy - Pedagogisk Inspiration Malm&#246

What is solar energy?
“The sun is a very
powerful source of
energy. Without the
sun's heat and light,
human life on earth
would not be
possible.”
What do we use solar power for?
“All aspects of our daily life
involve the use of energy: we
use energy for transport, for
production of food and
water(pumping) and for
heating or cooling our homes
and offices. Fossil fuels such
as oil, coal and natural gas
are used most despite the fact
that the amount of solar
energy that reaches the earth
in one day is more than
sufficient to satisfy the worlds
yearly energy demand.”
How Does We applie solar
Power?
“Solar energy can be applied in
many ways. Apart from simple
forms of solar energy to dry
clothes , heat water or buildings
or dry agricultural produce , we
can also use the power from the
sun to produce electrcity for
households offices . Besides
these direct forms of solar
energy, also hydropower, wind
and wave power originate from
the energy of the sun and are in
fact indirect forms of solar
energy.”
What we can use with Solar Electricity
• The energy from the sun
can serve many purposes.
One of them is to generate
electricity.
This is what we call solar
electricity. Using solar
panels, the sunlight is
directly converted into
electricity. This process is
called the photovoltaic
effect
The Photovoltaic effect
• For solar electricity you need a solar panel that consists
of one or more solar cells. When sunlight falls onto a
solar cell, the solar cell material absorbs some of the
light particles. Each photon contains a small amount of
energy. When a photon is absorbed it starts a process of
freeing an electron in the material of the solar cell.
Because both sides of a solar cell are electrically
connected with a wire, a current will flow when the
photon is absorbed. The solar cell now produces
electricity, which can be used instantly or stored in a
battery.
Solar electricity
• Solar electricity can be used in three basic forms:
Stand-alone No electricity grid is available or a connection to the grid is not
made. Solar panels produce electricity for lighting, TV and radio, water
pumping, a refrigerator or tools. Normally, electricity storage is provided by
batteries to secure energy supply at night and other times when the solar panels
don't produce electricity.
• Grid-connected In areas where an electricity grid is available, solar
panels can be used to produce your own clean electricity by using
daylight and roof space
Back-up The system is connected to an electricity grid of poor
quality. In case of blackouts solar electricity cover the electricity
demand.
The principe of Solar electricity
• 1.
light (photons)4.
diversion layer
• 2.
front contact 5.
positive layer
• 3.
negative layer 6.
back
contact
What is Solar Heat?
The energy of the sun can serve
many purposes. One of them is
to generate heat. This is what we
call solar heat. Using solar
collectors the sunlight is directly
converted into heat.
The use of solar heat has many
advantages. It is a clean, quiet
and reliable energy source.
Solar heating systems have
been used since the 19th
century. Nowadays the use of
solar heat is widespread.
World wide about seven
million households presently
use Solar Hot Water Systems.
In households connected to a public energy grid (electricity, gas) the
use of a Solar Hot Water system can save 50% or more on the
energy bill for domestic hot water preparation.
In remote areas
without a
connection to a
public energy
grid, solar
energy is used
for heating
water for
households and
hospitals or for
drying
agricultural
products.