The document discusses solar energy and its uses. It notes that the sun is a continuous source of renewable energy that powers life on Earth. Solar energy is transmitted via radiation and can be harnessed using solar cells, which convert sunlight into usable electrical energy. The key components of a solar cell are the photovoltaic effect in silicon semiconductors that generate electricity when struck by photons. Connecting multiple solar cells together in an array increases the voltage output to usable levels. Solar energy systems have significant advantages as they produce no pollution or greenhouse gases.

1. A Brief on solar energy and its uses……

2. Sun is a continuous source of energy.
The energy produced by the sun is
renewable type and is unending.
It is the reason why there is survival of
the entire universe.

3. The constant and continuous energy released by the
sun is known as solar energy. The energy is transmitted
by a process known as RADIATION. Out of all the energy
that is being concentrated on the Earth only a 70% is
being received by the Earth due to its albedo.

4. Advantages and Disadvantages
• Advantages
• All chemical and radioactive polluting byproducts of
the thermonuclear reactions remain behind on the
sun, while only pure radiant energy reaches the Earth.
• Energy reaching the earth is incredible. By one
calculation, 30 days of sunshine striking the Earth
have the energy equivalent of the total of all the
planet’s fossil fuels, both used and unused!
• Disadvantages
• Sun does not shine consistently.
• Solar energy is a diffuse source. To harness it, we
must concentrate it into an amount and form that we
can use, such as heat and electricity.
• Addressed by approaching the problem through:
1) collection, 2) conversion, 3) storage.

5. Using a device known as solar cell the solar
energy is being converted to usable electrical
energy that is DC in nature.

6. What is a Solar Cell ?
A solar cell is a semiconductor device which converts
electromagnetic radiation into electrical signals.
It is a device which generates electricity directly from Sun’s
radiation by means of the photovoltaic effect so it is also called
Photovoltaic cell.

In order to generate useful power, it is necessary to connect a
number of cells together to form a solar panel, also known as a
photovoltaic module.
The nominal output voltage of a solar panel is usually 12
Volts, and they may be used singly or wired together into an array.

The number and size required is determined by the available
light and the amount of energy required.

7. The Photoelectric Effect
• The photoelectric effect relies on the
principle that whenever light strikes
the surface of certain metals electrons
are released.
• In the p-n junction the n-type wafer
treated with phosphorus has extra
electrons which flow into the holes in
the p-type layer that has been treated
with boron.
• Connected by an external circuit
electrons flow from the n-side to
create electricity and end up in the p-
side.

8. Working of solar cells
WWKJRHKJHWKJEHREWLRKJWERJcted to the solar cell , electrons
flow in the circuit and the current is generated.
When the solar cell is placed in the influence of heat energy an
electron hole pair is being created by the p-type and n-type
semiconductors.And thus the current is generated and is used
By the respective device as per requirement and efficiency.

9. Different Types of Solar
Cells
Amorphous Solar Cell
Crystalline Solar Cell

10. Types of Crystalline Solar Cells
Single Crystal Solar cells
Polycrystalline Solar Cells
Multicrystaline solar cell
Monocrystaline solar cell

11. Efficiency of Solar Cell
• Efficiency of a Solar cell is the ratio of the electrical power
output to the light input.
• The Efficiency can be increased by using an anti-reflection
coating on the thin heavily doped surface.
• The maximum efficiency so far is 18.7%.

12. How Does A Cell Become A Module?
• A solar cell is the basic building block
of a PV system.
• A typical cell produces .5 to 1V of
electricity.
• Solar cells are combined together to
become modules or if large enough,
known as an array.
• A structure to point the modules
towards the sun is necessary, as well
as electricity converters, which
convert DC power to AC.
• All of these components allow the
system to power a water pump,
appliances, commercial sites, or even
a whole community.

14. Solar car
Solar heater Solar lights
Applications
Solar cars
Solar water heaters Street lights

15. Pros and Cons of electricity
production
• PV can be designed for a variety of
applications
• No noise or air pollution
• Require minimal maintenance and have long
service life times.
• Power can be either centralized in individual
homes or distributed by electrical companies.

16. Photovoltaic (PV) systems—have very little
impact on the environment, making them
one of the cleanest power-generating
technologies available .
Solar power produces no air pollution.
•Solar power produces no greenhouse gases,
so it does not contribute to global warming.
Pros and Cons of electricity production
Contd…

17. Life
• Average 20-30 years
• Efficiency decrease 1% a year.
• Research on manufacturing and output
efficiency and recycling ongoing.
• Payback or energy break even - 15 years.