Solar energy is obtained from the sun's radiation and can be converted into useful forms of active or passive energy. Active solar energy uses equipment like solar cells to convert sunlight into electrical energy for homes, while passive solar energy uses strategic window placement for natural sunlight heating. Solar panels convert light energy to electrical current through silicon or thin-film crystals, with individual electrons becoming excited and moving freely to produce current. While solar energy has advantages like being renewable, clean and requiring little maintenance, disadvantages include high upfront costs and reliance on sunlight availability. Overall solar provides a sustainable and pollution-free alternative to non-renewable fossil fuels and carries risks of nuclear energy.

1. SOLAR ENERGY
T H E U L T I M A T E R E N E W A B L E E N E R G Y S O U R C E

2. INTRODUCTION
Solar energy is defined as energy obtained from the sun's radiation. The
two main forms of solar energy include active solar energy and passive
solar energy.
Active solar energy involves equipment or an action to convert solar
energy into a useful form. One example of active solar energy is the use
of solar cells to convert energy from the sun into electrical energy that
can be used in the home.
Passive solar energy does not require any specific action or equipment. An
example of passive solar energy is strategically placing windows in a
home to allow sunlight to enter and provide heat.

4. WORKING
Solar panel is a device that converts light energy to electrical energy.
Solar photovoltaic (PV) panels use silicon crystals, which produce an electrical current
when struck by light. While silicon is very efficient at turning light energy into
electricity, it tends to cost more than "thin film" PV panels. These thin film panels use
newer materials that produce smaller, more cost effective crystals, from materials
such as copper-indium-gallium-selenide. Thin film solar utilizes stacked
semiconductors only a few micrometers thick and has a variety of innovative
applications such as roof shingles or solar window tinting that generate electricity,
however they are usually less efficient than traditional silicon solar panels.

7. In a crystal, the bonds (between silicon atoms) are made of electrons that are shared
between all atoms of the crystal. Light gets absorbed, and individual electrons in
bonds get excited into a higher energy level and can move around more freely
than when it was bound. That electron can then move around the crystal freely,
which produces an electrical current.

8. A solar panel is a set of solar photovoltaic modulelectrically connected and
mounted on a supporting structure. A photovoltaic module is a packaged,
connected assembly of solar cells. The solar panel can be used as a
component of a larger photovoltaic system to generate and
supply electricity in commercial and residential applications. Each module is
rated by its DC output power under standard test conditions (STC), and
typically ranges from 100 to 320 watts. The efficiency of a module determines
the area of a module given the same rated output - an 8% efficient 230 watt
module will have twice the area of a 16% efficient 230 watt module. A single
solar module can produce only a limited amount of power; most installations
contain multiple modules. A photovoltaic systemtypically includes a panel or
an array of solar modules, an inverter, and sometimes
a battery and/or tracker and interconnection wiring.

10. ADVANTAGES
 Solar energy is a clean and renewable energy source.
 Once a solar panel is installed, solar energy can be produced free of charge.
 Solar energy will last forever whereas it is estimated that the world’s oil reserves will
last for 30 to 40 years.
 Solar energy causes no pollution.
 Solar cells make absolutely no noise at all. On the other hand, the giant machines
utilized for pumping oil are extremely noisy and therefore very impractical.
 Very little maintenance is needed to keep solar cells running. There are no moving
parts in a solar cell which makes it impossible to really damage them.
 In the long term, there can be a high return on investment due to the amount of free
energy a solar panel can produce, it is estimated that the average household will
see 50% of their energy coming in from solar panels.

11. DISADVANTAGES
 Solar panels can be expensive to install resulting in a time-lag of many
years for savings on energy bills to match initial investments.
 Electricity generation depends entirely on a countries exposure to
sunlight; this could be limited by a countries climate.
 Solar power stations do not match the power output of similar sized
conventional power stations; they can also be very expensive to build.
 Solar power is used to charge batteries so that solar powered devices
can be used at night. The batteries can often be large and heavy, taking
up space and needing to be replaced from time to time.

12. SOLAR-THERMAL ELECTRICITY:
POWER TOWERSGeneral idea is to collect the light from many reflectors
spread over a large area at one central point to achieve
high temperature.
Example is the 10-MW solar power plant in Barstow, CA.
 1900 heliostats, each 20 ft by 20 ft
 a central 295 ft tower
An energy storage system allows it to generate 7 MW of
electric power without sunlight.
Capital cost is greater than coal fired power plant, despite
the no cost for fuel, ash disposal, and stack emissions.
Capital costs are expected to decline as more and more
power towers are built with greater technological
advances.
One way to reduce cost is to use the waste steam from the
turbine for space heating or other industrial processes.

13. SOLAR TOWERS

14. SOLAR POWER STATION

15. HOW MUCH SOLAR ENERGY?
T H E S U R F A C E R E C E I V E S A B O U T 4 7 % O F T H E T O T A L S O L A R
E N E R G Y T H A T R E A C H E S T H E E A R T H . O N L Y T H I S A M O U N T I S
U S A B L E .

16. WHY SOLAR ENERGY?
It’s free.
Solar-energy systems allow you to capture free sunlight and convert it into usable power in your home.
It’s clean.
Solar energy can be used to heat and cool your home, but it has almost no impact on the global climate. By comparison,
electricity generated by power plants produces carbon dioxide emissions that scientists say pose serious threats to
the environment.
It’s infinitely renewable.
While nonrenewable energy sources like oil, gas and coal are becoming increasingly scarce, the sun’s energy is limitless.
Wherever sunlight shines, electricity can be generated.
It can reduce your utility costs.
Having a system that creates solar energy means you use less electricity from your utility company, and that can
contribute to lower heating and cooling costs. This is significant, especially when you consider 56% of energy use
in a typical U.S. home comes from heating and cooling.

17. FINAL THOUGHT
Argument that sun provides power only during the day is countered by the fact
that 70% of energy demand is during daytime hours. At night, traditional
methods can be used to generate the electricity.
Goal is to decrease our dependence on fossil fuels.
Currently, 75% of our electrical power is generated by coal-burning and nuclear
power plants.
Mitigates the effects of acid rain, carbon dioxide, and other impacts of burning
coal and counters risks associated with nuclear energy.
pollution free, indefinitely sustainable.

18. THANK YOU!
By,
Tanveer
Vishnu
Mamatha
Arvindh
Shruthi
Manohar