1. Alternative sources of energy-
renewable energy
By
San wan

2. Why do we need alternative fuels ?
Our present fuel resources are not going to be around forever
and with the ever increasing consumption their extinction is
nearly unavoidable. Also our fuel resources which are mostly
made up of fossil fuels are not renewable in nature
Currently around the world the consumption of fossil fuels is
100,000 times faster than their natural production
Another fact which should also be paid attention to here is
that the consumption of fossil fuels is eating up our
environment very fast. This causes global warming that melts
the polar ice caps and affects weather all around the world

3.  Alternative sources
• Solar energy
• Wind energy
• Geothermal energy
• Tidal energy

4.  Solar energy
• Solar Energy is the energy received from the sun that sustains life on earth.
For many decades solar energy has been considered as a huge source of
energy and also an economical source of energy because it is freely
available. However, it is only now after years of research that technology as
made it possible to harness solar energy
• India gets more than 5,000 trillion kWh of Solar Energy every year. This
much of energy is very high compared to the overall energy requirement
and consumption in the country. As regards the latest trends in developed
countries like the U.S. and Japan, it is estimated by industry experts that
millions of homes around the world are going to switch to solar energy in
the next few years.

5.  Wind energy
• The terms "wind energy" or "wind power" describe the process by
which the wind is used to generate mechanical power or electricity.
Wind turbines convert the kinetic energy in the wind into
mechanical power. This mechanical power can be used for specific
tasks (such as grinding grain or pumping water) or a generator can
convert this mechanical power into electricity to power homes,
businesses, schools, and the like.
• Wind turbines, like aircraft propeller blades, turn in the moving air
and power an electric generator that supplies an electric current.
Simply stated, a wind turbine is the opposite of a fan. Instead of
using electricity to make wind, like a fan, wind turbines use wind to
make electricity. The wind turns the blades, which spin a shaft,
which connects to a generator and makes electricity.

6.  Geothermal energy
• Geothermal energy is the heat from the Earth. It's clean and sustainable.
Resources of geothermal energy range from the shallow ground to hot
water and hot rock found a few miles beneath the Earth's surface, and
down even deeper to the extremely high temperatures of molten rock
called magma
• In the United States, most geothermal reservoirs of hot water are located in
the western states, Alaska, and Hawaii. Wells can be drilled into
underground reservoirs for the generation of electricity. Some geothermal
power plants use the steam from a reservoir to power a turbine/generator,
while others use the hot water to boil a working fluid that vaporizes and
then turns a turbine.

7.  Tidal energy
• Tidal energy, sometimes called tidal power, is the power
achieved by capturing the energy contained in moving water
in tides and open ocean currents.
• There are two types of energy systems that can be used to
extracted energy: kinetic energy, the moving water of rivers,
tides and open ocean currents; and potential energy from the
difference in height (or head) between high and low tides. The
first method - generating energy from tidal currents - is
becoming more and more popular because people believe
that it does not harm the environment as much as barrages or
dams. Many coastal sites worldwide are being examined for
their suitability to produce tidal (current) energy

9.  advantages
• One major advantage with the use of renewable energy is that as it
is renewable it is therefore sustainable and so will never run out.
• Even more importantly, renewable energy produces little or no
waste products such as carbon dioxide or other chemical pollutants,
so has minimal impact on the environment.
• Renewable energy projects can also bring economic benefits to
many regional areas, as most projects are located away from large
urban centres and suburbs of the capital cities. These economic
benefits may be from the increased use of local services as well as
tourism