3. Classification of Energy Sources
Nonrenewable Renewable Secondary
OIL
Natural Gas
Coal
Nuclear energy
Sun energy
Hydro energy
Wind energy
Geothermal energy
Biomass energy
Tidal energy
Electricity
Hydrogen
5. Energy Resources
Primary energy resources
• Available in nature in raw form e.g coal, petroleum, oil, natural gas,
fire wood, wind, water, uranium ore, solar irradiation, geothermal, ocean
waves, tides, bio mass etc
Intermediate energy
• Useful form produced by processing primary resources such as coal may be
gasified
Secondary energy resources
• Supplied to the user for consumption e.g electrical energy, liquid
petroleum, gas etc
Primary
energy
source
processing Electrical consumer
processing Secondary transport consumer
6.
7. Forms of Energy
• Kinetic energy K.E=1/2 mv2
• Potential Energy P.E=mgh
• Heat Energy Intrinsic energy of all combustible substances
• Chemical energy Tied-up in fossil fuels
Chemical energy in food helps us to sustain our life
• Radiant energy Solar radiations
• Nuclear energy matter can be changed into energy. E=mc2
8. Portfolio of affordable, reliable &
environmentally responsible technologies
Energy technology objectives
Driving cost of electricity down
Efficiency
Reliability
Emissions
Efficient
Diverse
Nuclear
Coal
Gas
Wind
Oil
Geothermal
Biomass
Hydro
Solar
+
9. Concept of Renewable Energy
• Renewable energy sources also called non-conventional energy,
are sources that are continuously replenished by natural processes.
For example, solar energy, wind energy, bio-energy - bio-fuels
grown sustain ably), hydropower etc., are some of the examples of
renewable energy sources.
• A renewable energy system converts the energy found in sunlight,
wind, falling-water, sea waves, geothermal heat, or biomass into a
form, we can use such as heat or electricity.
• Renewable energy sources are essentially flows of energy, whereas
the fossil and nuclear fuels are, in essence, stocks of energy
10.
11. Solar Energy
• Solar energy is the most readily available and free source of
energy since prehistoric times. It is estimated that solar energy
equivalent to over 15,000 times the world's annual commercial
energy consumption reaches the earth every year.
12. Solar Thermal Energy Application
• In solar thermal route, solar energy can be converted into
thermal energy with the help of solar collectors and receivers
known as solar thermal devices.
• The Solar-Thermal devices can be classified into three
categories:
– Low-Grade Heating Devices - up to the temperature of 100°C.
– Medium-Grade Heating Devices -up to the temperature of 100°-300°C
– High-Grade Heating Devices -above temperature of 300°C
13. Solar energy
• Solar energy technologies can be loosely divided into two categories: solar
thermal systems and solar electric or photovoltaic (PV)
Examples of solar power applications are illustrated in table .
15. Wind Energy
Wind energy is basically harnessing of wind power to produce
electricity.
The kinetic energy of the wind is converted to electrical energy.
When solar radiation enters the earth's atmosphere, different regions
of the atmosphere are heated to different degrees because of earth
curvature. This heating is higher at the equator and lowest at the
poles.
Since air tends to flow from warmer to cooler regions, this causes
what we call winds, and it is these airflows that are harnessed in
windmills and wind turbines to produce power.
Wind power is not a new development as this power, in the form of
traditional windmills -for grinding corn, pumping water, sailing
ships - have been used for centuries.
Now wind power is harnessed to generate electricity in a larger
scale with better technology.
18. Bio Energy
• Biomass is a renewable energy resource derived from the
carbonaceous waste of various human and natural activities.
• It is derived from numerous sources, including the by-products
from the wood industry, agricultural crops, raw material from
the forest, household wastes etc.
• There are technologies for bio-energy using liquid and gaseous
fuel, as well as traditional applications of direct combustion.
• The conversion process can be physical (for example, drying,
size, reduction or densification), thermal(as in carbonization)
or chemical (as in biogas production).
• The end result of the conversion process may be a solid, liquid
or gaseous fuel and this flexibility of choice in the physical
form of the fuel is one of the advantages of bio-energy over
other renewable energy sources.
21. Hydro
• Hydropower is the extraction of energy from falling water
(from a higher to a lower altitude) when it is made to pass
through an energy conversion device, such as a water turbine
or a water wheel.
• A water turbine converts the energy of water into mechanical
energy, which in turn is often converted into electrical energy
by means of a generator.
• Alternatively, hydropower can also be extracted from river
currents when a suitable device is placed directly in a river.
The devices employed in this case are generally known as
river or water current turbines1 or a “zero head” turbine.
24. Geothermal
• Geothermal is energy available as heat emitted from within the earth,
usually in the form of hot water or steam.
• Geothermal heat has two sources: the original heat produced from the
formation of the earth by gravitational collapse and the heat produced
by the radioactive decay of various isotopes.
• It is very site dependent as the resource needs to be near surface and
can be used for heating and power generation purposes.
• High temperature resources (150° C+) can be used for electricity
generation, while low temperature resources (50-150° C) can be used
for various direct uses such as district heating and industrial
processing.
• Since the earth’s crust is continuously emitting heat towards its
surface at a rate of 40 million megawatts, geothermal is in principle
an inexhaustible energy source, with the centre of the earth having
cooled down by only about 2 per cent over the earth’s lifetime of
about 4 billion years.
