Res poly unit i (3)ppt

RENEWABLE ENERGY SOURCES
(22033 ) POLYTECHNIC SYLLABUS
Unit I (3/3)
FUNDAMENTALS OF ENERGY
- C.Coomarasamy
Formerly Professor, JRPC, Trichy
(2012-2013)

UNIT I (3/3)-FUNDAMENTALS OF ENERGY
 Introduction to Energy-Energy consumption and standard of
living-classification of energy resources-consumption trend of
primary energy resources
 -importance of renewable energy sources-energy chain-
common forms of energy-advantages and disadvantages of
conventional energy sources-salient features of
nonconventional energy sources-environmental aspects of
energy
 -energy for sustainable development-energy density of various
fuels-availability of resources and future trends.
 Energy scenario in India – Overall production and
consumption-Availability of primary energy resources:
 Conventional, Non-Conventional-Estimated potential and
achievement-Growth of energy sector and its planning in India
–
 Energy conservation: Meaning and importance.
2

1.13 AVAILABILITY OF RESOURCES AND FUTURE TRENDS
3

1.13 AVAILABILITY OF RESOURCES AND FUTURE
TRENDS
1.13.A. Conventional Resources
(i) Fossil Fuels
Fossil fuels are so called because these are in fact the fossils of
old biological life that once existed on the surface of the
earth.
It is formed in several parts of the earth at varying depths, during
several million years by slow decomposition and chemical
actions of buried organic matter under favorable
pressure, heat and bacterial marine environment.
The fossil fuels include coal, oil and gas.
Fossil fuels have been a major source of energy since about
1850, the start of the industrial era. The fossil fuel age is
expected to cover only a span of 1000 years of human history
(1850-2850).
Presently, we are passing through the peak period of the fossil age.
As per an estimate, if the world continues to consume fossil fuels
at year 2006 rates, reserves of coal will last 200
years, oil - 40 years and gas - 70 years.
4

(i) Fossil Fuels
TRENDS
5

TRENDS
6

(I) FOSSIL FUELS
TRENDS
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(I) FOSSIL FUELS
8

.
 .
9

TRENDS
(ii) Hydro Resources
Among all renewables, hydro power is the most advanced and
flexible source of power.
- a well developed and established source of electric power.
Due to requirement of huge capital investment and strong
environmental concerns about large plants, only about
one-third of the realistic potential has been tapped so far.
From about 1880 hydro turbines are used, a large number of large
and medium sized hydro schemes have been developed.
The global installed generating capacity of
hydro power is about 627,000 MW.
Hydro installations and plants are long lasting (turbine life is
about 50 years).
This is due to continuous steady operation without high
temperature or other stresses.
Therefore, it often produces electricity at low cost with
consequent economic benefits. 10

TRENDS
11

TRENDS
(iii) Nuclear Resources
U 235, U233(isotopes of uranium) and Pu 239(plutonium)are
used as nuclear fuels in nuclear reactors (thermal reactors) and
are known as
fissile (or fissionable) materials.
Out of these, only U235 occurs in nature.
U233 from Th 232(thorium) and
Pu 239 are produced from U238 in Fast Breeder Reactors
(FBRs).
Th232 and U238 are known as fertile materials.
Natural uranium contains 0.71% of U235 and 99.29 % of U238
Currently there are around 440 nuclear power plants in the world
generating about 1/6 th world’s electricity.
Uranium reserves in the world are small (expected to last hardly
for 59 years at present, i.e., at the 2008 rate of consumption) and
its recovery is expensive.
12

NUCLEAR RESOURCES
.
TRENDS
13

B. Non-conventional Sources
Non-conventional technologies are presently under the
development stage. At present, their share is very small.
(i) Solar Energy
Solar energy can be a major source of power and can be utilized by
using thermal and photovoltaic conversion systems.
The solar radiation received on the surface of the earth on a
bright sunny day at noon is approximately 1 kW/m 2.
The earth continuously intercepts solar power of 178 billion
MW, which is about 10,000 times the world’s demand.
But so far, it could not be developed on a large scale.
According to one estimate, if all the buildings of the world are
covered with solar PV panels, it can fulfill electrical power
requirements of the world.
Solar PV power is considered an expensive source of power.
TRENDS
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TRENDS
15

TRENDS
16

TRENDS
17

TRENDS
(ii) Wind Energy
The power available in the winds flowing over the earth surface is
estimated to be 1.6 10 *7 MW , which is more than the
present energy requirement of the world.
Wind power has emerged as the most economical of all renewable
energy sources.
The installation cost of wind power is Rs 4 crore/ MW.
Wind power installations world wide have crossed 47,317 MW.
There has been remarkable growth of wind-power installation in the
world. Wind-power generation is the fastest growing energy
source.
It is expanding at a rate of more than 30 % annually.
18

TRENDS
19

Savonius Wind TurbineDarrieus Wind Turbine
TRENDS
20

TRENDS
(iii) Biomass EnergyEnergy resources available from animal and
vegetation are called biomass energy resources.
This is an important resource for developing
countries, especially in rural areas.
The principal biomass resources are:
 Trees (wood, leaves and forest industry waste)
 Cultivated plants grown for energy
 Algae and other vegetation from oceans and lakes
 Urban waste (municipal and industrial waste)
 Rural waste (agricultural and animal waste, crop residue, etc.
Solar energy absorbed by plants (through the photosynthesis
process) is estimated to be 2 10* 21 J/year. Biomass
material may be transformed by chemical or biological
processes to produce intermediate bio-fuels such as biogas
(methane), producer gas, ethanol and charcoal.
21

.
.
TRENDS
22

23

24

TRENDS
(iv) Geothermal Energy
Geothermal energy is derived from
huge amounts of
stored thermal energy in the
interior of the earth, though its
economic recovery on the
surface of the earth
is not feasible everywhere.
Its overall contribution in
total energy requirement is
negligible.
However, it is a
very important resource locally.
25

TRENDS
26

TRENDS
27

.
.
TRENDS
28

TRENDS
(v) Ocean Tidal Energy :Tidal energy is a form of hydro
power that converts energy of ocean tides into electricity
or other useful forms of power.
It is in the developing stage and although not yet widely
used, tidal power has potential for future electricity
generation.
Tides are more predictable than wind energy and solar power.
29

TIDAL ENERGY
When tides comes into the shore, they can be trapped in
reservoirs behind dams.
Then when the tide drops, the water behind the dam can be let
out just like in a regular hydroelectric power plant.
Tidal energy has been used since about the 11th Century, when
small dams were built along ocean estuaries and small streams.
The tidal water behind these dams was used to turn water wheels
to mill grains.
In order for tidal energy to work well, you need large increases in
tides.
An increase of at least 16 feet between low tide to high tide is
needed.
There are only a few places where this tide change occurs around
the earth. Some power plants are already operating with this idea.
One plant in France(in 1966 La Rance Station)makes enough
energy from tides (240 megawatts) to power 240,000 homes.
It is more than 10 times the power of the next largest tidal station
in the world, the 17 megawatt Canadian Annapolis station.
TRENDS
30

TIDAL POWER
Tidal power, also called tidal energy, is a form of hydropower that
converts the energy of tides into useful forms of power - mainly
electricity.
Although not yet widely used, tidal power has potential for future
electricity generation.
Tides are more predictable than wind energy and solar power.
Among sources of renewable energy, tidal power has
traditionally suffered from relatively high cost and limited
availability of sites with sufficiently high tidal ranges or flow
velocities, thus constricting its total availability.
However, many recent technological developments and
improvements, both in design (e.g. dynamic tidal power, tidal
lagoons) and turbine technology (e.g. new axial turbines, cross
flow turbines), indicate that the total availability of tidal power
may be much higher than previously assumed, and that
economic and environmental costs may be brought down to
competitive levels.
TRENDS
31

.
TRENDS
32

TRENDS
(vi) Ocean Wave Energy
Wave power refers to the energy of ocean surface waves and
the capture of that energy to do useful work.
Good wave power locations have a flux of about 50 kilowatts
per metre of shoreline.
As per an estimate, the potential for shoreline-based wave power
generation is about 50,000 MW.
Deep-water wave-power resources are truly
enormous, but perhaps
impractical to capture.
33

WAVE POWER
Wave power is the transport of energy by ocean surface waves, and
the capture of that energy to do useful work —
for example, electricity generation, water desalination, or the
pumping of water (into reservoirs).
Machinery able to exploit wave power is generally known as a wave
energy converter (WEC).
Wave power is distinct from the diurnal flux of tidal power and the
steady gyre of ocean currents.
Wave power generation is not currently a widely employed
commercial technology although there have been attempts at using
it since at least 1890.
In 2008, the first experimental wave farm was opened in Portugal, at
the Aguçadoura Wave Park.
TRENDS
34

WAVE POWER
.
TRENDS
35

(vii) Ocean Thermal Energy Conversion
OTEC technology
is still in
its infant stages.
Conceptual designs of small OTEC plants
have been finalized.
Their commercial prospects are
quite uncertain.
The potential is likely to be more than
that of tidal or wave energy.
TRENDS
36

OCEAN THERMAL
ENERGY CONVERSION
 .
TRENDS
37

.
OCEAN THERMAL
ENERGY CONVERSION
TRENDS
38

ENERGY – RENEWABLE AND NON-RENEWABLE
SOURCES
1.14 ENERGY SCENARIO IN INDIA
39

1.14.1 OVERALL PRODUCTION AND CONSUMPTION
 India is both a major energy producer and consumer.
 India currently ranks as the world’s
eleventh greatest energy
producer,
accounting for about
2.4% of the world’s total annual energy
production,
and as the world’s
sixth greatest energy consumer, accounting for
3.3% of the world’s total annual energy consumption.
 Thus,
India is a net energy importer, mostly due
the large imbalance between
oil production and
consumption.
40

 Out of 1, 57,229 MW total installed capacities India currently has
15,789 MW of installed
renewable energy sources
 1,00,598 MW of
Thermal power
- 64.6 per cent of the
total installed capacity,
 36,863 MW of
Hydel power plants come next with
24.7 percent of the
total an installed capacity
1.14.1 OVERALL PRODUCTION AND CONSUMPTION
41

1.14.2 AVAILABILITY OF PRIMARY ENERGY RESOURCES
A. Conventional
(i) Fossil Fuel
India has vast reserves of coal, the fourth largest in the world after
the USA, Russia and China.
According to a rough estimate, the total recoverable coal in India
is 90 billion tonne, about 10% of the world’s total.
With the present rate of consumption, India will have enough coal for
about 300 years.
We have only 0.6% of the world’s oil and gas reserves
Oil and gas represent over 40 per cent of the total energy
consumption in India.
About 35% of oil needs are met through domestic production
and the balance 65% through imports.
Crude oil reserves are estimated as 600 million tonne, enough
to last about 22 years at the present rate, if no further discovery is
made.
42

Natural gas reserves are estimated as 1000 billion m 3, enough
to last for 30 years, if no further discovery is made.
Oil and gas reserves are insufficient even for the transportation
sector.
The domestic production is decreasing slowly.
However, recent findings of gas reserves in Rajasthan and the
Krishna–Godavari basin off the Vishakhapatnam coast may change
the trend.
The actual impact will be known once these resources are fully
developed and production begins.
(ii) Hydro Resources
India stands seventh in the list of nations with hydro
resources with a total potential of100,000 M W of which approximately
36,033 MW has been developed.
Huge installation cost , environmental and social problems are
major difficulties in its development. 43

(iii) Nuclear Resources
India has modest reserves of uranium, mostly located at
Jadugoda, Jharkhand.
Out of the total electrical power generation, 2.8% is being
generated by nuclear means.
Nuclear-power generation is planned to reach 10,280 MW by the
year 2012 and 20,000 MW by 2020.
Thorium is available in abundance in India in the form of
monazite (ore) in the sand beaches of Kerala.
The economically viable reserve of thorium in India is estimated
at 3,00,000 tonnes, which is 25% of the world’s thorium
reserves.
Thorium is a fertile material, which is converted into a fissionable
material U 233 in an FBR. (Fast Breeder Reactors)
The U 233 so obtained may be used in a normal thermal reactor
such as PHW R. (pressurized heavy water reactor)
44

B. Non-conventional
Located in the tropical region, India is endowed with
abundant renewable energy
resources, i.e., solar, wind and
biomass including agricultural residue which are perennial in
nature.
Harnessing these resources is best suited to meet the energy
requirement in rural areas in a decentralized manner.
India has the potential of generating more than 1,00,000 MW from
non-conventional resources.
(i) Wind Energy
The highly successful wind power programme in India was
initiated in 1983–84 and is entirely market driven.
This sector has been growing at over 35% in the last three years.
India currently (year 2008) stands fourth in the world among
countries having installed large capacity wind generators, after
Germany, USA and Spain.
45

(ii) Solar Energy
India receives a solar energy equivalent of more than 5,000
trillion kWh per year, which is far more than its total annual
consumption.
The daily global radiation is around 5 kWh per sq. m per day
with sunshine ranging between 2300 and 3200 hours per year in
most parts of India.
Though the energy density is low and the availability is not
continuous, it has now become possible to harness this
abundantly available energy very reliably for many purposes
by converting it to usable heat or through direct generation of
electricity.
The conversion systems are modular in nature and can be
appropriately used for decentralized applications.
46

Solar Thermal Energy Programme
Use of solar thermal energy is being promoted f or water
heating, cooking, drying and space heating through various
schemes.
The government is proposing to make solar-assisted water
heating mandatory in certain categories of buildings through
amendments in the building bylaws.
Bangalore has been declared a solar thermal city with special
attention to popularize solar water heaters, and Thane in Mumbai is
to follow soon.
Solar Photovoltaic Programme
Solar PV energy is being used for solar lanterns, home-lighting
systems, street lighting systems, solar water pumps and
power plants.
47

(iii) Biomass Energy
A large quantity of biomass is available in our country in the
form of
dry waste like agro residues, fuel wood, twigs, etc., and
wet wastes like cattle dung, organic effluents, sugarcane
bagasse, banana stems, etc.
These plants require little care, can be grown on fallow land and
can survive in harsh climatic conditions.
Energy farming may be adopted in marginal and infertile lands of
the country.
(iv) Small Hydro Resources
Hydro resources of capacity
less than 25 MW are called
small, less than 1 MW are
called mini and less than
100 kW are called micro hydro resources.
The total potential is 15,000 MW out of which
2,015 MW has been realized by approximately 611 plants. 48

(v) Geothermal Energy
The potential in geothermal resources in the country is
10,000 MW .
As a result of various resource assessment studies/surveys, nearly
340 potential hot springs have been identified throughout
the country.
Most of them are low-temperature hot-water resources and can
best be utilized for direct thermal applications.
Only some of them can be considered
suitable for electrical power generation.
The geothermal reservoirs suitable for power generation have been
located at Tattapani in Chhattisgarh and Puga valley of
Ladakh, Jammu and Kashmir.
(vi) Ocean Tidal Energy
There is no functional tidal plant at present and the
total potential has been estimated as 9,000 MW.
Three sites have been identified for development of tidal energy. 49

(vii) Ocean Wave and OTEC Resources
A 150-kW pilot plant has been installed at Vizhingum harbour near
Thiruvananthapuram, Kerala.
The average potential (annual basis) for Indian coasts has been
estimated at around 0.02 MW/m of wave front.
There is a proposal for an OTEC plant at the Minicoy Island of
Lakhshdweep.
Emerging technologies like ‘fuel cell’ and ‘hydrogen energy’
are suited for stationary and portable power generation, which
suits transportation purposes.
In view of the growing importance of fuel cells and
hydrogen, a National Hydrogen Energy Board has been
created.
50

1.14.3 ESTIMATED POTENTIAL AND ACHIEVEMENT
 The country has an estimated renewable energy potential of
around 85,000 MW from commercially exploitable sources:
 Wind, 45,000 MW; small hydro, 15,000 MW and
 biomass/bio energy, 25,000 MW. In addition the potential to
generate
 35 MW per square km using solar photovoltaic and solar thermal
energy.
 The Government of India has outlined ambitious capacity expansion
and investment plans for the eleventh five year plan period (FY
2007- FY 2012).
 It has proposed an addition of 15,000 MW of Renewable Energy
generation capacities during the period.
 Wind Power projects form 70 percent (10,500 MW) of the proposed
capacity addition, while Small Hydro Projects (SHP) accounts for
9.3 per cent (1,400 MW).
 The total investments on development of RE during the plan period
is expected to be about USD 2 billion. 51

No. Sources / Systems EstimatedPotential CumulativeAchievements
(upto 31.12.2009)
1. Biomass Power (Agro residues) 16,881 MW 834.50 MW
2. Wind Power 48,500 MW 10925.00 MW
3. Small Hydro Power (upto 25 MW) 15,000 MW 2558.92 MW
4. Cogeneration-bagasse 5,000 MW 1302.00 MW
5. Waste to Energy 2,700 MW 65.01 MW
6. Solar Power 50 MW/sq.km. 6.00 MW
Sub Total (A) 88,081 MW 15691.43 MW
7 Biomass Power /Cogen.(non-bagasse) 210.57 MW
8. Biomass Gasifier 109.62 MWeq
9. Waste-to- Energy 37.97 MWeq
10. Solar PV PowerPlants and StreetLights 2.39 MWp
11. Aero-Generators/Hybrid Systems 0.89 MW
Sub Total (B) 361.44 MWeq
Total ( A + B ) 16052.87 MW
B. Off-grid/Distributed Renewable Power (including Captive/CHP plants)
A. Details of Estimated Renewable Energy potential & Cumulative
Achievements of power from renewables
52

 India is endowed with abundant primary energy sources;
fossil, renewable and unconventional.
 Coal dominates the country’s energy mix with a robust
52% share in primary energy consumption, followed by
 oil at 30% and
 gas at 10%.
 Other sources include 2% hydroelectricity and less than
a percent nuclear energy.
 The consumption profile in terms of primary sources is not matched
by indigenous production profile, creating concerns about energy
security.
 Import dependence of oil consumption is currently about
75%, which is projected to increase to 80% by 2016-17.
1.14.4 GROWTH OF ENERGY SECTOR AND
ITS PLANNING IN INDIA
53

 Import component of gas is currently ruling at
19%, slated to increase to 28% by 2016-17.
 Similarly, coal import is expected to rise from about
90 million tons at present to over 200 million tons in 2016-17.
 As per present estimate
85% of electric power generation is dependent on
oil, natural gas and coal.
 Even though India has abundant quantities of coal, it is constrained
to regional locations, high ash content, affecting the
thermal efficiency of power plants, and also there are
environmental concerns.
54

ENERGY INDEPENDENCE BY 2030 *
 By 2030, the total energy requirement for the country would increase
to 400,000 MWs from the existing 185,000 MWs.
 Ideally India has to plan for 215,000 MWs of power to be realized from
renewable energy resources like hydel, wind, solar, nuclear and
conversion of municipal waste into energy by 2030.
 The country has capability to generate additional
50,000 MWs of hydel power by creating regional waterways.
 India can generate solar energy to the extent of 60,000 MWs by having
large scale solar power.
 Gujarat State has already generated 680 MWs of solar electric
power through public-private partnership program and the power is
being fed to the grid.
 India has to generate 50,000 MWs of nuclear power, particularly using
the thorium route within the next decade and has
to generate 65,000 MWs of power using wind energy. If we work on
these targets, we will be getting nearly 225,000 MWs of electric power.
55

 Here we have to consider the reduction in load factor in
solar, wind and hydel which will necessitate generation of
20 to 30% excess power beyond the 400,000 MWs.
 This can certainly be achieved by
converting all the municipal wastes into electric energy which can
easily generate over 10,000 MWs of power.
 Movement towards energy independence would also demand
accelerated work in operationalizing the production of energy from the
coal sector
through integrated gasification and combined cycle route, so that
the existing coal based power plant get clean coal and substantially
reduce the carbon-di-oxide dumping in atmosphere.
--------------------------------------------------------------------------------------------
* Ref- Paper presentation by Dr. DC Patra, Ph. D (Petroleum
Economics), Chief Manager, LPG Strategy Bharat Petroleum
Corporation, Mumbai
ENERGY INDEPENDENCE BY 2030 *
56

1.15 ENERGY CONSERVATION:
MEANING AND IMPORTANCE
Energy conservation refers to efforts made
to reduce energy consumption.
Energy conservation can be achieved through
increased efficient energy use, in conjunction with
decreased energy consumption and/or
reduced consumption from conventional energy sources.
We depend on energy for almost everything in our lives.
We wish to make our lives comfortable, productive and enjoyable.
Hence even if the outside temperature rises a little, we immediately
switch on the air conditioner to keep our house cool.
This is again using up of energy.
Unfortunately, what we do not realize is that
we have starting taking things for granted and
we have started wasting energy unnecessarily.
57

Most of us forget that
energy is available in abundance but
it is limited and hence to maintain
the quality of life, it is important that
we use our
energy resources wisely.
If we do not conserve
energy, the energy
will exhaust and
we will have nothing to use.
Also, energy conservation is also important when it comes to climate
change.
Currently, erratic climates and climatic changes are the greatest
threats that we are facing today.
Hence it is important to
conserve energy.
58

 As per the energy policy of GOI power to be made available to all by
2012. One of the strategies to improve power scenario includes
promotion of energy efficiency and its conservation in the country, this is
found to be the most cost effective option to augment the gap between
demand and supply.
Nearly 25,000 MW of capacity creation through energy efficiency in
the electricity sector alone has been estimated in India.
( up dated on Monday, April 18, 2011)
 National Productivity Council (NPC), an autonomous organization under
the Ministry of Commerce, Government of India, was asked by BEE to
undertake the study of energy saving potential in all 35 states / UTs.
 The study focused only on estimation of the total electricity consumption
and saving potential in different sectors of each state / UT.
 The potential for savings is about 15% of the electricity
consumption.
 The sector wise aggregated potential at the national level is as under:
59

S.No. Sector Consumption
(Billion KWh)
Saving Potential
(Billion KWh)
1. Agriculture Pumping 92.33 27.79
2. Commercial Buildings/
Establishments with
connected load > 500 KW
9.92 1.98
3. Municipalities 12.45 2.88
4. Domestic 120.92 24.16
5. Industry (Including SMEs) 265.38 18.57
Total 501.00 75.36
60

 Seeing the huge scope of energy conservation the GoI with state
governments is promoting investments through public-private
partnerships in tapping renewable energy resources from
mini hydro, solar, biomass, urban/industrial
waste, cogeneration, etc.
 For this purpose the State Governments are notifying nodal agencies
for carbon credits under the Clean Development Mechanism (CDM).
 All project developers (private as well as Government) can have
assistance of these designated agencies in terms of seeking carbon
credits under CDM for both supply new and renewable sources of
energy as well as demand (energy efficiency) side projects.
 With a view to intensifying efforts towards Energy Conservation Action
Plan to pursue a harmonious growth in energy efficiency different state
government has nominated different organization to act as nodal agency
the purpose of these is to implement energy efficiency programmes as
per guide lines of BEE.(Bureau of Energy Efficiency.)
1.15 ENERGY CONSERVATION: MEANING AND
IMPORTANCE
61

 The major objectives of the Energy Conservation Action Plan are to:
 · Raise the profile of energy conservation movement with the active
participation of the stakeholders, in consonance with the national
objectives of reducing the energy intensity of the economy.
 · Identify and implement cost-effective energy efficiency programs
through a sustainable mechanism;
 · Encourage energy efficiency activities by drawing upon the
prevailing best practices relevant to the state and keeping in mind the
national programs and activities being launched by BEE.
 These include the concerns of state electricity regulator in the domain of
energy end-use efficiencies and focused
demand-side management (DSM) initiatives.
IMPORTANCE
62

 · Encourage a spurt towards professional activities with adequate
emphasis on self regulation and market principles, and monitoring and
evaluation of programs through quantitative metrics (performance
indicators).
 · Create consumer awareness vis-à-vis energy conservation and
energy efficiency consumer information and provide training
opportunities for key professionals such as energy managers and
auditors, building designers, government officials, and facility managers.
 · Protect and enhance the local, national and global environment.
IMPORTANCE
63

 The Governments are announcing the mandatory following measures
applicable to the governmental sector:-
 · Issuing notifications regarding the mandatory use of solar water
heating systems,
 · Use of compact fluorescent lamps,
 · Use of BIS marked pump sets in government and private
buildings, including industries and
 · Use of solar water heating systems made mandatory in buildings
having an area of more than 500 sq yard.
IMPORTANCE
64

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