renew energy 1
TRANSCRIPT
1
Dr. Mandar M. Lele
Conventional
&
Non Conventional
Energy ResourcesPart- 1
T her ma l S
ys tems/ E
n er gy
2
Dr. Mandar M. Lele
T her ma l S
ys tems/ E
n er gy
a)Types of energy:- conventional and
non-conventional.
b)Need for harnessing alternative
energies to meet the increased
demand.
c) Methods of harnessing energies.
3
Dr. Mandar M. Lele
Fuels & CombustionFuels & Combustion
T her ma l S
ys tems/ Fu els
4
Dr. Mandar M. Lele
Fuels & CombustionFuels & Combustion
Introduction
Type of fuels
Performance evaluation
Energy efficiency opportunities
T her ma l S
ys tems/ Fu els
5
Dr. Mandar M. Lele
Energy ConversionEnergy Conversion
T her ma l S
ys tems/ Fu els
Oil burns to make heat -->Heat boils water -->Water turns to steam -->Steam pressure turns a turbine -->Turbine turns an electric generator -->Generator produces electricity -->Electricity powers light bulbs -->Light bulbs give off light and heat
6
Dr. Mandar M. Lele
IntroductionIntroduction
• Solar energy is converted to chemical energy through photo-synthesis in plants
• Energy produced by burning wood or fossil fuels
• Fossil fuels: coal, oil and natural gas
The Formation of FuelsT her ma l S
ys tems/ Fu els
7
Dr. Mandar M. Lele
Fuels & CombustionFuels & Combustion
Introduction
Type of fuels
Performance evaluation
Energy efficiency opportunities
T her ma l S
ys tems/ Fu els
8
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsUsage• Used extensively in industrial applications
Examples• Furnace oil
• Light diesel oil
• Petrol
• Kerosine
• Ethanol
• LSHS (low sulphur heavy stock)
T her ma l S
ys tems/ Fu els
9
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsDensity• Ratio of the fuel’s mass to its volume at 15 oC,
• kg/m3
• Useful for determining fuel quantity and quality
T her ma l S
ys tems/ Fu els
10
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsSpecific gravity• Ratio of weight of oil volume to weight of same water volume at a given temperature
• Specific gravity of water is 1
• Hydrometer used to measure
T her ma l S
ys tems/ Fu els Fuel oil
typeLDO(Light Diesel Oil)
Furnace oil LSHS (Low SulphurHeavy Stock)
Specific Gravity
0.85-0.87 0.89-0.95 0.88-0.98
Table 1. Specific gravity of various fuel oils (adapted from Thermax India Ltd.)
11
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsViscosity• Measure of fuel’s internal resistance to flow
• Most important characteristic for storage and use
• Decreases as temperature increases
Flash point• Lowest temperature at which a fuel can be heated so that the vapour gives off flashes when an open flame is passes over it
• Flash point of furnace oil: 66oC
T her ma l S
ys tems/ Fu els
12
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid Fuels
Pour point• Lowest temperature at which fuel will flow
• Indication of temperature at which fuel can be pumped
Specific heat• kCal needed to raise temperature of 1 kg oil by
1oC (kcal/kgoC)
• Indicates how much steam/electricity it takes to heat oil to a desired temperature
T her ma l S
ys tems/ Fu els
13
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsCalorific value• Heat or energy produced
• Gross calorific value (GCV): vapour is fully condensed
• Net calorific value (NCV): water is not fully condensed
T her ma l S
ys tems/ Fu els
Fuel Oil Gross Calorific Value (kCal/kg)Kerosene 11,100Diesel Oil 10,800L.D.O 10,700Furnace Oil 10,500LSHS 10,600
14
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsSulphur content• Depends on source of crude oil and less on the refining process
• Furnace oil: 2-4 % sulphur
• Sulphuric acid causes corrosion
Ash content• Inorganic material in fuel
• Typically 0.03 - 0.07%
• Corrosion of burner tips and damage to materials /equipments at high temperatures
T her ma l S
ys tems/ Fu els
15
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsCarbon residue• Tendency of oil to deposit a carbonaceous solid residue on a hot surface
• Residual oil: >1% carbon residue
Water content• Normally low in furnace oil supplied (<1% at
refinery)
• Free or emulsified form
• Can damage furnace surface and impact flame
T her ma l S
ys tems/ Fu els
16
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsStorage of fuels• Store in cylindrical tanks above or below
the ground
• Recommended storage: >10 days of normal consumption
• Cleaning at regular intervals
T her ma l S
ys tems/ Fu els
17
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Liquid FuelsT her ma l S
ys tems/ Fu els
Fuel OilsPropertiesFurnace Oil L.S.H.S L.D.O
Density (Approx. g/cc at 150C)
0.89-0.95 0.88-0.98 0.85-0.87
Flash Point (0C) 66 93 66Pour Point (0C) 20 72 18G.C.V. (Kcal/kg) 10500 10600 10700Sediment, % Wt. Max.
0.25 0.25 0.1
Sulphur Total, % Wt. Max.
< 4.0 < 0.5 < 1.8
Water Content, % Vol. Max.
1.0 1.0 0.25
Ash % Wt. Max. 0.1 0.1 0.02
Typical specifications of fuel oils(adapted from Thermax India Ltd.)
18
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid FuelsCoal classification• Anthracite: hard and geologically the
oldest
• Bituminous
• Lignite: soft coal and the youngest
• Further classification: semi- anthracite, semi-bituminous, and sub-bituminous
T her ma l S
ys tems/ Fu els
19
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels
Physical properties• Heating or calorific value (GCV)
• Moisture content
• Volatile matter
• Ash
Chemical properties• Chemical constituents: carbon, hydrogen,
oxygen, sulphur
T her ma l S
ys tems/ Fu els
20
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Physical properties)
Heating or calorific value• The typical GCVs for various coals are:
Parameter Lignite(Dry
Basis)
Indian Coal
Indonesian Coal
South African Coal
GCV (kCal/kg)
4,500 4,000 5,500 6,000
T her ma l S
ys tems/ Fu els
21
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Physical properties)T her ma l S
ys tems/ Fu els
Moisture content• % of moisture in fuel (0.5 – 10%)
• Reduces heating value of fuel
• Weight loss from heated and then cooled powdered raw coal
Volatile matter• Methane, hydrocarbons, hydrogen, CO, other
• Typically 25-35%
• Easy ignition with high volatile matter
• Weight loss from heated then cooled crushed coal
22
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Physical properties)T her ma l S
ys tems/ Fu els
Ash• Impurity that will not burn (5-40%)
• Important for design of furnace
• Ash = residue after combustion
Fixed carbon• Fixed carbon = 100 – (moisture + volatile matter + ash)
• Carbon + hydrogen, oxygen, sulphur, nitrogen residues
• Heat generator during combustion
23
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Physical properties)T her ma l S
ys tems/ Fu els
Proximate analysis of coal• Determines only fixed carbon, volatile matter,
moisture and ash
• Useful to find out heating value (GCV)
• Simple analysis equipment
Ultimate analysis of coal• Determines all coal component elements: carbon,
hydrogen, oxygen, sulphur, other
• Useful for furnace design (e.g flame temperature, flue duct design)
• Laboratory analysis
24
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Physical properties)Proximate analysis
Typical proximate analysis of various coals (%)
T her ma l S
ys tems/ Fu els
Indian Coal
Indonesian Coal
South African Coal
Moisture 5.98 9.43 8.5
Ash 38.63 13.99 17
Volatile matter
20.70 29.79 23.28
Fixed Carbon 34.69 46.79 51.22
25
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Chemical Properties)Ultimate analysis
Typical ultimate analysis of coal (%)
T her ma l S
ys tems/ Fu els
Parameter Indian Coal, % Indonesian Coal, % Moisture 5.98 9.43 Mineral Matter (1.1 x Ash) 38.63 13.99 Carbon 41.11 58.96 Hydrogen 2.76 4.16 Nitrogen 1.22 1.02 Sulphur 0.41 0.56 Oxygen 9.89 11.88 GCV (kCal/kg) 4000 5500
26
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Solid Fuels (Chemical Properties)Storage, Handling & Preparation• Storage to minimize carpet loss and loss due
to spontaneous combustion
• Reduce carpet loss: a) a hard surface b) standard concrete/brick storage bays
• Coal preparation before use is important for good combustion
T her ma l S
ys tems/ Fu els
27
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Gaseous FuelsAdvantages of gaseous fuels• Least amount of handling
• Simplest burners systems
• Burner systems require least maintenance
• Environmental benefits: lowest GHG and other emissions
T her ma l S
ys tems/ Fu els
28
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Gaseous FuelsClassification of gaseous fuels
T her ma l S
ys tems/ Fu els
(A) Fuels naturally found in nature-Natural gas-Methane from coal mines(B) Fuel gases made from solid fuel-Gases derived from coal-Gases derived from waste and biomass-From other industrial processes (C) Gases made from petroleum-Liquefied Petroleum gas (LPG)-Refinery gases-Gases from oil gasification(D) Gases from some fermentation
29
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Gaseous FuelsCalorific value• Fuel should be compared based on the net
calorific value (NCV), especially natural gas
Typical physical and chemical properties of various gaseous fuels
T her ma l S
ys tems/ Fu els
Fuel Gas
Relative Density
Higher Heating Value kCal/Nm3
Air/Fuel ratio m3/m3
Flame Temp oC
Flame speed m/s
Natural Gas
0.6 9350 10 1954 0.290
Propane 1.52 22200 25 1967 0.460
Butane 1.96 28500 32 1973 0.870
30
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Gaseous FuelsLiquefied Petroleum Gas (LPG)• Propane, butane and unsaturates, lighter C2 and heavier C5 fractions
• Hydrocarbons are gaseous at atmospheric pressure but can be condensed to liquid state
• LPG vapour is denser than air: leaking gases can flow long distances from the source
T her ma l S
ys tems/ Fu els
31
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Gaseous FuelsNatural gas• Methane: 95%
• Remaing 5%: ethane, propane, butane, pentane, nitrogen, carbon dioxide, other gases
• High calorific value fuel
• Does not require storage facilities
• No sulphur
• Mixes readily with air without producing smoke or soot
T her ma l S
ys tems/ Fu els
32
Dr. Mandar M. Lele
Type of FuelsType of Fuels
Comparing FuelsT her ma l S
ys tems/ Fu els
Fuel Oil Coal Natural Gas
Carbon 84 41.11 74Hydrogen 12 2.76 25
Sulphur 3 0.41 -Oxygen 1 9.89 TraceNitrogen Trace 1.22 0.75Ash Trace 38.63 -Water Trace 5.98 -
33
Dr. Mandar M. Lele
The amount of energy in heat units liberated by
unit quantity of a fuel is called its calorific value
(C.V.).
There are two cases to consider -
Higher Calorific Value (H.C.V.)
Lower Calorific Value (L.C.V.)
T her ma l S
ys tems/ Fu els
Type of FuelsType of Fuels
Calorific value of fuels
34
Dr. Mandar M. Lele
1. The Higher or Gross Calorific Value (H.C.V.)
This is the energy liberated.per kg, in the case of
solid or liquid fuels, or the energy liberated per m3,
in the case of gaseous fuels and, in all cases, when
the products of combustion are cooled to the
original fuel temperature.
T her ma l S
ys tems/ Fu els
Calorific value of fuels
Type of FuelsType of Fuels
35
Dr. Mandar M. Lele
2. The Lower or Net Calorific Value (L.C.V.)In most fuels there is a quantity of hydrogen present
and also the fuel may contain some moisture. When burnt, the hydrogen will form H2O and this, together with any moisture in the fuel, will appear as steam in the exhaust or flue. Now, in general, it is not convenient to cool the exhaust products sufficiently and hence the H2O leaves as steam. It has thus left without giving up its enthalpy of evaporation which is, therefore, not made available to the plant. For this reason, the lower or net calorific value of a fuel has been introduced.
T her ma l S
ys tems/ Fu els
Calorific value of fuels
Type of FuelsType of Fuels
36
Dr. Mandar M. Lele
T her ma l S
ys tems/ Fu els
This is determined by reducing the higher
calorific value by the amount of the enthalpy of
evaporation leaving in the H2O in the products.
Now the mass of H2O in the products/kg fuel
burnt
= (m+9H2) kg
Calorific value of fuels
Type of FuelsType of Fuels
37
Dr. Mandar M. Lele
The specific enthalpy of evaporation/kg steam,
which leaves with the products, is taken as 2442
kJ/kg. This is the specific enthalpy of evaporation
of steam at 25°C.
From this then,
L.C.V. = {H.C.V.-2442(m+9H2)} kJ/kg
where, m = mass moisture/kg fuel,
H2 = mass H2/kg fuel.
T her ma l S
ys tems/ Fu els
Calorific value of fuels
Type of FuelsType of Fuels
38
Dr. Mandar M. Lele
The determination of the calorific value of fuels (Calorimeter)
In the case of solid and some liquid fuels the
calorific value is usually determined in a bomb
calorimeter.
In the case of gaseous and some liquid fuels the
calorific value is determined in a gas calorimeter.
T her ma l S
ys tems/ Fu els
Calorific value of fuels
Type of FuelsType of Fuels
39
Dr. Mandar M. Lele
Fuels & CombustionFuels & Combustion
Introduction
Type of fuels
Performance evaluation
Energy efficiency opportunities
T her ma l S
ys tems/ Fu els
40
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
• Combustion: rapid oxidation of a fuel
• Complete combustion: total oxidation of fuel (adequate supply of oxygen needed)
• Air: 20.9% oxygen, 79% nitrogen and other
• Nitrogen: (a) reduces the combustion efficiency (b) forms NOx at high temperatures
• Carbon forms (a) CO2 (b) CO resulting in less heat production
Principles of CombustionT her ma l S
ys tems/ Fu els
41
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
• Control the 3 Ts to optimize combustion:
• Water vapor is a by-product of burning fuel that contains hydrogen and this robs heat from the flue gases
Principles of CombustionT her ma l S
ys tems/ Fu els
1T) Temperature
2T) Turbulence
3T) Time
42
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
Oxygen is the key to combustion
Principle of CombustionT her ma l S
ys tems/ Fu els
Bureau of Energy Efficiency, India, 2004
43
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
Stochiometric calculation of air required
Stochiometric air needed for combustion of furnace oil
Theoretical CO2 content in the flue gases
Actual CO2 content and % excess air
Constituents of flue gas with excess air
Theoretical CO2 and O2 in dry flue gas by volume
T her ma l S
ys tems/ Fu els
44
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
• Measure CO2 in flue gases to estimate excess air level and stack losses
Concept of Excess AirT her ma l S
ys tems/ Fu els
Carbon dioxide (%)
Exce
ss a
ir (%
)
Source: Bureau of Energy Efficiency, India, 2004
45
Dr. Mandar M. Lele
Performance EvaluationPerformance Evaluation
Concept of Excess AirT her ma l S
ys tems/ Fu els
Residual oxygen (%)
Exce
ss a
ir (%
)
Bureau of Energy Efficiency, India, 2004
• Measure O2 in flue gases to estimate excess air level and stack losses
46
Dr. Mandar M. LeleTraining Agenda: Fuels & Training Agenda: Fuels & CombustionCombustion
Introduction
Type of fuels
Performance evaluation
Energy efficiency opportunities
T her ma l S
ys tems/ Fu els
47
Dr. Mandar M. Lele
Preheating of combustion oil
Temperature control of combustion oil
Preparation of solid fuels
Combustion controls
Four main areasT her ma l S
ys tems/ Fu els
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
48
Dr. Mandar M. Lele
Purpose: to make furnace oil easier to pump
Two methods:• Preheating the entire tank
• Preheating through an outflow heater as the oil flows out
Preheating of Combustion Oil
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
T her ma l S
ys tems/ Fu els
49
Dr. Mandar M. Lele
To prevent overheating• With reduced or stopped oil flow
• Especially electric heaters
Using thermostats
Temperature Control of Combustion Oil
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
T her ma l S
ys tems/ Fu els
50
Dr. Mandar M. Lele
Sizing and screening of coal• Important for efficient combustion
• Size reduction through crushing and pulverizing (< 4 - 6 mm)
• Screen to separate fines and small particles
• Magnetic separator for iron pieces in coal
Preparation of Solid Fuels
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
T her ma l S
ys tems/ Fu els
51
Dr. Mandar M. Lele
Conditioning of coal:• Coal fines cause combustion problems
• Segregation can be reduced by conditioning coal with water
• Decrease % unburnt carbon
• Decrease excess air level required
Preparation of Solid Fuels
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
T her ma l S
ys tems/ Fu els
52
Dr. Mandar M. Lele
Blending of coal• Used with excessive coal fines
• Blending of lumped coal with coal containing fines
• Limits fines in coal being fired to <25%
• Ensures more uniform coal supply
Preparation of Solid Fuels
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
T her ma l S
ys tems/ Fu els
53
Dr. Mandar M. Lele
Energy Efficiency OpportunitiesEnergy Efficiency Opportunities
• Assist burner to achieve optimum boiler efficiency through the regulation of fuel supply, air supply, and removal of combustion gases
• Three controls:• On/Off control: burner is firing at full rate or it is
turned off
• High/Low/Off control: burners with two firing rates
• Modulating control: matches steam pressure demand by altering the firing rate
Combustion ControlsT her ma l S
ys tems/ Fu els
54
Dr. Mandar M. Lele
Non Conventional Energy Resources
T her ma l S
ys tems/ S
o lar En er gy
55
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
Solar Energy
Wind Energy
Tidal & Wave Energy
Biogas Energy
Non Conventional Energy Resources
56
Dr. Mandar M. Lele
Solar Energy
T her ma l S
ys tems/ S
o lar En er gy
Non Conventional Energy Resources
57
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
Non Conventional Energy Resources
58
Dr. Mandar M. Lele
What is Solar Energy?• Originates with
the thermonuclear fusion reactions occurring in the sun.
T her ma l S
ys tems/ S
o lar En er gy
•Represents the entire electromagnetic radiation (visible light, infrared, ultraviolet, x-rays, and radio waves).
59
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
60
Dr. Mandar M. Lele
How much solar energy?
The surface receives about 47% of the total solar energy that reaches the Earth. Only this amount is usable.
T her ma l S
ys tems/ S
o lar En er gy
61
Dr. Mandar M. Lele
Advantages of Solar Energy• 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!
T her ma l S
ys tems/ S
o lar En er gy
62
Dr. Mandar M. Lele
Disadvantages of Solar Energy
• 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.
T her ma l S
ys tems/ S
o lar En er gy
63
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
64
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
65
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
66
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
67
Dr. Mandar M. Lele
Putting Solar Energy to Use:Heating Water
• Two methods of heating water: passive (no moving parts) and active (pumps).
• In both, a flat-plate collector is used to absorb the sun’s energy to heat the water.
T her ma l S
ys tems/ S
o lar En er gy
• The water circulates throughout the closed system due to convection currents.
• Tanks of hot water are used as storage.
68
Dr. Mandar M. Lele
Heating Water: Active System
Active System uses antifreeze so that the liquid does not freeze if outside temp. drops below freezing.
T her ma l S
ys tems/ S
o lar En er gy
69
Dr. Mandar M. Lele
Heating Living Spaces
Passive Solar
Trombe Wall
Passively heated home in Colorado
T her ma l S
ys tems/ S
o lar En er gy
70
Dr. Mandar M. Lele
• A passively heated home uses about 60-75% of the solar energy that hits its walls and windows.
• The Center for Renewable Resources estimates that in almost any climate, a well-designed passive solar home can reduce energy bills by 75% with an added construction cost of only 5-10%.
• About 25% of energy is used for water and space heating.
• Major factor discouraging solar heating is low energy prices.
Heating Living Spaces
T her ma l S
ys tems/ S
o lar En er gy
71
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
72
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
73
Dr. Mandar M. Lele
Power Towers
Power tower in Barstow, California.
T her ma l S
ys tems/ S
o lar En er gy
74
Dr. Mandar M. Lele
Parabolic Dishes and Troughs
Because they work best under direct sunlight, parabolic dishes and troughs must be steered throughout the day in the direction of the sun.
Collectors in southern CA.
75
Dr. Mandar M. Lele
76
Dr. Mandar M. Lele
Direct Conversion into Electricity• Photovoltaic cells are
capable of directly converting sunlight into electricity.
• A simple wafer of silicon with wires attached to the layers. Current is produced based on types of silicon (n-and p-types) used for the layers. Each cell=0.5 volts.
• Battery needed as storage• No moving parts do no
wear out, but because they are exposed to the weather, their lifespan is about 20 years.
77
Dr. Mandar M. Lele
Solar Panels in Use• Because of their current costs, only
rural and other customers far away from power lines use solar panels because it is more cost effective than extending power lines.
• Note that utility companies are already purchasing, installing, and maintaining PV-home systems (Idaho Power Co.).
• Largest solar plant in US, sponsored by the DOE, served the Sacramento area, producing 2195 MWh of electric energy, making it cost competitive with fossil fuel plants.
78
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
79
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
80
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
81
Dr. Mandar M. Lele
Non Conventional Energy Resources
T her ma l S
ys tems/ S
o lar En er gy
82
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
Solar Energy
Wind Energy
Tidal & Wave Energy
Biogas Energy
Non Conventional Energy Resources
83
Dr. Mandar M. Lele
Wind Energy
T her ma l S
ys tems/ W
i nd En erg y
84
Dr. Mandar M. Lele
The kinetic energy of the wind can bechanged into other forms of energy, eithermechanical energy or electrical energy.
When the wind fills a boat sail, the boat is using wind energy to push it through the water.
What is Wind ?What is wind energy?
T her ma l S
ys tems/ W
ind En er gy
85
Dr. Mandar M. Lele
Wind Energy Through the Years
T her ma l S
ys tems/ W
ind En er gy
86
Dr. Mandar M. Lele
Theoretically, about 1 to 2% of the sun’s radiation turns intowind energy when it arrives at the earth, which is about ahundred times of all the energy consumed on the planet.
How is Wind Formed?
T her ma l S
ys tems/ W
ind En er gy
87
Dr. Mandar M. Lele
• All moving objects contain
kinetic energy.
• The kinetic energy
contained in wind can be
transferred to other objects,
such as boat sails, or
transformed into electrical
energy through wind turbine
generators.
How to Extract Wind Energy?
T her ma l S
ys tems/ W
ind En er gy
88
Dr. Mandar M. Lele
• Wind blows over the angledblades and results in a turningforce.• The force will turn the shaft,gearbox and generator, whichare all connected.• The gearbox increases therotational speed, enabling thegenerator to produce electricity.• The yaw control would turn therotor and nacelle to face thewind.
How is electricitygenerated by wind turbine?
T her ma l S
ys tems/ W
ind En er gy
89
Dr. Mandar M. Lele
Onshore wind farms continue to make up themajority of wind farms around the world.
Advantages• Lower construction costs compared with offshore wind farms, easy access for maintenance, relatively convenient to connect to power grids.
Constraints• Height restrictions for hilltop wind turbines, unsteady wind conditions, concerns over noise and visual impact on the environment.
Onshore Wind Farms
T her ma l S
ys tems/ W
ind En er gy
90
Dr. Mandar M. Lele
Offshore Wind Farms• They are typically constructed inregions with high populationdensities with few suitable sites.Advantages• Steady and stronger supply of wind than onshore wind farms, less visual impact, less likely to be affected by height restrictions than hilltop wind turbines.Constraints• Higher construction costs, subject to water depth restrictions (mostexisting off-shore installations are inwaters shallower than 20 m.
An offshore wind farm located atRodsand of Denmark, with 72 wind turbines, total installed capacity of 165.6 MW.
91
Dr. Mandar M. Lele
Installed Wind Power Capacity Worldwide
Rank Country Installed Capacity
1 Germany 16,629 MW
3 USA 6,740 MW
2 Spain 8,236 MW
GermanySchuby Wind Farm,near Schleswig,with installed capacityof 18 MW.
SpainLeitza-Beruete WindFarm, Navarre,Spain, with installedcapacity of19.2 MW
USAWhite Deer Wind Farm,Texas, withinstalled capacity of80 MW.
92
Dr. Mandar M. Lele
Denmark & China• Denmark has the world’s 4th-largest total installed wind power capacity at 3,118 MW ( end of 2004).• Wind energy made up over 18% of Danishelectricity consumption in 2004.• Most modern wind turbines adopt a three-bladed machine designed by Denmark. ( 40% of the world market in wind turbine manufacturing)• China ranks 10th in the world in terms of totalinstalled wind power capacity with 764 MW as ofthe end of 2004.
T her ma l S
ys tems/ W
ind En er gy
Case Study
93
Dr. Mandar M. Lele
Rejsby Hede WindFarm, in Denmark,consists of 40turbines with atotalinstalled capacityof 24 MW.
A wind farm inHuitengxile, InnerMongolia, consistingof 72 turbineswith a total installedcapacity of42.7 MW
T her ma l S
ys tems/ W
ind En er gy
94
Dr. Mandar M. Lele
• It is clean and does not pollute the airWind turbines do not emit greenhouse gases orcontribute to global warming.• It does not deplete resourcesEvery 1 million units of electricity generated bya wind turbine can offset approximately 350tonnes of coal.• It is more cost-effective than other forms ofrenewable energyAs wind energy technology matures,construction and operating costs continue todrop, providing greater cost effectiveness
Benefits of Wind Energy
T her ma l S
ys tems/ W
ind En er gy
95
Dr. Mandar M. Lele
Challenges of Wind Energy• It is intermittent andunpredictable
Wind turbine generator outputs are not controllable or predictable. Wind energy alone cannot be relied upon as the sole source of electricity.
• Wind farms occupy largeareas
Places with high population densities and land limitation often have difficulty finding the necessary space for wind farms
* Wind turbines canimpose adverse impacton the environmentImpact on migratingbirds. Create noise,visual blight.
96
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
Solar Energy
Wind Energy
Tidal & Wave Energy
Biogas Energy
Non Conventional Energy Resources
97
Dr. Mandar M. Lele
Energy from Tides and Waves
T ide s a nd Wave s
98
Dr. Mandar M. Lele
Turning Tides into Usable Energy
• Ebb generating system• A dam (barrage) is built
across the mouth of an estuary.
• Sluice gates allow incoming tides to fill the basin.
• As the tide ebbs, the water is forced through a turbine system to generate electricity.
99
Dr. Mandar M. LeleTypes of TurbinesBulb turbine used at La Rance tidal plant on the Brittany coast in
France
100
Dr. Mandar M. LeleTurbines, cont.
Rim turbine used at Annapolis Royal in Nova Scotia
Tubular turbine proposed for use in the Severn tidal project in Great Britain
101
Dr. Mandar M. Lele
Other Possibilities
• Tidal Fences• Completely blocks a
channel so as the tide rises, water is forced through the styles to turn them.
• Can be used between islands or between a mainland and an island as opposed to only across the mouth of a confined bay.
Tides a nd Wave s
102
Dr. Mandar M. Lele
• Tidal Turbines• Only been feasible for
about 5 years• Similar to wind turbines,
they use tidal currents to turn propellers mounted on the seabed to generate power.
103
Dr. Mandar M. Lele
Turning Waves into Usable Energy
• Oscillating water column• Incoming waves force air up
column to turn the turbine• Outgoing waves suck air
down column to turn the turbine
104
Dr. Mandar M. Lele
Tapered Channel System (TAPCHAN)
• Waves feed through tapered channel into reservoir and are then fed through a turbine
• Kinetic energy of the moving wave is changed to potential energy as water is collected in the reservoir
• Concept is similar to that of traditional hydroelectric devices
105
Dr. Mandar M. Lele
Floating Devices(Salter Duck, Clam, Archimedes)
• Salter Duck-Electricity is generated through the movement of the device on the wave (bobbing up and down)
106
Dr. Mandar M. Lele
Wave and Tidal EnergyWhat Can It Be Used For?
The most practical use for tidal energy is for conversion to electricity (similar to hydroelectric dams)
- this is done by creating a dam or barrage, containing several gates and turbines, across an estuary. When there is a difference in water level across the dam, the gates are opened, water flows through the turbines (creating a hydrostatic head), and an electric generator is activated.-generation of electricity peaks and ebbs with the tides each day, so that there is a peak of maximum generation every twelve hours, with no generation at the converse twelve hour mark.
Gilbrat Ratio- ratio of annual energy production in kilowatt hours to length of
barrage in meters. - used to determine cost effectiveness and efficiency of tidal power
site
107
Dr. Mandar M. Lele
Advantages• Renewable • Abundant (estimated that it could produce
16% of worlds energy.)• Pollution free (except during construction)• Relatively consistent (unlike wind that is
inconsistent and is highly concentrated in certain areas depending on the topography.)
• Water is a free resource• Presents no difficulty to migrating aquatic
animals (avoidable)
T ide s a nd Wave s
108
Dr. Mandar M. Lele
Disadvantages• Disturbance/Destruction to marine life (effect
wave climate that effects shallow/shore plant life)
• Expensive to construct (estimated 1.2 billion dollars.)
• Reliability ( have not been around long so we do not know long-term reliability is.)
• Recreational costs (visual impact, sport fishing, swimming, etc.)
• Cost of Maintenance Higher• Power transmission from offshore facilities
harder• Power quality (waves fluctuation)
T ide s a nd Wave s
109
Dr. Mandar M. Lele
Present use of Tidal EnergyTidal power has on a small scale been used through out the history of mankind. It was not until the twentieth century that large scale tidal projects were considered. Today, sites suitable for the utilization of tidal power exist in many places around the world. – France – United Kingdom – Former Soviet Union – Canada – United States
T ide s a nd Wave s
110
Dr. Mandar M. Lele
Present use of Tidal Energy
T ide s a nd Wave s
The extraction of large quantities of tidal
energy is possible however, large scale
tidal power operations are not
technologically or economically feasible
at the present time. Tidal sites are
therefore limited to more modest
developments.
111
Dr. Mandar M. Lele
T her ma l S
ys tems/ S
o lar En er gy
Solar Energy
Wind Energy
Tidal & Wave Energy
Biogas Energy
Non Conventional Energy Resources
112
Dr. Mandar M. Lele
• Biogas is the name applied to a gaseous product released from anaerobic decomposition of different bio-wastes.
• In this process, organic wastes are anaerobically fermented by microorganisms.
Biog as En erg y
113
Dr. Mandar M. Lele
The gas thus produced contains about 60% methane and 40% CO2. Biogas can be produced from cow dung, leaf litter mixtures, animal excreta particularly dairy cattle, pig and sheep etc.
Biog as En erg y
114
Dr. Mandar M. Lele
This is one of the popular treatment methods even for municipal waste, various industrial wastes such as dairy, tannery, fruit processing, pharmaceutical etc.
Biog as En erg y
115
Dr. Mandar M. Lele
Available in unlimited extent.
Very low operation cost.
Very Low maintenance Cost
Totally pollution free.
Advantages of Non Conventional Energy
116
Dr. Mandar M. Lele
High capital costLow output in terms of power and efficiency as compared to conventional sources of energy.Conveyance from one place to other is difficult Conversion from one form to other is difficult Storage is difficult.These energy sources cannot be explored under unfavourable atmospheric conditions such as cloudy environment for producing solar energy or very calm days for producing wind energy etc.
Disadvantages of Non Conventional Energy
117
Dr. Mandar M. Lele
Impact of Harnessing Various Sources
OfEnergy on Environment
118
Dr. Mandar M. Lele
• As discussed, it is clear that, particularly in case of conventional energy sources, lot of burden is put on the environment.
• With rapid industrialization and population explosion, demand for these sources of energy is ever increasing.
• These energy sources are used to run the industries, vehicles and for generating power.
• This ultimately leads to degradation of environment, air, water, land and noise pollution.
• Hence there is a need for harnessing the energy.
Impact of Harnessing Various Sources Of
Energy on Environment
119
Dr. Mandar M. Lele
Due to rapid urbanisation and industrialisation, the dependency for energy is ever increasing. But the availability of energy in India is far less than the demand. Hence there is a need to harness the energy resources. Wherever possible, the emphasis shall be given on using the renewable energy sources.
Need for Harnessing Energy Sources
120
Dr. Mandar M. Lele
To promote the use of such sources, some corporations and civic authorities have implemented some schemes such as tax rebate for those who adopt such sources. The central government also provides subsidy to some projects such as use of solar water heaters, wind mills etc.
Need for Harnessing Energy Sources
121
Dr. Mandar M. Lele
Need for Harnessing Energy Sources
It shall be noted that although non-conventional energy sources are the best alternatives for fulfilling our need for energy and at the same time to prevent the environmental degradation, these sources have some limitations such as high initial cost, low output efficiency as compared to conventional sources of energy, difficulties in storage and transmission etc. Hence an integral approach to connect the non-conventional sources with conventional sources in the form of harnessing the energy shall be adopted.
122
Dr. Mandar M. Lele
There are many sugar industries in India
including Maharashtra, who have started
their own co-generation power plants.
The sugar waste bagasse, (which is a dry
left out of sugarcane) is used as fuel in
boiler from which steam is generated and
further turbines could be run to produce
electricity.
Need for Harnessing Energy Sources
123
Dr. Mandar M. Lele
Ethanol which is a by-product manufactured from the sugar waste molasses, is mixed with petrol to the extent of @ 10% by volume, resulting in huge saving in foreign exchange for the country.
Apart from this in some instances, the organic waste in the form of solid waste generated from the community is used to produce electricity or even at household level, the kitchen waste or the human excreta is used to produce biogas.
Need for Harnessing Energy Sources
124
Dr. Mandar M. Lele
Need for Harnessing Energy SourcesAlthough the percentage of population
utilising these non-conventional energy sources is very poor at present, with the advancement of technology and spread of awareness amongst the common people to use such alternative energy sources, the dependency on conventional sources of energy will reduce.
This will help the human population across the globe and will help to reduce main critical global issues such as global warming, climate change etc.
125
Dr. Mandar M. Lele
Need for Harnessing Energy Sources
As mentioned above, the use
of conventional energy
sources in uncontrolled
manner creates all sorts of
pollution of the environment.