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Conventional

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Non Conventional

Energy ResourcesPart- 1

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a)Types of energy:- conventional and

non-conventional.

b)Need for harnessing alternative

energies to meet the increased

demand.

c) Methods of harnessing energies.

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Fuels & CombustionFuels & Combustion

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Introduction

Type of fuels

Performance evaluation

Energy efficiency opportunities

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Energy ConversionEnergy Conversion

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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

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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

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Introduction

Type of fuels



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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)

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Liquid FuelsDensity• Ratio of the fuel’s mass to its volume at 15 oC,

• kg/m3

• Useful for determining fuel quantity and quality

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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

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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.)

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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

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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

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Liquid FuelsCalorific value• Heat or energy produced

• Gross calorific value (GCV): vapour is fully condensed

• Net calorific value (NCV): water is not fully condensed

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Fuel Oil Gross Calorific Value (kCal/kg)Kerosene 11,100Diesel Oil 10,800L.D.O 10,700Furnace Oil 10,500LSHS 10,600

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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

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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

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Liquid FuelsStorage of fuels• Store in cylindrical tanks above or below

the ground

• Recommended storage: >10 days of normal consumption

• Cleaning at regular intervals

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Liquid FuelsT her ma l S

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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.)

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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

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Solid Fuels

Physical properties• Heating or calorific value (GCV)

• Moisture content

• Volatile matter

• Ash

Chemical properties• Chemical constituents: carbon, hydrogen,

oxygen, sulphur

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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

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Solid Fuels (Physical properties)T her ma l S

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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

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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

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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

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Solid Fuels (Physical properties)Proximate analysis

Typical proximate analysis of various coals (%)

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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

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Solid Fuels (Chemical Properties)Ultimate analysis

Typical ultimate analysis of coal (%)

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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

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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

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Gaseous FuelsAdvantages of gaseous fuels• Least amount of handling

• Simplest burners systems

• Burner systems require least maintenance

• Environmental benefits: lowest GHG and other emissions

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Gaseous FuelsClassification of gaseous fuels

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(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

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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

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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

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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

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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

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Comparing FuelsT her ma l S

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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 -

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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.)

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Calorific value of fuels

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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.

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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.

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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

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= (m+9H2) kg



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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.

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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.

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Introduction

Type of fuels



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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

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• 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

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1T) Temperature

2T) Turbulence

3T) Time

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Oxygen is the key to combustion

Principle of CombustionT her ma l S

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Bureau of Energy Efficiency, India, 2004

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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

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• Measure CO2 in flue gases to estimate excess air level and stack losses

Concept of Excess AirT her ma l S

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Carbon dioxide (%)

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Source: Bureau of Energy Efficiency, India, 2004

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Concept of Excess AirT her ma l S

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Residual oxygen (%)

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Bureau of Energy Efficiency, India, 2004

• Measure O2 in flue gases to estimate excess air level and stack losses

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Introduction

Type of fuels



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Preheating of combustion oil

Temperature control of combustion oil

Preparation of solid fuels

Combustion controls

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Energy Efficiency OpportunitiesEnergy Efficiency Opportunities

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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


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To prevent overheating• With reduced or stopped oil flow

• Especially electric heaters

Using thermostats

Temperature Control of Combustion Oil


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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


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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



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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



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• 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

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Non Conventional Energy Resources

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Solar Energy

Wind Energy

Tidal & Wave Energy

Biogas Energy


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Solar Energy

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What is Solar Energy?• Originates with

the thermonuclear fusion reactions occurring in the sun.

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•Represents the entire electromagnetic radiation (visible light, infrared, ultraviolet, x-rays, and radio waves).

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How much solar energy?

The surface receives about 47% of the total solar energy that reaches the Earth. Only this amount is usable.

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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!

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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.

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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.

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• The water circulates throughout the closed system due to convection currents.

• Tanks of hot water are used as storage.

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Heating Water: Active System

Active System uses antifreeze so that the liquid does not freeze if outside temp. drops below freezing.

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Heating Living Spaces

Passive Solar

Trombe Wall

Passively heated home in Colorado

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• 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

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Power Towers

Power tower in Barstow, California.

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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.

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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.

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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.

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Solar Energy

Wind Energy

Tidal & Wave Energy

Biogas Energy


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Wind Energy

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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?

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Wind Energy Through the Years

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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?

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• 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?

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• 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?

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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

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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.

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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.

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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.

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Case Study

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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

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• 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

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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.

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T her ma l S

ys tems/ S

o lar En er gy

Solar Energy

Wind Energy

Tidal & Wave Energy

Biogas Energy


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Energy from Tides and Waves

T ide s a nd Wave s

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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.

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Dr. Mandar M. LeleTypes of TurbinesBulb turbine used at La Rance tidal plant on the Brittany coast in

France

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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

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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

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• 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.

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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

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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

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Floating Devices(Salter Duck, Clam, Archimedes)

• Salter Duck-Electricity is generated through the movement of the device on the wave (bobbing up and down)

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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

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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

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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)

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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

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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.

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T her ma l S

ys tems/ S

o lar En er gy

Solar Energy

Wind Energy

Tidal & Wave Energy

Biogas Energy


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• 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

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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

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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

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Available in unlimited extent.

Very low operation cost.

Very Low maintenance Cost

Totally pollution free.

Advantages of Non Conventional Energy

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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

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Impact of Harnessing Various Sources

OfEnergy on Environment

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• 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

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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

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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.


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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.

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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.


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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.


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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.

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As mentioned above, the use

of conventional energy

sources in uncontrolled

manner creates all sorts of

pollution of the environment.

renew energy 1

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