ENERGY CONSERVATION NECESSITY & ITS · PDF file137 Puneet Chawla, Heena Garg , Rajni Bala...

International Journal of Engineering Technology, Management and Applied Sciences

www.ijetmas.com December 2014, Volume 2 Issue 7, ISSN 2349-4476

135 Puneet Chawla, Heena Garg , Rajni Bala

ENERGY CONSERVATION – NECESSITY & ITS SCOPE

Puneet Chawla

1, Heena Garg

2 & Rajni Bala

3

1. A. P. in Electrical Engg., Ch. Devi Lal State Institute of Engg. & Tech., Panniwala Mota (Sirsa)

2. Lecturer in Electrical Engg., Ch. Devi Lal State Institute of Engg. & Tech., Panniwala Mota(Sirsa)

3. Lecturer in Electrical Engg., Ch. Devi Lal State Institute of Engg. & Tech., Panniwala Mota(Sirsa)

ABSTRACT: Today, the development of any country depends on a great extent on the availability

and usage of energy. It is therefore natural that we all would be utilizing the available energy for

industrial production, commercial activities, urban & rural development and personal requirements.

No country can therefore afford to think of not using the energy. The vast bulk of the energy used on

the world today is in the form of non-renewable oil, natural gas and coal. These resources were laid

down many millions of years ago and are at present being consumed at the rate of 9 billion tones of

coal equivalent to 0.32 million pentajoules per annum. This compares with proved recoverable

energy resources of 20.3 million pentajoules of coal and 11.2 pentajoules of oil and natural gas. So,

we must conserve the energy by all possible means as a bounden duty to those who come after use.

Use of energy efficient equipment and equipments of correct size, refurbishing of products in

operation, switching off the electricity when not needed are some of the simple methods which saves

energy. Educating people, particularly the general public about the methods of saving and

possibilities of spending less on the energy usage would go a long way in reducing energy

requirements. Conservation of energy is becoming a vital issue not only because of the tremendous

gap between demand and supply of energy. Conservation of electrical energy means the reduction

in energy consumption but without making any sacrifice of quantity and quality of production.

This paper describes about the concepts of energy conservation and the various methods by which

the energy conservation may be achieved.

Keywords: Energy Conservation, Energy Efficiency, Re-equipping, Power Generation Sector,

Energy Conservation Act, 2003, Utility Fossil Based power generation sector, Ultra

super-critical technology, Integrated gasification combined cycle (IGCC), Industrial co-generation,

renewable power generation, Gas Insulated Substation, HVDC transmission, FACTS transmission,

Distributed generation, High Temperature superconducting (HTS) DC cables.

INTRODUCTION:

ENERGY CONSERVATION:

1. Conservation of electrical energy means the reduction in energy consumption but without making

any sacrifice of quantity & quality of production1.In other words, for the same energy consumption,

higher production, it does not prevent you use of energy by fixing some limit quantitatively within

the agreement but insists for use efficiently thus decreasing the cost of production to some extent by

the way of reduction in the energy bill.

2. It can also be defined as the substitution of energy with capital, labour, material & time.

This definition also covers the substitution of scarce type of energy (e.g. oil) with abundant type of

energy (e.g. coal) or the substitution of energy with convenience.

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PRINCIPLES OF ENERGY CONSERVATION: Two principles governing energy conservation

policies are maximum thermodynamics efficiency and maximum cost effectiveness in energy use.

The first and second law of thermodynamics measure the efficiency of energy use, allocation of

available production factors determine the cost effectiveness of conservation. Maximum

thermodynamics efficiency in energy use is defined as maximum work production by using a given

amount of primary energy input.

Maximum Work= (Energy input)–(energy loss in transfer)–(energy discharge).

ENERGY CONSERVATION APPROACH: Conservation of energy is using more efficiently by

substituting time, convenience, labour and capital for effective optimization of costs. Energy today

has become an indispensible component of industrial production, agriculture, employment &

economic growth. Natural gas & oil are dominant in energy use and their shortages have caused

economic chaos in the present and in the recent past. Energy available for the future focuses a lot of

attention on the use of energy efficient equipment, adoption of energy conservation techniques &

switching over to new energy technologies.

STEPS TOWARDS ENERGY CONSERVATION REQUIRE 3 LEVELS OF EFFORTS2: The

3 level of efforts are required for energy conservation in time:-

a) Formulation of administrative & information programme relatively easy & in expensive to

implement like tune ups, light turn offs, small adjustment in production processes etc, effective in

reducing current energy consumption to the extent of 3% to 7%.

b) Re-equipping, Retrofitting and Re-cycling through the small incremental investments for gaining

10% savings.

c) Major production process changes through the large scale capital expenditure for obtaining the

saving from 20% to 90% gain, depending upon the nature of operations and facilities involved.

WHY ENERGY CONSERVATION?

Energy is a scarce commodity. Energy in any form is a scarce commodity & an inexpensive

resource. However, if look at the predicted future human population fugues & consider the

probability that the individual life expectations will increase, we see that energy could be in future is

in short supply.

POWER POLICIES ON 11TH

AGENDA: The 11th

five-year plan contains several policy measures

for power sector. Power secretary has examined legislative & policy issues and use of inputs for

sector. This group has constituted into eight sub-groups on demand projection, generation, planning,

transmission planning & distribution including villages & house-hold electrification, legislative &

policy issue formulation, energy efficiency & conservation.

Energy savings can be begun at home. Energy rating similar to those produced for fridge and

washing machines will have to be produced for every home brought and sold in UK. Certificates

prepared by registered home inspectors will give houses A to G ratings for every emission.

They will also tell home owners, the current average costs of heating, hot water & lighting in their

home and suggest how to reduce them.

ENERGY CONSERVATION V/s ENERGY EFFICIENCY3:

The policy, goals and concepts will have to be shifted from “Energy Conservation” to “Energy

Efficiency” and from “Energy Inputs” to the “Effectiveness of energy use” and “Effective Services”.

So, conservation of energy is achieved when the growth of energy is reduced, measured in terms of





physical terms. So, Energy Conservation can be the result of several processes or developments such

as productivity increase or technological progresses.

Energy efficiency is often viewed as a resource option like coal, oil & natural gas. It provided

additional economic value by preserving the resource base and reducing pollution e.g. replacing

traditional light bulb with CFLs and now LED lamps means you will see the 1/4th

of the energy to

light a room.

ENERGY CONSERVATION OBJECTIVES: Broadly energy conservation program initiated at

micro or macro level will have the following objectives:-

a) To reduce imports of energy & reduce the drain on foreign exchange.

b) To improve exports & manufactured goods or of energy or both.

c) To reduce the environmental pollution per unit of industrial output as carbon dioxide, smoke,

sulphur dioxide, dust or coal mine discard etc.

d) Thus reducing the costs that pollution incurs either directly as damage or as needing special

measures to combat it once the pollutants are produced.

e) Generally to relieve shortage & improve development.

HOW TO ACHIEVE OBJECTIVE OF ENERGY CONSERVATION4: A three prolonged

energy conservation strategy is drawn up:-

Short Term Measures: (Potential savings of 5% to 10%)

1. Meeting operational improvements requiring negligible capital investments.

2. Improved fuel storage, handling & preparation practices.

3. Insulation of steam lines & pipes.

4. Housekeeping & scheduling of process equipment.

5. Minimizing radiation losses through opening.

6. Improved load factor.

Medium Term Measures: (Potential savings of 15% to 20%)

1. Waste heat recovery devices and modifications & design of equipment, needing moderate capital

investment.

2. Installations of waste heat recovery devices.

3. Reducing wall losses in the furnaces with better insulating materials.

4. Instrumentation of furnace & process house.

5. Power factor improvements.

6. Optimization.

Long Term Measures: (Potential saving of 20% to 25%)

1. Fuel substitution, modernization of equipment, process as well as utilizes, capital intensive heat

recovery devices with payback period of 5 to 6 years.

2. Replacement of old inefficient boilers/ equipments.

3. Substitutions of fuel oil to coal in boilers and other equipment.

4. Modernization of drives.

5. Standardization.

6. Use of correct size of motors.

7. Optimization.

Total savings through all measures= 20% to 30%.

Energy Conservation in the energy demand management that aims at increasing the efficiency of use.

An “energy audit” helps to understand more about the ways, the different energy sources are used in





the industry and helps to identify the areas where waste can occur and where the scope of

improvement may be possible. The energy audit would give a positive orientation to the energy cost

reduction, preventing maintenance and quality control programmes.

ENERGY CONSERVATION IN THE POWER GENERATION SECTOR5:

Indian power generating sector is showing a gradual shift from public owned generators to private

owned generators. Self-financed power generators, Independent Power Producers (IPPs) are playing

an important role in shaping the power development. Short term demand os handed through

Merchant power plant (MPPs) who are growing from 3GW presently to 25GW by 2015. Majority of

their MPPs operate under hybrid mode (short term as well as long term). There is also a transition in

sourcing of power generating equipment from public owned players to private owned players based

on capital cost economics a transition from simple conventional capacity addition to energy efficient

technologies is also evident.

The energy efficient effort on the supply side should be addressed in the back drop of resolution of

the outstanding long term problems in power generating sectors such as:-

- Inadequate generation capacity.

- High auxiliary power in power stations.

- Low efficiency of generating plants.

- Ageing performance deterioration of old plants.

- High ash content in Indian coal leading of problems of disposal, pollution and erosion of plant

components.

- High silt burden in the Himalayan Rivers leading to severe erosion of hydro turbines.

The Energy Conservation Act 2001, Electricity Act, 2003 and Electricity Policy 2005 are some of

the effective mechanisms for transformation of performance of the Indian power sector. Guidelines

for directing the resources and efforts towards energy efficiency programs, directional shifts to

power development pathways etc. have been possible with the help National Action Plan on Climate

Change (NAPCC), 2008. The National Mission on Energy Efficiency 2009 (NMEE) and National

Solar Energy Mission, 2009 have developed by Govt. of India for development of power sector.

UTILITY FOSSIL BASED POWER GENERATION SECTOR: There are two basic routes for

increasing the operating capacity & efficiency of power generation:-

Re-vitalizing the existing plants such that they give high efficiency, better load plant factors and

higher availability factors through-

- Immediate Measures- Tuning of the system & operational optimization.

- Simple Measures- Planned maintenance of the equipment during annual and capital periods.

- Medium Term Measures- Renovation & modernization through replacement/ retrofitting/ upgrades

of equipments.

- Installing new generating capacity (long term measures) either through green field or expansion

projects.

Some of technology options are described below:-

1. Revitalizing in-service plants through E-R & M:- R & M and life extension programs offer an

opportunity to introduce the benefits of new and modern technology in ageing units & restore their

energy efficiency (hence E-R & M in short). This been a successful process since the last 25 years.

The thrust of E-R & M and LE programs have been to restoration of the unit capacity to its original

rated capacity and improve the plant load factor by at least 10 percentage points. Besides this,

restoration of energy efficiency is also a goal in this program. The national average plant load factor

(PLF) for coal fired plants has been registering a continuous improvement from 70% in 2001 to 80%





at present. Fig. (a) & (b) shows the number of units taken up for E-R & M & LE and total capacity

during 7th

to 11th

Five year plan periods. Fig (c) shows the capital expenditure for taken up E-R & M

and LE.

(a) (b)

(c)

Fig (d) and (e) shows about the state-of-the-art efficiencies of utility boilers and of overall power

generating units for various types of fuels.

(d) (e)

Another method to achieve the energy efficiency is High Efficiency processes- Ultra super critical

technology6. The word critical in thermal plants must not be confused with the nuclear plants going

critical in which context it applies the chain reactions have become sustainable. In fact the word

super-critical in the nuclear context implies that the chain reactions are uncontrollable. Nuclear

plants are operating with Steam plant at sub-critical pressures and temperatures far below the fuel

fired reactors and the Rankine cycles because of safety requirements through-out the process,

efficiency may be lower.

The standard working fluid in the Rankine power generating cycle is water-steam. When the main

steam parameters exceed the critical point of water, 22.09 MPa & 374.140C, the operating regime is

called as super critical regime. Operation below there limits are called sub-critical regime on

pressure 13.0 MPa and 5400C. Plants with operating steam cycle parameters of 31.0-34.5 MPa &

5660C (main steam/ 1

st reheat/ 2

nd reheat) are generally referred as ultra-critical steam regime. This

improves the gross plant overall efficiency as high as 44-45%, better load response, low level of

water requirements, reduced carbon emissions and economic life of 25 years. The present ultra-

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Gorss overall effieciency (%)





critical temperature used in the rankine power generation cycles are 5660C and the upcoming

temperature is in progress is of 700+0C. Fig. (f) & (g) gives a comparison of ultra-supercritical cycle

with sub-critical and super-critical cycles.

(f) (g) So, in the context of ultra-super critical regime, the massive efficiency improvements coupled with

new cost reduction material concepts renders, ultra-supercritical units of 600MW or 800MW as ideal

technology for Indian capacity addition. These may be installed at add-on units in the existing plants

or set up the new plants on new sites. Most new plants are preferring the super-critical or ultra-

supercritical power cycles. However, the ultra-supercritical units use pulverized fuel combustion

systems in the present design and hence called as ultra super-critical with pulverized combustion

(USCPC).

Integrated gasification combined cycle (IGCC): The IGCC involves three technologies- coal

gasification in a gasifier, cleaning and processing in heat exchangers and cleaning trains. Steam-gas

(Syngas) conversion through a gas turbine-generator for 66% of power output and steam turbine-

generator for balance 34% power output. IGCC technology is proven for cleaner fuels like natural

gas and LPG. IGCC provides high efficiency of 57-58% as compared to 35% efficiency of steam

generating power plants. The IGCC is superior to USCPC in terms of gross and net overall

efficiencies as well as emission indices, as IGCC = 56.47% and of USCPC = 52.80%.

Alternative Fuels- Gas based generation- a transition towards a hydrogen economy:- Natural

gas is rich in hydrogen- an intermediate between rich coal and clean fuel- hydrogen. The

environmental impacts of gas based plants are minimal. A global rebirth of gas based generation for

rapid capacity addition through combined power plants- gas turbines integrated to waste heat

recovery boiler (steam turbine) is emerging. Gas is available in Gujarat, in Krishna-Godavari basin in

Andhra Pradesh & in Maharashtra. Combined cycle plants (gas turbines with steam power plants)

offer efficiency as high as 55-58% with 10-11% cost of gas and generation cost is low.

Gas turbines are popular because of their rapid start up time (5-15 min. from a cold start), high

availability (>95%), low net auxiliary power (< 2%), low compressor power (< 15%) and high

efficiency (> 30%). Fuel wise gas turbine technologies are applicable as: LNG, re-gasified LNG (R-

LNG), CNG, naphtha, diesel. The environmental impact of gas based plants are minimal (SPM less

than 25ppm) as the combined cycle efficiencies are +60% and heat rate are superior to 1434

kcal/kWh. But the focus in gas turbines is enhancement of the life of blades and associated

components. The life of blades in gas turbines is 25kh as compared to 300kh to steam turbine blades

& the compressor blades is presently resulting in high O&M costs , thus major replacement of

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Super Critical cycles

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Gross Unit heat rate (kcal/KWh)





turbine internal components mostly blades. Fig. (h) gives the capital costs of each type of power

plant.

(h)

BY-PRODUCT POWER GENERATION:

Industrial co-generation: The captive power plant (CPP) sector size is ~25GW of which combined

heat and power sector (CHP) is ~10GW. The CHP has PLFs of 30% to 70%, which are not

comparable with utility plants of PLF 80%. This is because of seasonal nature and demand based

production and also the consideration that power is a by-product and not the only end goal. However,

they are preferred because of their low carbon contents and low specific pollutant generation rates.

Bagasse based co-generation form sugar mills: Cane based sugar sector is the second largest agro

industry in India after cotton with over 700 sugar mills catering to 3.0 million tonnes of sugar. Sugar

based CHP is identified as a renewable cogenerating utilities. The present national capacity of sugar

based CHP is 1.6GW and national potential is 7GW. Bagesse are seasonal plants because the number

of crushing days range from 160-210 days/ year with a national average of 125 days/ year. The PLF

varies from 45-60% and it is feasible for plants to be operated at PLFs of 80+% through the

minimization of internal steam demand. The best possible power generation is as high as 170kWh/t

of cane crushed. This leaves 146 kWh/t of cane crushed to exports.

Cogeneration from other biomass: After bagesse rice husk is considered as the next largest source

of convertible biomass. The 170 million tonnes of paddy biomass produces around 20-30 million

tonnes of usable husk which produces around 3GW of power. The long term potential of agricultural

residual based biomass generation is 18GW.

RENEWBLE POWER GENERATION:

Hydro power: Hydro (installed capacity of 39GW) with a potential of 150GW is a mature

technology with multiple run of the river underground power projects across the same river. Under

the 12th

Plan, around 10GW of hydro is proposed to be installed in the country. The world potential

for hydro is 5TW. Pumped storage power plants will have to be installed for handling the peaking

power due to sudden loss of power plants. The pumped storage power plant can be sized from

150MW to 2GW. Small hydro potential is around 15GW. The energy efficiency of hydro power

plant is 50-85% depending upon the weather conditions and whether the conversion is through

Pelton wheels, Francis or Banki turbines and speed of the turbo-generator..

Wind based generation: Wind based generation with a world capacity of 242GW in end of 2011

and India is 5th largest wind power producers with a capacity of 15GW with a PLF of 20-21%. The

states of Tamil Nadu, Maharashtra and Karnataka are accounting for nearly two thirds of countries

renewable generation.

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Capital cost in Rs. /MW





Solar Photovoltaic (SPV) based generation: The present world production of solar PV of all types

is 11GW /year. By 2050, 30% of the world energy is to be produced from the renewable energy. The

major countries adopted solar PV in order of their capacities addition are Germany, Spain, Japan and

USA. In earlier years, solar PV was used on micro scale of 10W to 1kW for portable systems or

onsite applications. In earlier years, solar PV was used on micro scale of 10W to 1kW for portable

systems or onsite applications. Present day, use is as follows:-

- Utility power (grid) scale: 1 to 20MW.

- Industry (captive scale): 200kW to 1MW.

- Domestic & micro-commercial (captive or grid connected): 1 kW to 10kW.

Grid connected utility solar PV plants are the solution for large capacity generations. The present

capacity in India is 12MW and is targets to 1.3GW in near future.

Integration of Solar PV and Wind technology at the tail end of the grid would require smart grid

configuration for load balancing. Presently, Rajasthan is leading in the solar PV capacity addition

and plans to install 10-12GW of solar power through both solar PV and solar thermal routes.

NUCLEAR POWER- A LONG TERM RENEWABLE GENERATION OPTION: Nuclear

generation (installed capacity of 4.78GW) is also a mature technology has been a victim of resistance

from many sides. The presently estimated uranium reserves will be able to supply around 15GW in

pressurized heavy water reactors (PHWRs). The fuel can be processed with plutonium and the

residual uranium has a power potential in the fast breeder technology, based on plutonium-uranium

cycle. The world potential for nuclear power through fast breeder reactors is 5TW. The first Indian

fast breeder reactor was installed in 1985 using plutonium-uranium cycle and the approximate cost of

reactors is Rs. 7-8 Cr./MW.

ENERGY CONSERVATION IN POWER TRANSMISSION & DISTRIBUTION SECTOR7:

The energy conservation in the sector of Transmission and distribution of electric power is also as

important as that in the generation and in domestic sectors. This is covered by the following methods

adopted for the energy conservation:

1. Flexible AC Transmission System

2. High Voltage DC Transmission

3. Distributed Generation in distribution

4. Gas Insulated Sub-stations.

5. Superconductors HTS cables

6. Wide Area monitoring systems.

1. Flexible AC Transmission System (FACTS): A flexible alternating current transmission system

(FACTS) is a system composed of static equipment used for the AC transmission of electrical

energy. It is meant to enhance controllability and increase power transfer capability of the network. It

is generally a power-electronic based system.

FACTS is defined by IEEE as a power electronic based system and other static equipment that

provide control of one or more AC transmission system parameters to enhance the power transfer

capability/

The first FACTS installation was at the C.J. Slatt Substation in Northern region. This is a 500kV, 3-

phase, 60Hz substation and was developed by EPRI, the Bonneville Power Administration and

General Electric Company. In FACTS transmission system, the effective transmission is achieved by

series compensation and shunt compensation devices obtained by series capacitors and shunt





capacitors for voltage compensation and current compensation due to line inductances and load

inductance respectively for long transmission lines.

Series Compensation: In series compensation, the FACTS is connected in series with the power

system. It works as a controllable voltage source. Series inductance exists in all AC transmission

lines. On long lines, when a large current flows, it causes a large voltage drop. To compensate, series

capacitors are connected, decreasing the effect of the line inductance.

Shunt Compensation: In shunt compensation, power system is connected in shunt (parallel) with

the FACTS. It works as a controllable current source. Shunt compensation is of two types:-Shunt

capacitive compensation: This method is used to improve the power factor of the lines. Whenever

the inductive load is connected to the transmission lines, the power factor lags. To compensate a

shunt capacitor is connected which draws current leading the source voltage. The net result is

improvement in power factor.

Shunt Inductive compensation: This method is used when charging the transmission line, or, when

there is very low load at the receiving end. Due to very low or no load- very low current flows

through the transmission line. Shunt capacitance in the transmission line causes voltage

amplification. The receiving end voltage may become double to sending end voltage.

The power transfer capability is thereby increased depending upon the power equation,

P= (E x V / X) (sin δ)

2. High Voltage Direct Current (HVDC) Transmission System: A high voltage direct current

(HVDC) electric power transmission system used direct current for the bulk transmission of electric

power, in contrast with the more common alternating current (AC) systems. For long distance

transmission, HVDC systems may be less expensive and suffer lower electrical losses. For

underwater power cables, HVDC avoids the heavy currents required to charge and discharge the

cable capacitance during each cycles. For shorter distance, the higher cost of HVDC conversion

equipment compared to an AC system may still be warranted, due to other benefits of direct current

links.

The modern form of HVDC transmission used the technology developed extensively in the 1930sin

Sweden (ASEA) and in Germany. Early commercial installations included one in the Soviet Union in

1951 between Moscow and Kashira and a 100KV, 20MW system between Gotland and mainland

Sweden in 1954. The longest HVDC link in the world is currently the Xiangjiaba-Shanghai 2,071km,

±800kV. Early in 2013, the longest HVDC link will be the Rio Madeira link in Brazil, which consists

of two bipoles of ±600kV, 3150 MW each, connecting Porto Velho in the state of Rondonia to the

Sao Paulo area, where the length of the line is 2,375km.

Practical conversion of power between AC and DC became possible with the development of

power electronics devices such as mercury-arc valves and starting in the 1970s, semiconductor

devices such as thyristors, IGBTs, MCTs and IGBTs.

Advantages of HVDC transmission:

1. End point-to-end point long-haul bulk power transmission without intermediate “taps”, usually to

connect a remote generating plant to the main grid for example, the Nelson River DC Transmission

system in Canada.

2. Increasing the capacity of an existing power grid in situations where additional wires are difficult

or expensive to install.

3. Power transmission and stabilization between unsynchronized AC networks, with the extreme

examples being an ability to transfer the power between the counties that use AC at different





frequencies. Since such transfer can occur in either directions, it increase the stability of both

networks by allowing them to draw on each other in emergencies and failure.

4. Stabilizing a predominantly AC power grid, without increasing fault levels.

5. Undersea cables transmission schemes e.g. 250km Batlic Cables between Germany and Sweden,

580km NorNed cable between Norway and the Netherlands. And 290km Basslink between the

Australian mainland and the Tasmania.

6. Controllability 7. Environmental concerns

8.

To disadvantages of HVDC, we can include conversion, switching and control. Static converters are

expensive. In short distances losses in static inverter may be even bigger than in AC transmission. In

the future static converters will be replaced by thyristors. However, less reliable and has lower

availability than AC systems.

Costs of HVDC Transmission: Generally, providers of HVDC systems, such as Alston, Siemens

and ABB do not specify cost details of particular projects. However, some practitioners have

provided some information such as:

For an 8GW 40km link laid under the English channel, approximate primary equipment costs for

2000MW, 500kV bipolar HVDC link is: Converter station: 173.7M USD and subsea cable: 1.6M

USD/km. In April 2010, for 2000MW, 64km line between Spain and France is estimated at EUR 700

million. Today HVDC is very important issue in transmission energy. In near future this technology probably

will be developed very intensive. Influence on future may have intensive spread of renewable energy

source, also wind farm which need undersea connections. Also problem of cascade blackout can be

reduced by application of HVDC. Intensive, very large investments in e.g in China and India show

that high-voltage direct current will very important in the future, especially in big, new-industries

countries.

3. Gas Insulated Sub-stations9: The increasing demand of electrical power in cities and industrial

centres requires the installation of compact and efficient distribution and transmission networks.

High voltage gas-insulated substations (GIS) are ideal for such applications.

The F35 GIS is 3-Ø, SF6 gas insulated high voltage metal enclosed substation designed for indoor and

outdoor installations. The reliable operation of F35 GIS is the result of field proven design provides a

mechanical operating mechanism, upto date computer aided design methods and comprehensive

development & testing. F35 switchgear is completely adoptable to layouts used in modern electrical

substations. The arrangement is suitable for future extension or modification of the equipment. It

enables new, original and effective solutions, while preserving the necessary operating security and

maintenance criteria.

Advantages of compact GIS:

1. Flexibility

2. Space saving, high compactness.

3. Increased safety and reliability

4. Modularity and adaptability

5. Easier operation

6. Accessibility of components.





Top quality manufacturing and rigorous inspection guarantee excellent performance. The mechanical

drives are simple, contain few moving parts, gas tightness container, cast/sheet aluminium enclosures

optimised dielectric performance, aluminium alloys for superior resistance to corrosion, synthetic

elastomeric gasket sealing with minimum maintenance.

GIS Components: Main components equipped into the GIS substations are:-

Circuit breaker.

Combined Circuit breaker and disconnector.

Combined 3-position disconnector/ earthing switch.

Make-proof earthing switch.

High Voltage interfaces:- F35 type switchgear can be directly connected to high voltage cables,

transformers, or overhead lines by use of interfaces such as plug-in dry type cable connection, gas

insulated busducts in case of transformers, busducts and SF6 air bushings in case of overhead lines.

Customised Instrument Transformers.

Local Control: Local control is integrated into the switchgear. The local control of each bay

provides the following functions: Control and monitoring of the bays and density of the SF6 gas

inside the compartments, electrical interlocking between components, interface the remote control,

local control and the GIS equipment.

Applications of GIS Substations: For power transmission & distribution, the major applications

are:

Single busbar layout of 72.5kV

Double busbar layout of 145kV

Double busbar layout of 170kV 4. High Temperature Superconducting (HTS) DC cables

10: HTS DC cable is a large-capacity,

compact, energy-saving & environmentally-friendly cable. Moreover, further improvements in

performance & declines in price are likely to give rise to greater economic efficiency. High-

temperature superconducting (HTS) cable, characterized by high current density and low

transmission loss, shows promise as a compact large-capacity power cable that exhibits several

environmental advantages such as energy and resource conservations as well as no external

electromagnetic fields, nonexplosiveness, nonflammability and nontoxicity. Due to these advantages,

HTS AC cable demonstration projects are being planned and promoted.

The zero resistance of HTS material is observed only in DC current, while the transmission loss is

generated in AC current. Moreover, it is necessary to take measures to solve the problems to HTS

AC cables such as protection against short circuit current and solution to avoid unbalanced AC

current in each HTS conductor. HTS DC cable, on the other hand, is a cable that utilizes the

advantages of superconductivity most effectively and shows no problem inherent in HTS AC cables.

Advantages of HTS DC cables: 1. No conductor loss: Since the direct current resistance of HTS DC

cable is zero, there is no conduction loss, transmission capacity of cable can be increased without

limits by number of cables of HTS wires that constitute a cable.

2. In addition, the required cooling capacity per unit length can be reduced because the only potential

source of loss in HTS DC cable is heat invasion due to thermal insulation.

3. EMI free- Electromagnetic Induction free in HTS DC cable by flowing the return current through

the shielding layer in monopolar transmissions.

4. Superiority in Electrical Insulation design due to no thermal gradient occurred in it.





HTS DC cable applications: In view of the above advantages and superiority of HTS DC cable, the

major applications can be as under:-

1. Ultra-high substations.

2. Primary substations.

3. Relay substations.

4. Distribution substations.

5. From back-to-back to interconnection applications and other applications.

5. Distributed Generation in the distribution: A key aspect of electricity supply quality in a power

system in the optimum application of voltage levels to all transmission and distribution networks.

With significant penetration of distributed generation, the distribution network has become an active

system with power flows and voltages determined by the generation as well as loads. Distributed

generation, defined as small scale (1KW- 50MW) electricity generation, is fairly new concept in

economic literature about electricity market. DG (Distributed generation) was the first power plants

only supplied electricity to consumers to the close neighbourhood of the generation plant. The first

grids were DC based and so, supply voltage was limited, as was the distance that could be used

between generator and consumer. Balancing demand and supply partially done with local storage,

batteries which could be directly coupled to DC grid.

Distribution generation is a back-up electric power generation unit that is used in many industrial

facilities, hospitals, campuses, commercial buildings etc. Most of the back-up units are used to

provide emergency power during the time when the grid connected power is unavailable.

DG includes induction and synchronous generators, as well as any type of electrical inverter capable

of producing AC power. So, DG includes synchronous generators, induction generators, combustion

gas turbine, fuel cells, solar photo voltaic and wind turbine etc.

DG is becoming increasingly popular due to their low emissions, low noise levels & high efficiency.

One of the main advantages of DG is their close proximity to the customer loads. DG can play an

important role in improving reliability of current grid, reducing losses, providing voltage support and

improving power quality.

DG defined as small scale electricity generation. “DG as all generation units with a maximum

capacity of 50MW to 100MW, that are usually connected to distribution network and that are neither

centrally planned nor dispatched.” Ackermann et al (2001)11

have defined DG in terms of connection

& location rather than in terms of generation. He defines, “DG sources as an electric power

generation connected directly to the distribution network for its energy conservation approach. The

table below listing the different technologies used for distributed generation:- Technology Capability Utility integration

Solar PV A few W to several 100KW DC to AC converter

Wind A few 100W to few MW Asynchronous generator

I.C. Engine A few 100KW to tens of MW Syn. Generator/AC to AC converter

Combine

cycle

A few MW to several 100MW Synchronous generator

Micro

Turbine

A few tens of KW to few MW AC to AC converter

Fuel Cells A few KW to tens of MW DC to AC converter

Benefits & Drawbacks of DG:

Benefits: The idea behind connection of DG is to increase the reliability of power supply to the

customers, reduce losses in transmission and distribution networks, can also serve the growing





demand for higher power quality than the one provided by the grid. It will also improve the voltage

profile, power quality and support the voltage stability. This allows the system to withstand higher

loading conditions and defers the construction or upgrading of new transmission and distribution

infrastructures.

Some DG technologies have high overall efficiencies and low pollution such as combined heat and

power (CHP) and some micro-turbines. This contributes to the reduction of green house gases.

Drawbacks: DG technologies have some negative impact on the environment as well as economic

aspects. Wind turbines have visual, acoustic and bird-life impacts. Wind farms & PV systems need a

large area compare to conventional technologies. Small hydro, tidal and wave power plants may

influence the ecosystem and fishery. Biomass may produce unpleasant emissions in case of bad

combustion. Bad planning may lead to deforestation or conflict over using land & water resources.

So, distributed generation in the distribution networks may lead to energy conservation in the field of

electricity power sector.

ENERGY CONSERVATION IN THE UTILIZATION SECTOR12

: The fourth sector of the

energy conservation is the energy utilization sector, such as domestic sector, agricultural sector and

industrial sector.

Domestic Sector: In this sector, the maximum consumption of electricity is in water heating,

lighting, fans and other gadgets.

Household sector is seen as having an increasing share in energy use as a result of increase in

population and living standard.

Ranking of appliances indicate the opportunities available for conservation.

Using low wattage water heater of 500W instead instant water heater or geyser of 200W to

3000W reduces the energy requirement.

By reducing temperature setting of water heater by 100C, Rs. 1000/- per annum can be saved in

electricity bill. A 100 litre per day capacity solar water heater can save about 1000 units per year.

Hence the water heating can be switched to solar water heating.

Energy dependency on artificial lighting can be reduced by maximum use of sun light. Selection

of proper type of lamps suiting the standard requirement of illumination, proper placement & regular

maintenance helps for energy conservation. Efficient devices like CFLs and WLEDs (white LEDs)

consume the less power and longer life time.

0

20

40

60

%age increase in household electrical energy

0 10 20 30 40

Hea

tin

g

Ligh

tin

g

Co

olin

g

Co

oki

ng

TV e

tc.

Oth

ers

%age ranking of appliances





CFLs have almost completely penetrated the commercial market and the sales of CFLs in India

have grown from 20 million in 2003 to more than 150 million in 2013. However, the penetration into

houses is limited as the price is high. The price of CFL is still in the Rs. 80-100 range, whereas the

incandescent lamp is of Rs, 10-15 price range.

Adaptive lighting system is a lighting system with an intelligent control system that allows it to

dynamically respond to the current conditions of the area it illuminates. Each luminarie is equipped

with an occupancy sensor, a photosensor and a control.

Agricultural Sector: The farmers in the country have installed about 19 million pumps operated by

electricity. These consume 150 billion kWh. The pumping systems adapted have remained inefficient

and consumption of electricity has been more than 50% more. This excessively wasteful

consumption of energy reduces the irrigation cost for farmers. The aim of rectification of agricultural

pumps is energy conservation, which can be achieved by the following:-

Reduction in unnecessary frictional losses in the foot valves, suction and delivery lines of

centrifugal pumps. Frictionless foot valves and HDFE piping (high density poly ethylene) instead of

iron piping can save about 35% of energy.

Increasing operating efficiencies of the pumps and prime-movers in the duty range of discharge

and total head.

Use of shunt capacitors on the existing pump motors terminals, thus reducing frequent burnouts

due to low voltage. Conservation of energy also results in reduction of commercial losses.

Industrial Sector: Industries consume electrical energy for many purposes and their percentage

share is increasing. However, many industries are paying attention to energy auditing and

conservation opportunities since it reduce their cost of production by following observations:-

Aluminium industry smelting process consumes more than 90% of the total energy consumption.

Improved energy efficient designs such as ALCOA, carbothermic will reduce the consumption and

also improve the energy consumption.

Iron and steel plants have energy conservation in coke, ovens, basic oxygen furnace, sinter plants,

blast furnaces, reheating furnaces etc.

Fertilizer plants of nitrogenous, phosphatic, potassic and complex opportunities of energy savings

in several of its processes.

Cement industries can have measures of energy conservation by improving the kiln operational

efficiency, optimizing grinding efficiency, oxygen enrichment, variable speed drives. By these

observations, power consumption in modernized plants is 65-90 kWh for 1 ton of cement compared

with 95-120kWh in old plants.

Textile industries are equipped with highly energy efficient and old type coal fired boilers and

motors. Hence modifications in this will help in energy conservation.

Many industries like paper, sugar, ceramics, aluminium manufacturing and medium & small scale

industries are using old type furnaces, boilers, induction motors, diesel-generator sets etc. for several

applications. They need to have long-term industrial energy forecasting leading to modified or

replaced by energy efficient and environment friendly equipment.

CONCLUSIONS:

In today’s energy dependent times, the needs for ensuring energy conservation and energy efficiency

have become more crucial. The key areas are policy and institutional, end users and technology.

Some of important conclusions are listed as:-





The energy efficiency and conservation should be viewed as new source of energy and it is the

energy produced at very low cost. Having short pay-back period, it will help in reducing the gap

between the demand and supply.

It is necessary to bring attitudinal change in all energy users in respect of energy efficiency. This

can be achieved to large extent by imparting energy education in the school levels.

Energy efficiency is to be given due importance at the planning stage itself of the new industries.

Government, Industries and public participation can form immediate, medium term and long-term

measures to generate the pay-back periods.

The government should provide more attractive incentives in terms of soft loans for purchasing

energy efficient machines and subsidies for employing energy conservation measures.

A national movement for energy conservation can significantly reduce the need for fresh

investment in energy supply systems in coming years.

A systematic study and action plan approach for energy efficiency and energy conservation,

augmenting the electrical energy generation from conventional and renewable resources will address

the increasing energy demands of future India.

Efficient use of energy and its conservation will succeed as a programme if opinion leaders and

captains of industry take the lead in supporting the conservation programme.

Electrical energy conservation reduces the electricity bill, resource for nation, carbon dioxide

emissions for mankind and further reduction in the commercial losses.

REFERENCES:

1. S. Rao, Dr. B.B. Pabulekar, Energy Technology, 3rd

edition, 2007.

2. G.D. Rai, Non-Conventional Energy Sources, 4th

edition, 2008.

3. Sunil S. Rao, Extra High Voltage Engg. Edition, 2005

4. M. Siddhartha Bhatt-Scope of Energy Conservation in India, Journal: Electrical India, Edition

September, 2006.

5. M. Siddhartha Bhatt- Energy Efficiency in the Power Generation Sector-supply side options,

Journal: Electrical India, Edition December, 2013.

6. M. Siddhartha Bhatt- Energy Conservation in the Power Generation, Journal: Electrical India,

Edition January, 2014.

7. Technical Project Report on Energy Efficient Technologies in Transmission and Distribution,

June, 2014.

8. Technical report of ABB on HVDC by ABB AB Grid Systems – HVDC SE-771 80 Ludvika,

Sweden.

9. Technical report of Alstom Company Pvt. Ltd. on Gas Insulated Substation- manufacturing and

operation, commissioning of GIS substations.

10. Tsuyuki - A study of Electric Insulation of Superconducting DC cables, Cryogenic Engineering,

Vol. 35, No. 7 (2000).

11. Paresh R Modha, H.V. Rupareliya- Distributed Generation, Definition, Benefits, Major issues

and Impact on voltage profile, Journal: Electrical India, Edition, February, 2011.

12. Kamalapur G.D., Udaykumar, R. Y.-Need & challenges of Electrical Energy Conservation in

India, Journal: Electrical India, Edition December, 2013.


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