SMART GRID GITA,BBSR

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ABSTRACT

Today's alternating current power grid evolved after 1896, based in part on

Nikola Tesla's design published in 1888 (see War of Currents). At that time, the

grid was conceived as a centralized unidirectional system of electric power

transmission, electricity distribution, and demand-driven control.

In the 20th century power grids originated as local grids that grew over time,

and were eventually interconnected for economic and reliability reasons. By the

1960s, the electric grids of developed countries had become very large, mature

and highly interconnected, with thousands of 'central' generation power stations

delivering power to major load centres via high capacity power lines which

were then branched and divided to provide power to smaller industrial and

domestic users over the entire supply area. The topology of the 1960s grid was a

result of the strong economies of scale of the current generation technology:

large coal-, gas- and oil-fired power stations in the 1 GW (1000 MW) to 3 GW

scale are still found to be cost-effective, due to efficiency-boosting features that

can be cost effectively added only when the stations become very large.

A smart grid is a digitally enabled electrical grid that gathers, distributes, and

acts on information about the behavior of all participants (suppliers and

consumers) in order to improve the efficiency, importance, reliability,

economics, and sustainability of electricity services

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INTRODUCTION

Historical development of the electricity grid

Today's alternating current power grid evolved after 1896, based in part on

Nikola Tesla's design published in 1888. At that time, the grid was conceived as

a centralized unidirectional system of electric power transmission, electricity

distribution, and demand-driven control.

In the 20th century power grids originated as local grids that grew over time,

and were eventually interconnected for economic and reliability reasons. By the

1960s, the electric grids of developed countries had become very large, mature

and highly interconnected, with thousands of 'central' generation power stations

delivering power to major load centres via high capacity power lines which

were then branched and divided to provide power to smaller industrial and

domestic users over the entire supply area. The topology of the 1960s grid was a

result of the strong economies of scale of the current generation technology:

large coal-, gas- and oil-fired power stations in the 1 GW (1000 MW) to 3 GW

scale are still found to be cost-effective, due to efficiency-boosting features that

can be cost effectively added only when the stations become very large.

Power stations were located strategically to be close to fossil fuel reserves

(either the mines or wells themselves, or else close to rail, road or port supply

lines). Siting of hydro-electric dams in mountain areas also strongly influenced

the structure of the emerging grid. Nuclear power plants were sited for

availability of cooling water. Finally, fossil-fired power stations were initially

very polluting and were sited as far as economically possible from population

centres once electricity distribution networks permitted it. By the late 1960s, the

electricity grid reached the overwhelming majority of the population of

developed countries, with only outlying regional areas remaining 'off-grid'.

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Origin of the term 'smart grid'

The term smart grid has been in use since at least 2005, when it appeared in the

article "Toward A Smart Grid" of Amin and Wallenberg. The term had been

used previously and may date as far back as 1998. There are a great many smart

grid definitions, some functional, some technological, and some benefits-

oriented. A common element to most definitions is the application of digital

processing and communications to the power grid, making data flow and

information management central to the smart grid. Various capabilities result

from the deeply integrated use of digital technology with power grids, and

integration of the new grid information flows into utility processes and systems

is one of the key issues in the design of smart grids. Electric utilities now find

themselves making three classes of transformations: improvement of

infrastructure, called the strong grid in China; addition of the digital layer,

which is the essence of the smart grid; and business process transformation,

necessary to capitalize on the investments in smart technology. Much of the

modernization work that has been going on in electric grid modernization,

especially substation and distribution automation, is now included in the general

concept of the smart grid, but additional capabilities are evolving as well.

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SMART GRID

Smart grid refers to the next generation electric power network that makes use

of IT and high technologies. Compared to the telecommunication network, the

electric power network has not developed remarkably in terms of creating

innovative technologies. However, smart grid by revolutionizing the electric

power network and being almost as powerful as the internet, is attracting many

attentions among various industries.

Smart grid is a system that enables two-way communications in between

consumers and electric power companies. In a smart grid system consumer‘s

information is received by the electric power companies in order to provide the

most efficient electric network operations. In addition to the efficient operations of

a power plant, smart grids also make it possible to control power demand and

distributed energy, including renewable energies. By installing an intelligent meter

(smart meter) on the consumer side, especially households, monitoring the use of

energy becomes much easier and even helps to reduce carbon dioxide emissions.

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A smart grid delivers electricity from supplier to consumers using two- way

digital technology to control appliances at consumers‘ homes to save energy,

reduce cost and increase reliability and transparency. It overlays the electricity

distribution grid with an information and net metering system. Power travels from

the power plant to your house through an amazing system called the power

distribution grid. Such a modernized electricity networks is being promoted by

many governments as a way of addressing energy independences, global warming

and emergency resilience issues. Smart meters may be part of smart grid, but alone

do not constitute a smart grid.

Overview of smart grid

A smart grid includes an intelligent monitoring system that keeps track of all

electricity flowing in the system. It also incorporates the use of

superconductive transmission lines for less power loss, as well as the capability

of the integrating renewable electricity such as solar and wind. When power is

least expensive the user can allow the smart grid to turn on selected home

appliances such as washing machines or factory processes that can run at

arbitrary hours. At peak times it could turn off selected appliances to reduce

demand.

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Smart Grid And it’s Need

Understanding the need for smart grid requires acknowledging a few facts about

our infrastructure. The power grid is the backbone of the modern civilization, a

complex society with often conflicting energy needs-more electricity but fewer

fossil fuels, increased reliability yet lower energy costs, more secure distribution

with less maintenance, effective new construction and efficient disaster

reconstruction. But while demand for electricity has risen drastically, its

transmission is outdated and stressed. The bottom line is that we are exacting

more from a grid that is simply not up to the task.

POWER SYSTEM

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How“smart”should be a powergrid

The utilities get the ability to communicate with and control end user hardware,

from industrial- scale air conditioner to residential water heaters. They use that

to better balance supply and demand, in part by dropping demand during peak

usage hours.

Taking advantages of information technology to increase the efficiency of the

grid, the delivery system, and the use of electricity at the same time is itself a

smart move. Simply put, a smart grid combined with smart meters enables both

electrical utilities and consumer to be much more efficient.

A smart grid not only moves electricity more efficiently in geographic terms, it

also enables electricity use to be shifted overtime-for example, from period of

peak demand to those of off-peak demand. Achieving this goals means working

with consumers who have ―smart meters‖ to see exactly how much electricity

is being used at any particular time. This facilitates two-way communication

between utility and consumer. So they can cooperate in reducing peak demand

in a way that it‘s advantageous to both. And it allow to the use of two way

metering so that customer who have a rooftop solar electric panel or their own

windmill can sell surplus electricity back to the utility.

1. Intelligent –

Capable of sensing system overloads and rerouting power to prevent or

minimize a potential outage; of working autonomously when conditions

required resolution faster than humans can respond and co-operatively in

aligning the goals of utilities, consumers and regulators.

2. Efficient –

Capable of meeting efficient increased consumer demand without adding

infrastructure.

3. Accommodating –

Accepting energy from virtually any fuel source including solar and wind as

easily and transparently as coal and natural gas: capable of integrating any and

all better ideas and technologies – energy storage technologies. For e.g.- as they

are market proven and ready to come online.

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4. Motivating –

Enable real-time communication between the consumer and utility, so consumer

can tailor their energy consumption based on individual preferences, like price

and or environmental concerns.

5. Resilient –

Increasingly resistant to attack and natural disasters as it becomes more

decentralization and reinforced with smart grid security protocol.

6. Green –

Slowing the advance of global climate change and offering a genuine path

towards significant environmental improvement.

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Features of the smart grid

The smart grid represents the full suite of current and proposed responses to the

challenges of electricity supply. Because of the diverse range of factors, there

are numerous competing taxonomies, and no agreement on a universal

definition. Nevertheless, one possible categorisation is given here.

Reliability

The smart grid will make use of technologies that improve fault detection and

allow self-healing of the network without the intervention of technicians. This

will ensure more reliable supply of electricity, and reduced vulnerability to

natural disasters or attack.

Although multiple routes are touted as a feature of the smart grid, the old grid

also featured multiple routes. Initial power lines in the grid were built using a

radial model, later connectivity was guaranteed via multiple routes, referred to

as a network structure. However, this created a new problem: if the current flow

or related effects across the network exceed the limits of any particular network

element, it could fail, and the current would be shunted to other network

elements, which eventually may fail also, causing a domino effect. See power

outage. A technique to prevent this is load shedding by rolling blackout or

voltage reduction (brownout).

Flexibility in network topology

Next-generation transmission and distribution infrastructure will be better able

to handle possible bidirection energy flows, allowing for distributed

generation such as from photovoltaic panels on building roofs, but also the use

of fuel cells, charging to/from the batteries of electric cars, wind turbines,

pumped hydroelectric power, and other sources.

Classic grids were designed for one-way flow of electricity, but if a local sub-

network generates more power than it is consuming, the reverse flow can raise

safety and reliability issues. A smart grid aims to manage these situations.

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Efficiency

Numerous contributions to overall improvement of the efficiency of energy

infrastructure is anticipated from the deployment of smart grid technology, in

particular including demand-side management, for example turning off air

conditioners during short-term spikes in electricity price. The overall effect is

less redundancy in transmission and distribution lines, and greater utilisation of

generators, leading to lower power prices

Load adjustment

The total load connected to the power grid can vary significantly over time.

Although the total load is the sum of many individual choices of the clients, the

overall load is not a stable, slow varying, average power consumption. Imagine

the increment of the load if a popular television program starts and millions of

televisions will draw current instantly. Traditionally, to respond to a rapid

increase in power consumption, faster than the start-up time of a large

generator, some spare generators are put on a dissipative standby mode.A smart

grid may warn all individual television sets, or another larger customer, to

reduce the load temporarily (to allow time to start up a larger generator) or

continuously (in the case of limited resources). Using mathematical prediction

algorithms it is possible to predict how many standby generators need to be

used, to reach a certain failure rate. In the traditional grid, the failure rate can

only be reduced at the cost of more standby generators. In a smart grid, the load

reduction by even a small portion of the clients may eliminate the problem.

Peak curtailment/leveling and time of use pricing

To reduce demand during the high cost peak usage periods, communications

and metering technologies inform smart devices in the home and business when

energy demand is high and track how much electricity is used and when it is

used. It also gives utility companies the ability to reduce consumption by

communicating to devices directly in order to prevent system overloads. An

example would be a utility reducing the usage of a group of electric vehicle

charging stations. To motivate them to cut back use and perform what is called

peak curtailment or peak leveling, prices of electricity are increased during

high demand periods, and decreased during low demand periods. It is thought

that consumers and businesses will tend to consume less during high demand

periods if it is possible for consumers and consumer devices to be aware of the

high price premium for using electricity at peak periods. This could mean

making trade-offs such as cooking dinner at 9 pm instead of 5 pm. When

businesses and consumers see a direct economic benefit of using energy at off-

peak times become more energy efficient, the theory is that they will include

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energy cost of operation into their consumer device and building construction

decisions. See Time of day metering and demand response.

According to proponents of smart grid plans, this will reduce the amount of

spinning reserve that electric utilities have to keep on stand-by, as the load

curve will level itself through a combination of "invisible hand" free-market

capitalism and central control of a large number of devices by power

management services that pay consumers a portion of the peak power saved by

turning their devices off.

Sustainability

The improved flexibility of the smart grid permits greater penetration of highly

variable renewable energy sources such as solar power and wind power, even

without the addition of energy storage. Current network infrastructure is not

built to allow for many distributed feed-in points, and typically even if some

feed-in is allowed at the local (distribution) level, the transmission-level

infrastructure cannot accommodate it. Rapid fluctuations in distributed

generation, such as due to cloudy or gusty weather, present significant

challenges to power engineers who need to ensure stable power levels through

varying the output of the more controllable generators such as gas turbines and

hydroelectric generators. Smart grid technology is a necessary condition for

very large amounts of renewable electricity on the grid for this reason.

Market-enabling

The smart grid allows for systematic communication between suppliers (their

energy price) and consumers (their willingness-to-pay), and permits both the

suppliers and the consumers to be more flexible and sophisticated in their

operational strategies. Only the critical loads will need to pay the peak energy

prices, and consumers will be able to be more strategic in when they use energy.

Generators with greater flexibility will be able to sell energy strategically for

maximum profit, whereas inflexible generators such as base-load steam turbines

and wind turbines will receive a varying tariff based on the level of demand and

the status of the other generators currently operating. The overall effect is a

signal that awards energy efficiency, and energy consumption that is sensitive

the time-varying limitations of the supply. At the domestic level, appliances

with a degree of energy storage or thermal mass (such as refrigerators, heat

banks, and heat pumps) will be well placed to 'play' the market at seek to

minimise energy cost by adapting demand to the lower-cost energy support

periods. This is an extension of the dual-tariff energy pricing mentioned above.

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Demand response support

Demand response support allows generators and loads to interact in an

automated fashion in real time, coordinating demand to flatten spikes.

Eliminating the fraction of demand that occurs in these spikes eliminates the

cost of adding reserve generators, cuts wear and tear and extends the life of

equipment, and allows users to cut their energy bills by telling low priority

devices to use energy only when it is cheapest.

Currently, power grid systems have varying degrees of communication within

control systems for their high value assets, such as in generating plants,

transmission lines, substations and major energy users. In general information

flows one way, from the users and the loads they control back to the utilities.

The utilities attempt to meet the demand and succeed or fail to varying degrees

(brownout, rolling blackout, uncontrolled blackout). The total amount of power

demand by the users can have a very wide probability distribution which

requires spare generating plants in standby mode to respond to the rapidly

changing power usage. This one-way flow of information is expensive; the last

10% of generating capacity may be required as little as 1% of the time, and

brownouts and outages can be costly to consumers.

Latency of the data flow is a major concern, with some early smart meter

architectures allowing actually as long as 24 hours delay in receiving the data,

preventing any possible reaction by either supplying or demanding devices.

Platform for advanced services

As with other industries, use of robust two-way communications, advanced

sensors, and distributed computing technology will improve the efficiency,

reliability and safety of power delivery and use. It also opens up the potential

for entirely new services or improvements on existing ones, such as fire

monitoring and alarms that can shut off power, make phone calls to emergency

services, etc.

Provision megabits, control power with kilobits, sell

the rest

The amount of data required to perform monitoring and switching your

appliances off automatically is very small compared with that already reaching

even remote homes to support voice, security, and Internet and TV services.

Many smart grid bandwidth upgrades are paid for by over-provisioning to also

support consumer services, and subsidizing the communications with energy-

related services or subsidizing the energy-related services, such as higher rates

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during peak hours, with communications. This is particularly true where

governments run both sets of services as a public monopoly, e.g. in India.

Because power and communications companies are generally separate

commercial enterprises in North America and Europe, it has required

considerable government and large-vendor effort to encourage various

enterprises to cooperate. Some, like Cisco, see opportunity in providing devices

to consumers very similar to those they have long been providing to industry.

Others, such as Silver Spring Networks or Google, are data integrators rather

than vendors of equipment. While the AC power control standards suggest

powerline networking would be the primary means of communication among

smart grid and home devices, the bits may not reach the home via Broadband

over Power Lines (BPL) initially but by fixed wireless. This may be only an

interim solution, however, as separate power and data connections defeats full

control.

Technology

The bulk of smart grid technologies are already used in other applications such

as manufacturing and telecommunications and are being adapted for use in grid

operations. In general, smart grid technology can be grouped into five key areas.

Integrated communications

Some communications are up to date, but are not uniform because they have

been developed in an incremental fashion and not fully integrated. In most

cases, data is being collected via modem rather than direct network connection.

Areas for improvement include: substation automation, demand response,

distribution automation, supervisory control and data acquisition (SCADA),

energy management systems, wireless mesh networks and other technologies,

power-line carrier communications, and fiber-optics. Integrated

communications will allow for real-time control, information and data exchange

to optimize system reliability, asset utilization, and security.

Sensing and measurement

Core duties are evaluating congestion and grid stability, monitoring equipment

health, energy theft prevention, and control strategies support. Technologies

include: advanced microprocessor meters (smart meter) and meter reading

equipment, wide-area monitoring systems, dynamic line rating (typically based

on online readings by Distributed temperature sensing combined with Real time

thermal rating (RTTR) systems), electromagnetic signature

measurement/analysis, time-of-use and real-time pricing tools, advanced

switches and cables, backscatter radio technology, and Digital protective relays.

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Smart meters

A smart grid replaces analog mechanical meters with digital meters that record

usage in real time. Smart meters are similar to Advanced Metering

Infrastructure meters and provide a communication path extending from

generation plants to electrical outlets (smart socket) and other smart grid-

enabled devices. By customer option, such devices can shut down during times

of peak demand.

Phasor measurement units

High speed sensors called PMUs distributed throughout their network can be

used to monitor power quality and in some cases respond automatically to them.

Phasors are representations of the waveforms of alternating current, which

ideally in real-time, are identical everywhere on the network and conform to the

most desirable shape. In the 1980s, it was realized that the clock pulses from

global positioning system (GPS) satellites could be used for very precise time

measurements in the grid. With large numbers of PMUs and the ability to

compare shapes from alternating current readings everywhere on the grid,

research suggests that automated systems will be able to revolutionize the

management of power systems by responding to system conditions in a rapid,

dynamic fashion. A wide-area measurement system (WAMS) is a network of

PMUS that can provide real-time monitoring on a regional and national scale.

Many in the power systems engineering community believe that the Northeast

blackout of 2003 would have been contained to a much smaller area if a wide

area phasor measurement network was in place.

Advanced components

Innovations in superconductivity, fault tolerance, storage, power electronics,

and diagnostics components are changing fundamental abilities and

characteristics of grids. Technologies within these broad R&D categories

include: flexible alternating current transmission system devices, high voltage

direct current, first and second generation superconducting wire, high

temperature superconducting cable, distributed energy generation and storage

devices, composite conductors, and ―intelligent‖ appliances.

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Advanced control

Power system automation enables rapid diagnosis of and precise solutions to

specific grid disruptions or outages. These technologies rely on and contribute

to each of the other four key areas. Three technology categories for advanced

control methods are: distributed intelligent agents (control systems), analytical

tools (software algorithms and high-speed computers), and operational

applications (SCADA, substation automation, demand response, etc.). Using

artificial intelligence programming techniques, Fujian power grid in China

created a wide area protection system that is rapidly able to accurately calculate

a control strategy and execute it.The Voltage Stability Monitoring & Control

(VSMC) software uses a sensitivity-based successive linear programming

method to reliably determine the optimal control solution

Improved interfaces and decision support

Information systems that reduce complexity so that operators and managers

have tools to effectively and efficiently operate a grid with an increasing

number of variables. Technologies include visualization techniques that reduce

large quantities of data into easily understood visual formats, software systems

that provide multiple options when systems operator actions are required, and

simulators for operational training and ―what-if‖ analysis.

Smart power generation

Smart power generation is a concept of matching electricity production with

demand using multiple identical generators which can start, stop and operate

efficiently at chosen load, independently of the others, making them suitable for

base load and peaking power generation. Matching supply and demand, called

load balancing, is essential for a stable and reliable supply of electricity. Short-

term deviations in the balance lead to frequency variations and a prolonged

mismatch results in blackouts. Operators of power transmission systems are

charged with the balancing task, matching the power output of the all the

generators to the load of their electrical grid. The load balancing task has

become much more challenging as increasingly intermittent and variable

generators such as wind turbines and solar cells are added to the grid, forcing

other producers to adapt their output much more frequently than has been

required in the past.First two dynamic grid stability power plants utilizing the

concept has been ordered by Elering and will be built by Wärtsilä in Kiisa,

Estonia. Their purpose is to "provide dynamic generation capacity to meet

sudden and unexpected drops in the electricity supply." They are scheduled to

be ready during 2013 and 2014, and their total output will be 250 MW.

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Economics of “SMART GRID”

Market outlook : In 2009, the US smart grid industry was valued at about $21.4 billion –

by 2014, it will exceed at least $42.8 billion. Given the success of the

smart grids in the U.S., the world market is expected to grow at a faster

rate, surging from $69.3 billion in 2009 to $171.4 billion by 2014. With

the segments set to benefit the most will be smart metering hardware

sellers and makers of software used to transmit and organize the massive

amount of data collected by meters.

General economic developments : As customers can choose their electricity suppliers, depending on their

different tariff methods, the focus of transportation costs will be

increased. Reduction of maintenance and replacements costs will

stimulate more advanced control.

A smart grid precisely limits electrical power down to the residential level,

network small-scale distributed energy generation and storage devices,

communicate information on operating status and needs, collect information

on prices and grid conditions, and move the grid beyond central control to a

collaborative network.

US and UK savings estimates and concerns :

One United States Department of Energy study calculated that internal

modernization of US grids with smart grid capabilities would save between 46

and 117 billion dollars over the next 20 years. As well as these industrial

modernization benefits, smart grid features could expand energy efficiency

beyond the grid into the home by coordinating low priority home devices such

as water heaters so that their use of power takes advantage of the most desirable

energy sources. Smart grids can also coordinate the production of power from

large numbers of small power producers such as owners of rooftop solar

panels — an arrangement that would otherwise prove problematic for power

systems operators at local utilities.

One important question is whether consumers will act in response to market

signals. In the UK, where consumers have had a choice of supply company

from which to purchase electricity since 1998, almost half have stayed with

their existing supplier, despite the fact that there are significant differences in

the prices offered by a given electricity supplier. Where consumers switch an

estimated 27-38% of consumers are worse off as a result.

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Another concern is that the cost of telecommunications to fully support smart

grids may be prohibitive. A less expensive communication mechanism is

proposed using a form of "dynamic demand management" where devices shave

peaks by shifting their loads in reaction to grid frequency. Grid frequency could

be used to communicate load information without the need of an additional

telecommunication network, but it would not support economic bargaining or

quantification of contributions.

Although there are specific and proven smart grid technologies in use, smart

grid is an aggregate term for a set of related technologies on which a

specification is generally agreed, rather than a name for a specific technology.

Some of the benefits of such a modernized electricity network include the

ability to reduce power consumption at the consumer side during peak hours,

called demand side management; enabling grid connection of distributed

generation power (with photovoltaic arrays, small wind turbines, micro hydro,

or even combined heat power generators in buildings); incorporating grid

energy storage for distributed generation load balancing; and eliminating or

containing failures such as widespread power grid cascading failures. The

increased efficiency and reliability of the smart grid is expected to save

consumers money and help reduce CO2 emissions.

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Enabling Technology

The bulk of smart grid technologies are already used in other applications such

as manufacturing and telecommunications and are being adapted for use in grid

operations. In general, smart grid technology can be grouped into five key areas

I. Integrated communications

Some communications are up to date, but are not uniform because they have

been developed in an incremental fashion and not fully integrated. In most

cases, data is being collected via modem rather than direct network connection.

Areas for improvement include: substation automation, demand response,

distribution automation, supervisory control and data acquisition (SCADA),

energy management systems, wireless mesh networks and other technologies,

power- line carrier communication s and fiber-optics. Integrated communication

will allow for real time control, information and data exchange to optimize

system reliability, asset utilization, and security.

II. Sensing and measurement

Core duties are evaluating congestion and grid stability, monitoring equipment

health, energy theft prevention, and control strategies support. Technologies

include: advanced microprocessor meters (smart meter) and meter reading

equipment, wide-area monitoring system, dynamic line rating(typically based

on online reading by distributed temperature sensing combined with Real time

thermal rating (RTTR) systems), electromagnetic signature

measurement/analysis, time-of-use and real-time pricing tools, advanced

switches and cables, backscatter radio technology, and Digital protective relays.

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III. Smart meters

A smart grid replaces analog mechanical meters with digital meters that record

usage in real time. Smart meters are similar to Advanced Metering

Infrastructure meters and provide a communication path extending from

generation plants to electrical outlets (smart socket) and other smart grid-

enabled devices. By customer option, such devices can shut down during times

of peak demand.

IV. Advanced components

Innovations in superconductivity, fault tolerance, storage, power electronics,

and diagnostics components are changing fundamental abilities and

characteristics of grids. Technologies within these broad R&D categories

include: flexible alternating current transmission system devices, high voltage

direct current, first and second generation superconducting wire, high

temperature superconducting cable, distributed energy generation and storage

devices, composite conductors, and ―intelligent‖ appliances.

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ENERGY CONSERVATION

TECHNIOUES

ENERGY CONSERVATION IN TRANSMISSION

SYSTEM:

Transformer is a static device. It does not have any moving parts. So, a

transformer is free from mechanical and frictional losses. Thus, it faces only

electrical losses and magnetic losses. Hence the efficiency of conventional

transformer is high around 95-98%.

Thus, energy conservation opportunities for transformer are available only in

design and material used. Also optimizing loading of transformer can increase

efficiency of system.

ENERGY CONSERVATION TECHNIQUES IN

TRANSFORMER

OPTIMIZATION OF LOADING OF TRANSFORMER

The environmental protection agency (EPA) brought study report that nearly 61

billion K WH of electricity is wasted in each year only as transformer losses.

Study of typical grid system showed that, power transformer contributes nearly

40% to 50% of total transmission and distribution losses.

Maintaining maximum efficiency to occur at 38% loading (as recommended by

REC), the overall efficiency of transformer can be increased and its losses can

be reduced. The load loss may be even reduced by using thicker conductors.

Transformer ratings Reduction in losses at 38% loading

25 KVA 685-466W

63KVA 1235-844W

100KVA 1760-1196W

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IMPROVISION IN DESIGN AND MATERIAL OF

TRANSFORMER

This is nothing but the reducing No-Load losses or Core Losses. They can be reduced

by following methods:-

1) BY USING ENERGY EFFICIENT TRANSFORMER-

By using superior quality or improved grades of CRGO (Cold Rolled Grain Oriented)

laminations, the no-load losses can be reduced to 32%.

2) BY USING AMORPHOUS TRANSFORMER

Transformer with superior quality of core material i.e. amorphous alloy is called

Amorphous Transformers. Amorphous alloy is made up of Iron-boron-silicon

The magnetic core of this transformer is made with amorphous metal, alloy.

which is easily magnetized / demagnetized. Typically, core loss can be 70–80%

less than its molten metal mixture when cooled to solid state at a very high

speed rate, retain a random atomic structure that is not crystalline. This is called

Amorphous.

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Amorphous transformer

ENERGY CONSERVATION IN TRANSMISSION

LINE:-

Transmission losses can be reduced as follows:-

1) BY REDUCING RESISTANCE -

Losses are directly proportional to I2r in conductor. So, if we reduce ‗R‘ from

this surely the losses will be reduced. For this we can use stranded or bundled

conductors or ACSR conductors. And even this method is been adopted and

also successful.

ACC ACSR Conductor

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2) BY CONTROLLING VOLTAGE LEVELS -

This can be done by following methods-

1. by using voltage controllers

2. by using voltage stabilizer

3. By using power factor controller

AWRENESS IN CONSUMERS -

This is one of most important and useful/helpful for energy conservation. This

can be done by asking consumer to make use of energy efficient equipments, by

giving seminar about energy conservation and make them aware and understand

about the happening and there advantages and disadvantages etc.

Effective use of smart grid technologies by customer helps utilities –

Optimizes grid use.

Improve grid efficiency and security.

Better align demand with supply constraints & grid congestion.

Enable distributed generation (especially from renewable sources)

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ENERGY CONSERVATION IN

DISTRIBUTION SYSTEM :-

This is done by considering following points:-

1) BALANCING OF PHASE LOAD-

As a result of unequal loads on individual phase sequence,

components causes over heating of transformers, cables, conductors

motors. Thus, increasing losses and resulting in the motor

malfunctioning under unbalanced voltage conditions. Thus, keeping the

system negative phase sequence voitage within limits, amount of savings

in capital (saving the duration of equipment )as well as energy losses.

Thus, to avoid this losses, the loads are distributed evenly ‗as is practical‘

between the phases.

1) POWER FACTOR IMPROVEMENT-

Low power factor will lead to increased current and hence increase

losses and will affect the voltage. The power factor at peak is almost

unity. However, during off peak hours, mainly (11 am to 3 pm ) the

power factor decreases to around 0.8, this may be due to following

reasons,

Wide use of fans.

Wide industrial loads.

Wide use of agricultural and domestic pumping motors.

Less use of high power factor loads like lightube etc.

Now, to improve power factor at off peak hours the

consumers must be aware of the effects of low power factor and must

connect compensation equipment DSTACOM, capacitor bank.

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SMART METERS

A smart meter generally refers to a type of advanced meters that identifies

consumption in more detail than a conventional meter and communicates that

information back to the local utility for monitoring and billing, a process known

as telemetering.

These meters includes additional functions to power measurement such as

communication, data storage, remote programming, and time-of-use rates, and

are intended to be deployed as advanced metering infrastructure (AMI) solution.

Smart meters are the next generation of electricity and gas meters. Smart meter

will empower customer to make choices on how much energy they use.

Supplier will install two-way communication system that display accurate real

time information on energy use in the home to the consumer and back to the

energy supplier.

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COMPONENTS USED

ATMEGA 16

PIN DIAGRAM OF ATMEGA 16

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The ATmega16 is a low-power CMOS 8-bit microcontroller based on the AVR

enhanced RISC architecture. By executing powerful instructions in a single

clock cycle, the ATmega16 achieves throughputs approaching 1 MIPS per MHz

allowing the system designed to optimize power consumption versus processing

speed.

Pin Descriptions

VCC Digital supply voltage.

GND Ground.

Port A (PA7..PA0)

Port A also serves as an 8-bit bi-directional I/O port, if the A/D Converter is not

used. Port pins can provide internal pull-up resistors (selected for each bit). The

Port A output buffers have symmetrical drive characteristics with both high sink

and source capability. When pins PA0 to PA7 are used as inputs and are

externally pulled low, they will source current if the internal pull-up resistors

are activated. The Port A pins are tri-stated when a reset condition becomes

active,even if the clock is not running

Port B (PB7..PB0)

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected

for each bit). The Port B output buffers have symmetrical drive characteristics

with both high sink and source capability. As inputs, Port B pins that are

externally pulled low will source current if the pull-up resistors are activated.

The Port B pins are tri-stated when a reset condition becomes active,

even if the clock is not running.

Port C (PC7..PC0)

Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected

for each bit). The Port C output buffers have symmetrical drive characteristics

with both high sink and source capability. As inputs, Port C pins that are

externally pulled low will source current if the pull-up resistors are activated.

The Port C pins are tri-stated when a reset condition becomes active,even if the

clock is not running. If the JTAG interface is enabled, the pull-up resistors on

pins PC5 (TDI), PC3 (TMS) and PC2 (TCK) will be activated even if a reset

occurs.

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Port D (PD7..PD0)

Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected

for each bit). The Port D output buffers have symmetrical drive characteristics

with both high sink and source capability. As inputs, Port D pins that are

externally pulled low will source current if the pull-up resistors are activated.

The Port D pins are tri-stated when a reset condition becomes active,even if the

clock is not running.

RESET Reset Input.

A low level on this pin for longer than the minimum pulse length will generate a

reset, even if the clock is not running.

XTAL1

Input to the inverting Oscillator amplifier and input to the internal clock

operating circuit.

XTAL2

Output from the inverting Oscillator amplifier.

AVCC

AVCC is the supply voltage pin for Port A and the A/D Converter. It should be

externally connected to VCC, even if the ADC is not used. If the ADC is used,

it should be connected to VCC through a low-pass filter.

AREF

AREF is the analog reference pin for the A/D Converter

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DTMF

The MT8870 is an 18-pin IC. It is used in telephones and a variety of other

applications. When a proper output is not obtained in projects using this IC,

engineers or technicians need to test this IC separately. A quick testing of this

could save a lot of time in research labs and manufacturing industries of

communication instruments. Here‘s a small and handy tester circuit for the

DTMF IC. It can be assembled on a multipurpose PCB with an 18-pin IC base.

One can also test the IC on a simple breadboard. For optimum working of

telephone equipment, the DTMF receiver must be designed to recognize a valid

tone pair greater than 40 ms in duration and to accept successive digit tone-pairs

that are

Greater than 40 ms apart. However, for other applications like remote controls

and Radio communications, the tone duration may differ due to noise

considerations. Therefore, by adding an extra resistor and steering diode the

tone duration can beset to different values.

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The Status of LEDs on Pressing Keys

The circuit is configured in balanced line mode. To reject common-mode noise

signals, a balanced differential amplifier input is used. The circuit also provides

an excellent bridging interface across a properly terminated telephone line.

Transient protection may be achieved by splitting the input resistors and

inserting zener diodes (ZD1 and ZD2) to achieve voltage clamping. This allows

the transient energy to be dissipated in the resistors and diodes, and limits the

maximum voltage that may appear at the inputs. Whenever you press any key

on your local telephone keypad, the delayed steering (Std) output of the IC goes

high on receiving the tone pair, causing LED5 (connected )to pin 15 of IC via

resistor R15) to glow. It will be high for a duration depending on the values of

capacitor and resistors at pins 16 and 17. The MT8870D/MT8870D-1 is a

complete DTMF receiver integrating both the band split filter and digital

decoder functions. The filter section uses switched capacitor techniques for high

and low group filters; the decoder uses digital counting techniques to detect and

decode all 16 DTMF tone pairs into a 4-bit code. External component count is

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minimized by on chip provision of a differential input amplifier, clock oscillator

and latched three-state bus interface.

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LCD

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IC 7805

The MC78XX/LM78XX/MC78XXA series of three terminal positive

regulators are available in the TO-220/D-PAK package and with

several fixed output voltages, making them useful in a wide range of

applications. Each type employs internal current limiting, thermal

shut down and safe operating area protection, making it essentially

indestructible. If adequate heat sinking is provided, they can deliver

over 1A output current. Although designed primarily as fixed voltage

regulators, these devices can be used with external components to

obtain adjustable voltages and currents.

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BLOCK DIAGRAM OF 7805

Electrical Characteristics (MC7805/LM7805)

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RELAY

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BLOCK DIAGRAM OF THE

CIRCUIT

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Working Principle

Smart grid does a lot of works. It is not possible to demonstrate each of the

tasks in a single project. So an attempt is made to demonstrate some of its

functions like automatic scheduling, power shading, distance controls etc.

Description of loads:

1. Two simple houses representing a colony

2. A hospital

3. An industry

In case of the colony, the houses are supplied by the main supply. In case

of power cut, they are being supplied by the storage which is represented

by an UPS.

But when the storage discharges fully in case of long power cut, then the

colony remains in dark.

In the hospital, since many of the biomedical equipment like breather are

running continuously on the electricity, so there is an interruptible need of

electric supply.

So, for the hospital, an arrangement is made such that if the main supply

goes off, then it is being supplied by UPS. When UPS discharges, then it

is being supplied by another energy source representing renewable energy

source.

In case of Industry, two loads are shown by means of two bulbs. The first

load in the industry is its normal load and the second one is extra or

overload.

During normal operation, it is being supplied by the main supply. During

power cut, it is being supplied by the renewable energy source.

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In case of overload, a notification is given to the colony or general

consumers in form of a buzzer and then after sometime the power is cut

in the colony for load shading purpose.

All these devices and operation are controllable by mobile showing the latest

distance supervision and operation functions. This is done by means of DTMF

(dual tone multiple frequency).

Fig: Smart Grid

Here as can be seen, the main power supply is directly connected to the UPS

and then to the colony loads. This makes the houses to work under main power

cut conditions also by the use of UPS.

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Fig: UPS representing storage in the grid

Here as can be seen, in the UPS, a dc storage is there in form of lead-acid

battery followed by an inverter circuit and then by a transformer. Under normal

condition when main supply is there, the battery get charged. 230v ac is

stepped-down to approx.17v ac and is then rectified to 12v dc to charge the

battery.

In case of power cut, the storage acts as the source. 12v dc is converted to

approx. 17v ac by the use of inverter circuit and then is stepped-up to 230v ac to

supply to the loads.

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Fig: transformer with rectifier ckt. Fig: 2C relays

As can be seen in the figure, in the first circuit, the supply from UPS is also

stepped down to approx. 17v ac by means of a transformer and is then rectified

to 12v ac to operate the 2C relay.

The rectified output is given to the exciting coil of the 2c relay. Normally the

plate is attached to the NC pin of the relay under not excited condition. So we

have attached the NO (normally open) pin to the main supply, so that in case of

main power on, the supply is provided by the main to the hospital.

In case the mains gets off, the UPS supplies the hospital load. And if UPS too

gets discharged in case of long power cut, then the renewable energy source

connected to the NC (normally closed) pin comes into action and supplies the

hospital load.

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In case of industry too, the same concept is used. Ac supply from mains is

stepped-down to be rectified to yield 12v dc to run the relay. In case the mains

gets off, the renewable energy source supplies the industry load.

Another complication has also been added to the industry to show the load

shading. In case the extra or overload is on, a buzzer is made on by the help of

microcontroller and then after some time the colony power cut happens.

In addition to all these, all the loads can be controlled individually by using a

mobile phone showing the distance operation using DTMF technology. For this

purpose, a 1c relay each is connected to individuals loads.

Also, the UPS charging or not charging can be controlled by distance operation

using DTMF technology.

Fig: relays with loads.

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COMPARISION BETWEEN TODAY’S GRID AND SMART GRID

(MODERN GRID)

Characteristics Today‘s grid Smart grid (Modern

grid)

1) Self-heals Respond to prevent further

damage. focus is on

protection of assets

following system faults.

Automatically detects &

respond to actual &

emerging transmission

&distribution problems.

Focus is on prevention.

minimizes computer

impacts.

2) Motivates &

includes the

consumers

Consumers are uniformed

&non-participative with the

power system.

Informed involve &active

consumers. Broad

penetration of demand

response.

3) Resist attack Vulnerable to malicious

acts of terrors natural

disasters.

Resilient to attach &natural

disasters with rapid

restoration capabilities.

4) Provided power

quality for 21st

century needs

Focused on outstage rather

than power quality

problems. Solve response in

revolving PQ issues.

Quality of power meets

industry standards &

consumers need. PQ issues

identified &revolved prior

to manifestation. Various

levels of PQ at various

prices.

5) Accommodates all

generation and

storage option.

Relatively small no. of

large generating plants.

numerous obstacles exist

for interconnecting DER.

Very large no. of diverse

distributed generation &

storage devices deployed to

complements the large

generating plant.

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Obstacles & Challenges

In Europe and the US, significant impediments exist to the widespread adoption

of smart grid technologies, including:

Regulatory environments that don't reward utilities for operational

efficiency, excluding U.S. awards.

consumer concerns over privacy,

social concerns over "fair" availability of electricity,

social concerns over Enron style abuses of information leverage,

Limited ability of utilities to rapidly transform their business and

operational environment to take advantage of smart grid technologies.

concerns over giving the government mechanisms to control the use of all

power using activities, and

Concerns on computer security.

Before a utility installs an advanced metering system, or any type of smart

system, it must make a business case for the investment. Some components, like

the power system stabilizers (PSS) installed on generators are very expensive,

require complex integration in the grid's control system, are needed only during

emergencies, but are only effective if other suppliers on the network have them.

Without any incentive to install them, power suppliers don't. Most utilities find

it difficult to justify installing a communications infrastructure for a single

application (e.g. meter reading). Because of this, a utility must typically identify

several applications that will use the same communications infrastructure – for

example, reading a meter, monitoring power quality, remote connection and

disconnection of customers, enabling demand response, etc. Ideally, the

communications infrastructure will not only support near-term applications, but

unanticipated applications that will arise in the future. Regulatory or legislative

actions can also drive utilities to implement pieces of a smart grid puzzle. Each

utility has a unique set of business, regulatory, and legislative drivers that guide

its investments. This means that each utility will take a different path to creating

their smart grid and that different utilities will create smart grids at different

adoption rates.

Some features of smart grids draw opposition from industries that currently are,

or hope to provide similar services. An example is competition with cable and

DSL Internet providers from broadband over power line internet access.

Providers of SCADA control systems for grids have intentionally designed

proprietary hardware, protocols and software so that they cannot inter-operate

with other systems in order to tie its customers to the vendor.

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With the advent of cybercrime there is also concern on the security of the

infrastructure, primarily that involving communications technology. Concerns

chiefly center around the communications technology at the heart of the smart

grid. Designed to allow real-time contact between utilities and meters in

customers' homes and businesses, there is a very real risk that these capabilities

could be exploited for criminal or even terrorist actions. One of the key

capabilities of this connectivity is the ability to remotely switch off power

supplies, enabling utilities to quickly and easily cease or modify supplies to

customers who default on payment. This undoubtedly a massive boon for

energy providers, but also raises some significant security issues.

Cybercriminals have infiltrated the U.S. electric grid before on numerous

occasions. Aside from computer infiltration, there are also concerns that

computer malware like Stuxnet, which targeted systems on the SCADA

software language widely used in industry, could do to a smart grid network

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PROS & CONS

Advantages Of Smart Grid-

Reduces the cost of blackouts.

Helps measure and reduces energy conservation and costs.

Help businesses to reduce their carbon footprints.

Opens up new opportunities for tech companies meaning more jobs created.

Disadvantages of Smart Grid

Biggest concern: it has security and privacy.

Two-way communication between power consumer and provider and

sensors so it is costly.

Some type of meter can hacked.

HACKER-

Gain control of thousand even millions, of meters.

Increases or decreases the demand of power.

Not simply a single component .various technology components are used

are software, system integrators, the power generators.

Future –

In the new future, will not be any vast development.

Risky because of financial developments and regulations.

In the long run, attitudes will change, wide spread usage of the smart grid

from every business to every home just like the internet.

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Resources of information

Articles –

Energy Conservation Through Energy Management

- by Prof. S. P. Rath (IEEMA magazine, January

2008)

WIRELESS Transmission Of Electric Power

- by Syed Khadeerullah (Electrical India magazine, January

2008)

Magazine of “Electrical India 2010”

Websites:-

www.nima.com

www.howstuffworks.com

www.wikipedia.com

www.xcelenergy.com/smartgridcity

www.schneider.com

www.powersmiths.com

www.renewableenrgyworld.com