at & c

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Definitions

T&D Losses: -

T&D losses are the difference between energy supplied and

energy billed

AT&C Losses: -

The difference between the number of units of energy supplied

and the number of units of energy for which payment is actually

recovered. Aggregate Technical and Commercial (AT&C) loss hasbeen prescribed as the performance parameter combining

distribution loss and commercial efficiency.

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Concept of AT&C

Energy

Input

(Units)

Energy

Consumption

(Units)

Energy Billed

To Consumers

(Units)

Amount

Billed

To

Consumers

(Rupees)

Average Tariff =

Amount Billed/ Units Billed

Amount

Recovered

(Rupees)

Units

Recovered

(Units)

Units Recovered =

Amount Recovered/ Average Tariff

Technical Losses Billing Gap

Recovery Gap

T&D Loss

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AT&C LOSSES IN T&D

To determine the AT&C Loss we need to proceed in followingsteps:

(i) T&D loss (the difference between the units billed and the unitsinput into the DISCOM)

(ii) Collection efficiency (as the ratio of amount billed to amountcollected)

(iii) Units realized (as the product of units billed and the collectionefficiency)

(iv) AT&C losses, as the difference between units realized andunits input into the DISCOM as a ratio of units input into theDISCOM.

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AT&C Loss Illustration

Average Retail Tariff [ D = C/B = Rs. 4/unit ]

Units Billed to consumers

[B=60 Units]

Units Purchased From

Transco

[A=100 Units]

Amount Realized by Discoms

[E = Rs. 200]

Units collected

[F = E/D = 50 Units]

Technical &

commercial losses

Collection

Losses

Amount Billed to consumers

[C= Rs.240]

AT&C losses = (A-F)/F = (100 50)/100 = 50%

40%17%

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AT&C Formulae

AT&C Loss

= 1 (Units Recovered/ Units Input)

= 1 (Billing Efficiency X Collection Efficiency) Billing Efficiency

= Units Billed/ Units Input

Collection Efficiency

= Amount Recovered/ Amount Billed Realization per Unit Input

= Amount Recovered/ Units Input

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AT&C LOSSES IN T&D

GENERATION

100%

TRANSMISSION

4%

DISTRIBUTION

(10+10)%

BILLING

80%

COLLECTION

80%

104 UNITS 100 UNITS 80 UNITS 64 UNITS 51 UNITS

TYPICAL AT&C LOSS VALUE

AT&C LOSS = 49 UNITS

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Why AT&C Reduction

Reduction in AT&C losses will mean lesser drain of Govt.

resources.

Making the Distribution business financially viable for privateparticipation.

Better utilization of the generation capacity available.

Better Quality and Reliable supply.

Rationalization of tariff and reduction.

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Basic Components of AT&C Loss

15%

15%

20%30%

10%10%

Technical

Theft

Metering

BillingCollection

Other

Percentage shared by AT & C Losses

(NDPL)

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AT&C LOSSES IN T&D

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Technical

Sub-transmission (66kV/33kV)

Distribution (11kV & below)

Direct theft

Un-metered

Un-authorized Colonies

Street Lights Poles

Metering

Import/Export metering errorsStop meter /Slow meter

Defective meter

CT Ratio errors

Billing Process DeficienciesMeters not read

Consumer not billed / under-

billed

Provisional billing

Bills not deliveredBills on account of old meter

when changed

Collection

Collection inefficiency

Part Payment

Others

Consumer billed but not credited

Un-authorized colonies/JJ

ClustersMisuse of category

Further BreakFurther Break--Up of AT&C LossUp of AT&C Losscomponentscomponents

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1. Lengthy Distribution lines, Inadequate size of conductor,

Distribution Transformers not located at Load center on the

Secondary Distribution System :

Reduce conductor length up to suitable size.

Increase conductor size.

Install new transformers. Bifurcate or Trifurcate feeders.

Energy audit

TECHNICAL FACTORS SOLUTIONSTECHNICAL FACTORS SOLUTIONS

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2. Lower power factor

Shunt capacitors are connected on the secondary side(11KV side) of the 33/11 KV power transformers.

Line losses in LT distribution lines may also be considerablyreduced by installing shunt capacitors of optimum ratingat vantage points.

3.

Losses in meter coils

To reduce these losses electronic meters are the bestsolution


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4. Bad Workmanship Resulting in Poor Contacts at Joints and

Connections:

Joints are a source of power loss.

Connections to the transformer bushing-stem, drop out

fuse, isolator, and LT switch etc. should be periodically

inspected Replacement of deteriorated wires and services


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100 % Metering

Meter at each level of distribution network i.e. at

transformers and consumers

Due to 100% metering of consumer utility can have

an account of subsidized units of electricity in

comparison to the actual consumption of subsidized

consumer.

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Sl. STATE 11kV Feeders Consumers

Numbers Metered %age Balance Numbers (In

Lakh)

Metered (In

Lakh)

%age Balance (In

Lakh)

1AP 7401 7401 100 0 198.6 181.2 91 17.4

2Arunachal

Pradesh

201 1 0 200 1.13 0.52 46 0.6

3Assam 708 452 64 256 11.77 10.56 90 1.2

4Bihar 1125 465 41 660 12.5 6.23 50 6.35Chattisgarh 1006 707 70 299 63.96 45.85 72 18.1

6Delhi 1591 1591 100 0 27.31 27.31 100 0

7Goa 179 179 100 0 3.92 3.74 95 0.2

8Gujarat 5307 5307 100 0 74.77 69.57 93 5.2

9Haryana 3888 3888 100 0 39.17 36.12 92 3.1

10HP 858 765 89 93 15.85 15.85 100 0

11J & K 1558 630 40 928 10 4 40 6

12Jharkand 461 396 86 65 6.53 4.02 62 2.513Karnataka 3518 3518 100 0 120.45 96.74 80 23.7

14Kerala 1320 1320 100 0 72.21 72.21 100 0

15MP 5660 5660 100 0 65.3 40.98 63 24.3

16Maharashtra 7128 6896 97 232 147 128.97 88 18

17Manipur 193 40 21 153 1.7 1.4 82 0.3

18Meghalaya 175 109 62 66 1.65 0.73 44 0.9

19Mizoram 127 97 76 30 1.2 0.623 52 0.6

20Nagaland 164 66 40 98 1.88 1.14 61 0.7

21Orissa 1723 1439 84 284 21.49 17.45 81 4

22Punjab 5561 5561 100 0 46.59 46.59 100 0

23Rajasthan 8411 8411 100 0 58.45 54.78 94 3.7

24Sikkim 113 55 49 58 0.6 0.372 62 0.2

25Tamilnadu 3508 3508 100 0 161.33 131.25 81 30.1

26Tripura 197 197 100 0 2.28 1.84 81 0.4

27UP 8507 8507 100 0 88.06 80.38 91 7.7

28Uttaranchal 743 743 100 0 9.09 7.95 87 1.1

29WB 2347 2290 98 57 47.27 45.89 97 1.4

Total Metering 73678 70199 95 3479 1312.06 1134.27 86 177.8

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AT&C LOSS : BEST 15 TOWNS

All over the country minimum level of AT&C loss as per

data are as follows:

1. Salem

2. Tiruchengode

3. Shrilingampally

4. Ludhiana

5. Chennai

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AT&C LOSS : WORST 15 TOWNS

The highest loss were noted in north eastern region

with as high as 80%. The towns which are worst in

loss levels are as follows :

1. Jamtara

2. Garwaha

3. Latehar

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Losses in the transformers

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Losses in transformer.

Over-rated Distribution Transformers and hence their Under-Utilization

Load forecast

Energy audit

Low Voltage (less than declared voltage) Appearing atTransformers and Consumers Terminals:

As voltage level decreases it results in the increase of losses.

Reduction in the voltage level is permitted up to +/- 6%.

Load Loss and no-load loss in Transformers: Improvement in transformer design and by installing amorphous

core transformer of appropriate capacity.

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Harmonics:

For the reduction of harmonics in the distribution system

utilities either install

FILTERS

LOAD BALANCING

Losses in transformer.

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COMMERCIAL FACTOR SOLUTIONSCOMMERCIAL FACTOR SOLUTIONS

THEFT

Scientific approach

Management approach

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Scientific approach

100% Metering

Fixing Responsibilities

HVDS (High voltage distribution system)

Low voltage distribution system (LT ABC)

Underground cables

GIS System

Franchise the distribution

Automated meter reading (AMR):

Pre-Paid meters

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Management approach

Enforcement Department

Other Initiatives

Voluntary Disclosure Scheme (VDS)

Late Payment Surcharge Scheme (LPSE)

JJ Cluster Scheme

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UN-METERED POWER SUPPLY:

100% METERING OF CONSUMERS

DT METERING

DEFECTIVE METER, METER STOPPED AND METER BURNT:

ENFORCEMENT DEPARTMENT

REPAIR AND REPLACEMENT

FRANCHISE

AUTOMATED METER READING:

RELIABLE METERS METER TESTING DEPARTMENT

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WRONG READING, REDUCED COLLECTION

EFFICIENCY AND UNBILLED METERS

ELECTRONIC METERS WITH DIGITAL DISPLAY

SPOT BILLING

PRE-PAID METERS

AMR

SOFTWARE UPGRADATION

ON-LINE BILL COLLECTION

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MISUSE OF TARIFF AND UNAUTHORIZED

EXTENSION OF LOAD

ENFORCEMENT CELL

By Meter Reader Information

Periodic Checking

DATA ANALYSIS OF ELECTRONIC METER (MDI)

DATA ANALYSIS

DEFAULTER/ DELAYED PAYMENTS AND

UNACCO

UNTED

PAYMENTS:

BILLS NOT DELIVERED

CT RATIO ERRORS

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LT/HT Ratio

LT/HT lines:

I2R losses are higher in LT lines than HT lines. (Andhra Pradesh is planning to

reduce their LT/HT ratio up to 1.4:1 in 2007 like wise Haryana is trying to

reduce ratio from 1.82:1 to 1.80:1 in 2007. West Bengal has 0.98:1 andKerala has 6.14:1 (excluding EHT) LT/HT ratio)


Increase in no. of substations near to load center and construction of new HT

lines

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On LT lines technical losses are higher, but it can be reduce by implementing

HT lines up to the consumer end. Madhya Pradesh had launched it in

Bhopal, and Assam is also implemented it at pilot basis. Not even this

Maharashtra is planning to launch HVDS in its 9 major cities and many

states and utilities are in a line to implement it.

In HVDS a transformer is installed on the pole with distribution box below it

and from this distribution box consumers get supply. 12 consumers can be

connected to one distribution box.

Up to transformer 11kv line is connected and from distribution box toconsumer premises 440/230V line is connected. So as transformer are

installed near to consumer it decreases LT lines and increases HT lines.

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Increase in no. of substations near to load center and

construction of new HT lines:

Each year every utility and SEB set a target to increase their

no. of substation and no. of HT lines in order to reduce theirlosses and to improve their efficiency. By building substation

near to load center because it helps in reduction in I2R losses

and more over I2R losses are use to remain low in 132kv,

33kv,11kv bus bars.

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Merits/Demerits of low LT/HT Ratio :

Merits

Low I2R losses

Less theft problems

Efficient billing

Implementation of APDRP scheme

Efficient for rural areas

Demerits

Increases equipment cost

Maintenance expenditure increases Increases accidents chances

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Power Theft

The financial impacts of theft are

reduced income from the sale of electricity

necessity to charge more to consumers

Electricity theft can be reduced by applying solutions such as inspection

and monitoring, and in some cases restructuring power systems ownership

and regulation.

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Electricity theft can be in the form of

fraud (meter tampering)

stealing (illegal connections)

billing irregularities

Incorrect loading

unpaid bills

direct theft(hooking)

seal tampering

meter bypassing

meter burnt

unauthorized address / connection

meter not found

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Power Theft

Fraud (meter tampering)

Meter is slowed (70 -80 percent of its normal speed)

An alternate path is provided inside the meter tobypass the current

Tampered meters are burnt after an interval of timeand a fresh connection is applied

Stealing (illegal connections)

Stealing power by using incorrect type of load To take benefits of different tariff structure

Incorrect loading

Power is used above the applied load

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Power Theft

Seal tampering

meter seals are replaced with the duplicate ones

They are damaged but not easy to recognize.

Meter bypassing

The incoming is bypassed without giving path to meter formeasurement

Meter burnt

Due to heavy usage of electricity meter is burnt andaverage bill is paid (mostly in case of industrial consumers).

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Unauthorized address / connection

Connection is taken by showing duplicate documents of thesite.

Billing irregularities Bills are stopped for payment by showing the premises

locked or by bribing the meter reader .

The meter is burnt or damaged after few months.

Meter (address) not traceable New meter has been installed but address of that meter is

not traceable. In that case bill of that meter is not delivered.

Power Theft

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Unpaid bills

Heavy bills are left unpaid and a new connection is

applied with different name.

Consumer leaves the site with bills pending. Site is sold to others with left out bills

Direct theft(hooking)

A direct connection is made from the distribution network. The arrangement may be of temporarily type or permanent

type

Power Theft

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Preventing Power Theft

As a team leader various steps can be undertaken such as:

Increasing the frequency of check ups

Increasing the general awareness

Increasing penalties

Identify the theft prone areas

decreasing internal corruption

Providing good incentives

Installation of Meters in Meter Boxes Checking newly installed meters.

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RECOMMENDATIONSAND

SUGGESTIONS

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TECHNICAL SOLUTIONS

Creation of new substations in densely populated area so as toavoid overloading of equipments and improve reliability.

Erection of new feeders so that in case of outage of one may notaffect the other and to meet the future need of increasingdemand to avoid overloading of existing system. Bifurcation offeeders to limit the maximum load.

Reducing LT/HT ratio

Use of Amorphous Core Transformers and modifications.

Aerial Bunch Cables to avoid hooking of lines

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MANAGERIAL SOLUTIONS

Vigilance squads can be set up at divisional level to

check and curb the pilferage and theft of energy

and vigilance staff should be staffed with

adequate security personnel and magisterialpowers.

Severe penalties may be imposed for tampering

with the meters etc.

Special courts to be set up for the faster resolution

of theft related cases

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FINANCIAL SOLUTIONS

Increased Investment in distribution system improvement by

utilizing the investment schemes of APDRP, DRUM and large

capital flow through FDI route and portfolio management.

Investment in power system can be set up through Specialpurpose vehicle (SPVs), which bring together private sponsor

and other equity holder. Major Latin American countries

have been able to mobilize huge sector of equity and debt

financing and a large no of venture are in pipeline the

world over.

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NEW TECHNOLOGY SOLUTIONS

IT applications in the power sector have beenpiecemeal. The concept of fully automatedoperations has not yet been applied on a large

scale. This means that IT has enormous potential toimprove the sectors overall functioning, fromgeneration to transmission and distribution.

SCADA systems

Advanced metering systems Distribution transformer

Application of CIS/CRM system

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at & c

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