21st August 2003 1

Energy Efficiency in CMC Energy Efficiency in CMC Water Supply/Distribution Water Supply/Distribution

SystemSystemEM Piyasena

RA Attalage

(Sri Lanka Energy Managers Association)

21st August 2003 2

OUTLINE

ScopeWalk-through and Billing AuditDetailed AuditResultsRecommendations

21st August 2003 3

WALK-THROUGH AND BILLING AUDIT

KalatuwawaLabugamaAmbathale

Parliament GR Eliehouse GR Church-hill GRMaligakanda GR Kolonnawa GR

Battaramulla GR Dehiwala GR

BattaramullaTower

DehiwalaTower

MaharagamaTower

MahalwarawaTower

MattegodaTower

KottawaTower

KaduwelaTower

HomagamaTower

HomagamaSouth Tower

BiyagamaTower

MoragasmullaTower

KolonnawaTower

PagodaTower

MoratuwaTower

KohuwalaTower

RukmalgamaTower

General Layout up to Main Distribution Points

21st August 2003 4

WALK-THROUGH AND BILLING AUDIT………..Overall Layout

D I S T R I B U T I O N C H A M B E R ( O l d P l a n t ) D I S T R I B U T I O N C H A M B E R ( N e w P l a n t )

P R E T R E A T O R ( 1 3 . 5 M G D )

P R E T R E A T O R ( 1 3 . 5 M G D )

C E N T R I F L O C ( 1 3 . 5 M G D )

C E N T R I F L O C ( 1 3 . 5 M G D )

P U L S A T O R ( 1 3 . 5 M G D )

S U P E R P U L S A T O R

( 1 0 . 5 6 M G D )

S U P E R P U L S A T O R

( 1 0 . 5 6 M G D )

S U P E R P U L S A T O R

( 1 0 . 5 6 M G D )

S U P E R P U L S A T O R

( 1 0 . 5 6 M G D )

S E T T L E W A T E R C O L L E C T I N G C H A N N E L S E T T L E W A T E R C O L L E C T I N G C H A N N E L

1 1 9

1 2 1 0

7

8

4

5

1 2

8 7

3

6

5 3

6 4

1

2

1 3 1 5

1 4 1 6

1 7

1 8

O L D S U M P ( S . P . H )

4 2 2 0 m 3

K U B O T A S U M P

9 1 0 0 m 3

N E W P L A N T S U M P

2 x 3 3 0 0 m 3

4 2 2 0 m 3

K E L A N I R I V E R

E L I E H O U S E R E S E R V O I R

M A L I G A K A N D A

R E S E R V O I R

C H U R C H I L L R E S E R V O I R

K O L O N N A W A

R E S E R V O I R

J U B I L E E

R E S E R V O I R

M O R A T U W A R E S E R V O I R

4 6 0 0 m 3

P A N A D U R A R E S E R V O I R

2 6 0 0 m 3

D E H I W A L A R E S E R V O I R

1 7 7 0 0 m 3

2 3 4 1 2 3 A 5 B C 1

2

2 1 3 1 4 3 2 4 1

1 2 3 4 1 3 2

3 2

1 2 1

1

2

3

O 2 0

N 3 0 O 2 0

D 2 0 N 3 5

21st August 2003 5

CMC Distribution System

Dehiwala

Maligakanda

Jubilee

Eliehouse

Total = 62.5 MGD

LABUGAMA

KALATUWAWA

AMBATELE

Greater Colombo others

Total = 67.5 MGD

15 MGD

8 MGD

107 MGD

WALK-THROUGH AND BILLING AUDIT…contd

21st August 2003 6

Percentage Distribution to Each Reservoir

Jubilee24%

Kolonnawa7%

Dehiwala22%

Maligakanda16%

Churchill15%

Eliehouse-27%

Eliehouse-19%

Total Average Production is 109 MGD (20588 m3/hr)

WALK-THROUGH AND BILLING AUDIT…Contd

Share of Distribution of Each Reservoir

21st August 2003 7

Composition of Monthly Production Cost – Ambathale Treatment Plant

6%

84%

7% 2%

1%

Personal

Electricity

Chemical

Repair

Admin&Security

WALK-THROUGH AND BILLING AUDIT…Contd

21st August 2003 8

Electricity Consumption Variation

Monthly Production Vs Elec. Consumption

13.0

13.5

14.0

14.5

15.0

15.5

16.0

4.0 4.5 5.0 5.5 6.0

Elec. Consumption (GWh)

Pro

du

ctio

n (

Mill

ion

m3)

WALK-THROUGH AND BILLING AUDIT…contd

21st August 2003 9

Monthly Electricity Consumption

6.0

4.95.2

4.34.8

5.24.8

5.5

4.6 4.7 4.8

5.7

0.41 0.33 0.38 0.31 0.34 0.35 0.32 0.42 0.31 0.32 0.31 0.390.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

Jul-01 Aug-01

Sep-01

Oct-01

Nov-01

Dec-01

Jan-02

Feb-02

Mar-02

Apr-02

May-02

Jun-02

Month

Con

sum

ptio

n

(MWh) (kWh/m^3)

WALK-THROUGH AND BILLING AUDIT…Contd…

21st August 2003 10

Cost of Electricity

39.60

32.2434.64

28.7732.19 34.09

31.6036.53

30.76 31.20

38.99

48.98

2.69 2.20 2.51 2.06 2.26 2.28 2.09 2.73 2.05 2.17 2.56 3.370.00

10.00

20.00

30.00

40.00

50.00

60.00

Jul-01 Aug-01 Sep-01 Oct-01 Nov-01 Dec-01 Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02

Month

Cost

(Rs.

Mill

ion

), (R

s. /m

^3)

Electricity Cost Cost per m 3̂

WALK-THROUGH AND BILLING AUDIT…Contd…

21st August 2003 11

DETAILED AUDIT

Three major pump sets – Maligakanda , Church Hill and New intake Electricity Input, pump head, flow rate and

pump speed for parallel and single operation, Pump performance evaluation Power factor measurements

Optimization of clarifiers On-line calibration of flow meters

Preliminary Investigation

21st August 2003 12

Expected and Measured EfficienciesPumps which are Efficiency Expected Efficiency Measuredrunning together Acording to the Curve

New Intake to New PlantA, C, 5 Effi > 80% A = 46%

C = 39% 5 = 68%

A, 5 Effi > 85% A = 55% 5 = 63%

A, C Effi > 85% A = 57% C = 43%

New Intake to Old Plant1,3 -- 1 = 70%

3 = 68% 3 Effi > 90% 3 = 69%

Maligakanda pumps Ambathale Treatement PlantM-1, M-2 Effi > 80% M-1 = 69%

M-2 = 68% M-1 Effi > 70% M-1 = 57% M-2 Effi > 70% M-2 = 59%

Churchill pumps Ambathale Treatement PlantC-1, C-2, C-3 Effi > 75% C-1 = 69%

C-2 = 67% C-3 = 69%

C-1 Effi > 80% C-1 = 73% C-2 Effi > 80% C-2 = 75% C-3 Effi > 80% C-3 = 69%

DETAILED AUDIT…contd

21st August 2003 13

Power Factor Measurementex:New Intake to Ambathale Treatment Plant

Pump ID Voltage (V) Current (A) Power (kW) Power factor

Pump A 385.9 635.4 351.6 0.82

Pump C 385.6 672.3 371.1 0.82

Pump 1 402.0 278.9 156.0 0.80

Pump 2 406.5 334.5 187.0 0.79

Pump 3 404.2 339.8 189.6 0.79

Pump 5 401.9 274.7 158.8 0.83

DETAILED AUDIT…contd

21st August 2003 14

Low power factors at loadsOverall operating efficiencies are lower than

the expected.Large variation in energy intensities of

pumping.Water loss due to back wash, sludge drainage

& lab testing is around 7 MGD.NRW is around 50% in Colombo city

distribution system

PRELIMINARY RESULTS

RESULTS

21st August 2003 15

Optimizing energy intensity of pumpingRange of monthly production varies from 101.17 –

111.27 MGDRange of monthly energy consumption 4.3 – 6.0

GWhMonthly specific energy consumptions vary from

0.31-0.42 GWh/m3

Same production has distinctly different energy consumption values

Enhance clarification during high turbidity periodAnnual savings of 2 GWh, Rs. 16.7 millionCost involved Rs.16 million

RESULTS…contd

21st August 2003 16

Power Factor improvement

Low Power Factors (0.79 – 0.83) were found in the new intake

Potential monthly max. demand reduction by improving power factor to 0.95 is 1.52 MVA

Total monthly savings is Rs.0.6 millionSimple payback is 2.4 months

RESULTS…contd

21st August 2003 17

Improving overall efficiency of pumping units.

Measured operating overall efficiencies of all the pumps (ranging 40% to 75%)

Improving overall efficienciesChurch-hill

Annual savings of 0.94GWh, Rs.7.5 million Simple payback for impeller sizing, 08 monthsSimple payback for pump replacement, 07years

RESULTS…contd

21st August 2003 18

Improving overall efficiency of pumping units.

Improving overall efficienciesMaligakanda

Annual savings of 0.90 GWh, Rs.7.2 million Simple payback for impeller sizing, 06 monthsSimple payback for pump replacement, 5.5years

Extrapolation…..Ambatale PlantAnnual savings of 6.3 GWh

(Comparison monthly mean consumption of 5 GWh)

RESULTS…contd

21st August 2003 19

On-site calibration flow meters.

Verification by on-line calibrationFirst results show that flow meter

readings overestimate by 15%Study to be continued for

confirmation.If so, estimated saving potentials will

be much higher with low NRW losses.

RESULTS…contd

21st August 2003 20

Water consumption reduction by end users

End user survey through a questionnaire Simple statistical analysis carried outEstimated end-use water saving potential,

17%.Detailed study is required to extrapolate the

results to the CMC distribution areas.Identify cost effective, efficient end use

methods/strategies with the view to conserve

RESULTS…contd

21st August 2003 21

RECOMMENDATIONS Low cost no cost options

Enhance clarification. Further investigation of the fluctuation of energy per unit product is necessary.

Continue the calibration work to confirm results.Water consumption reduction by end users.

Medium cost optionsPower factor improvementFurther investigation of NRW

High cost optionsReplacement of low efficient pumps with new pumpsIn-situ electricity generation? (study)Diesel Engine driven pumps? (study)

21st August 2003 22

Thank You

Co-operation and assistance extended by the National Water Supply and Drainage Board is

greatly acknowledged.