Promotion of Energy Conservation Activities
in Factories (Electricity)

Kokichi TAKEDA
Energy Conservation Center, JapanIn Lao PDR
October, 2006
ECCJ1

1. Promotion ofEnergy Conservation Activity
2. Viewpoint of Power-saving
3．Methods of power-savingof major electric facilities
4. Power-saving Examplesof Cement Process in Japan2

1. Promotion of Energy Conservation Activity
1.1 Significance ofEnergy Conservation

Energy Conservation Activity
has contributed to Cost Down of each factory
moreover, Improvement of Cost and “SEC”(“SEC” is Specific Energy Consumption and defined asenergy conservation divided by production)＆Energy Conservation Activity
has contributed to Reduction of the global warming
・Estimation in oil：0.252 [kL／MWh]・Estimation in CO2：0.555 [t-CO2／MWh]
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1.2 Control of Energy Conservation① Establish organization control② Set the goal・Management has to keep consciousnessof employees.
・All staffs have to be involved in the project.

Criteria of goal setting : operation, inspection,maintenance, and budget③ Grasp the circumstances

Setup of measuring and recording devices④ Perform⑤ Make an improvement plan

⑦ Assess the results

Performance of energy conservation
1. Small group activity
2. day-to-day business of staff
3. General development⑥ Implement revised plans

Repeat PDCA cycle of energy management
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1.3 3 steps for Promotion of Energy Conservation
1st step: Reinforce energy management and increase
efficiency of operations
・ Low cost・ To avoid wastefulness
・ To optimize use of existing equipment
・ To make all staff involved
・ To avoid unscheduled stop of operations

2nd step: Modify and/or add equipment
・ Medium cost
・ Modification and/or addition of equipment ( It will be ineffective
if main facilities are renewed or replaced)・ Introduction of energy-saving devices

3rd step: Introduce new processes and high efficiency
equipment
・ High cost・ Long-term investment
・ It is necessary to develop and introduce new processes.
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1.4 Work Flow of Energy Conservation Activity in Factory＜Incentive of activities bymanagement in the factory＞
・To set a goal
・To select objectives
・To set a deadline＜Establish an organizational system foractivities＞
・ To organize a team for activities･ To organize a team for measurement

・To make budget for energy conservation
measures, modification of equipment
・To estimate effects on energy
conservation measures･To transfer ideas to other equipment

ECCJ＜1st STEP： Prepare for activities＞
・To collect related information
・To make action plan for the activities
・To analyze existing processes
・To analyze energy consumption＜2nd STEP： Extract and winnow ideas
for energy conservation＞
・To collect energy conservation ideas by
1. check list
2. brainstorming
3. recruiting
・To winnow energy conservation ideas＜3rd STEP： Select measuresfor energy conservation ＞
・ To assess energy conservation measures(effect on energy conservation andinvestment)
・ To select plans for energy conservation
61.5 Energy Audit
To fill out questionnaire about situations of energy
conservation in a factory
Brief
Audit

Hearing from staffs in a factory
Inspection of a factory
・Identification of basic problems in a factory･Proposal for overcoming (probability, latency and directions)

Detailed
Audit

Cooperation with specialists in energy conservation
Investigation in detail: understanding of present situation,
making guideline, and assessment of results･ Identification of quantitative issues on energy usage･ Proposal of definite guidelines (effect of investment
for equipment and control)

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1. Promotion ofEnergy Conservation Activity
2. Viewpoint of Power-saving
3．Methods of power-savingof major electric facilities
4. Power-saving Examplesof Cement Process in Japan8

2. Viewpoint of Power-saving
2.1 Distribution of electricity : efficiency of facilities
Receiving, transforming and electric power distributing
equipment (transformer, cable and others)< 95〜97% >pump, fan･blower

valve, damper(efficiency changes withvalve/damper opening)< 60〜85% > <20〜100% >Motor, VVVF, and others< > : efficiency of facilities（It is different by facilities)

Piping, duct

Excessive supply(Ｑ,Ｐ)(-α) : piping loss (efficiency changes
with load factor )and others）< 70〜95% >(8〜78）(40〜78）
motor

load

pump

(66〜92 ）(95〜97）load

transformer
VVVF

motor

pump

nozzle( ): available power at eachfacility when power supply
is 100load(100)PowerSupply

Maintransformer

transformer

motor

Ｆａｎnozzle

nozzletransformer

motor

ＡＣ

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☆ Selection of Equipment which are Subject to Energy
Audit from a Viewpoint of Consumption and Efficiency★Categorization of Power Consumption (or related power losses)
Essential Energy
Consumption

Energy used for
non-effective operation

Wasted Energy

Improvement ofoperation and process

Reduction

Reduction

LossHigh efficiency★Point of Selection of equipment for Energy Conservation① Equipment (electric motor, transformer, etc）is subject to be audited
only when they are established or renewed.
It is difficult to renew electric motor, transformer, and cables except for lighting facility forenergy conservation, because these equipment contribute too little to operating efficiency
and are too expensive to increase efficiency.

② Main target is motor-powered equipment for energy conservation.
Energy conservation may be expected by avoiding wastefulness and improving
efficiency of motor-powered equipment (pump, fan, blower, air-compressor, etc)
because these equipment represent a large portion of energy consumption.
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Power Consumption

2.2 Breakdown of Energy Consumption by its Usage

APower Consumption

AB

BCCC

D
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Working hour

Working hour

9ABCD101112 13Hour1415161718

Variable part
A: to be proportional to production
B: to keep product plants
Fixed part
C: to start up or shut down lines
D: to keep utility plants
11Constant

NowP.CPower consumption☆ 3 Viewpoints of Energy Conservation Activity

AB
CD

Variable part
①Production-up
SEC-down
Fixed part

CProduction Increase
Saving energy
E. S②Slim eachconsumption
V.PA
P.C

A
P.C

B

D

Production③Transfer fixed
into variable part

B→A
C→A
D→AA

F.P

V. PBCD

F. P
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ProductionProduction

☆ Viewpoint of Energy Conservation Activity
for Reducing Fixed Part of “ B, C and D① Is a machine paused during a resting period in intermittent operation?
･ To pause a coupling of product lines･ To make an automatic ON or OFF② Is a capacity of equipment too large against requirement?
･ To introduce an inverter for pressure regulation in place of valve and damper･ To scale down a capacity③ Is a fluctuation of workloads properly regulated?
･ Automatic control of workloads･ Variable flow control④ Are inspection and maintenance definitely carried out?
･ Guideline on leakage prevention of air and water･ Prevention of pressure loss with cleaning filters etc･ Inspection with regular dismantlement of devices

Awareness in operators and maintenance staff on energy conservation
is of primary importance.
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1. Promotion ofEnergy Conservation Activity
2. Viewpoint of Power-saving
3．Methods of power-savingof major electric facilities
4. Power-saving Examplesof Cement Process in Japan
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3．Methods of power-saving of major electric facilities
3.1 Pumps, Fans, and Blowers
Viewpoint of power-saving

Examples regarding methods of power-savinga) Reduction of flow rateAnti-leak measure of air and water, prevention of excessive use,etcb) Reduction of pressure

Reduction of operating pressure, Reduction of pressure loss
( filter, etc)c) Reduction ofexcessive specification(reduction to reasonable level)

・To replace to small capacity or machine of less pressure loss
・To change impeller, to cut down impeller diameter,
and to decrease stages of rotor impeller
・To change a rotating speed (pole change or pulley, inverter)d) Addition ofvariable flow control
and multi-unit control

・ Addition of multi-unit control system
・ Selection of big and/or small machines
・ Addition of variable flow control (pole change, pulley, fluid
coupling, vane control, inverter)e) Replace tohigh efficiency machine・ To replace to high efficiency machinef) Pause at a resting timein intermittent load・ To replace to motor of high frequency start type・ Addition of soft starter with inverter
・ Addition of fluid coupling
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☆ Multi-unit Control in Pumps and Blowers
Figure shown below is a comparison of pump efficiency (100%, 80%, or 50% ofcapacity).
(1)Selection of properly-sized pump
Efficiency of pump with 80% capacity is about 10% better than that of a pumpwith 100% capacity operated at 70% load.
(2)Multi-unit control in pumps
Efficiency of pump with 50% capacity is about 35% better than that of a pumpwith 100% capacity operated at 40% load.
Introduction of multiple small pumps instead of one big pump, and control of anumber of operating pumps,
soポンプの容量選定と台数制御
called multi-unit control, lead to energy conservation.
図3.1.2efficiency of pumpMultiple pumps or one big pump
100%
80%
60%
100%100%capacity
100%容量のポ80% capacity
ンプ
80%容量のポン
50% capacityプ

40%
20%0%0%ECCJ

20%

40%60%

80%

100% 120%flow ratio

☆ Power-saving by Speed Control (1)Resistance curve at 80% flowwith valve control
PipelineB’resistance curve

Delivery pressure(Total pump head)

HB’

HA

Energy saving

HvA

Q-H curveat rated speed

HBR2
HS

Q-H curve at aspeed of 80%

B

R1

Net pump head
QBECCJ

QＡ

Flow17

☆ Power-saving by Speed Control (2)System2：
When static pressure (P20) of supplier is higher thanthat (P10) of recipient, both a difference of pressure
between supplier and recipient and a loss of pressurein piping are compensated by pump.
(1) Pressure and flow reach P2r and Q2r at 100% of
revolution without throttling valves.
(2) Effect on energy saving is less than System1, because
static pressure of recipient is higher than that of
System1.

v ol ution

90 %2of reSy
stem

Pressure(1) Pressure and flow reach P1r and Q1r at 100% of
revolution without throttling valves.
(2) If valves are not throttled, flow cannot be decreased
from Q1r to Qa. However, if pressure is reduced to P1by valve throttling, flow will decrease to Qa.
(3) If pressure and flow decrease to P1 and Qa by
reducing revolution, it is more efficient to saveenergy than by valve throttling.
(4) Required brake power is shown in the figure asshown below.

Q-H curve
100%

Pa

80 %

P2r
P1r

P2

70 %
60 %

P1

50 %

P20

P10System

１flow

Qa

Brake power

System1：
When static pressure of recipient is the same as thatof supplier, loss of pressure in piping iscompensated by pump.

Pump revolution
vs brake power100%ofreluvotio

n%
90%
80%
7060 %50 %Qa Q2r Q1r flow
ECCJ3.2 Air Compressor<Compressed air system>
0.2MPaViewpoint ofPower-saving

Examples regarding
Methods of Power-saving

Review whether spec.
is too large or not･Optimization of spec. for user
(on/off control, conversion to low
pressure air by blower)

Reductionof air leak･Measures of air leak･Detector for air leak (valve, flange,others)

Actuatornozzle0.4MPaHigh pressurecompressor
or booster valve

Reduction ofpressure loss
Division byuse pressure･Reduction of pressure loss inpiping and reducing valve･Addition of high pressurecompressor or booster valve

Addition ofhigh efficient
control systemthat adapts toload fluctuation･Control of multi-unit control･Addition of variable flow control(inverter, IGV, others)･Integration of compressors

0.6MPaHeader

RTAir Compressors
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Selection of highefficient machine
Pause at a resting
period･Selection of inverter system･Small capacity, low pressure･Addition of automatic
driving/pause function,others19

(Examples)
Comparison of electricity consumption of the compressor
at variable capacity system
100①：system to adjust
suction valve①, ②
consumption electricity[%]

80

①60

②②：system to adjust
suction valve
and air purge③③：system to change
air load/unload
by air purge④40④：inverter system
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204060Quantity of use air[%]

80

10020

3.3 Lighting apparatus
Viewpoint of Power-saving

Examples regarding methods of power-saving

Choice of high efficiency light sources

Choice of high efficiency lamp such as sodium lamp
Choice of Hf fluorescent lamp utilizing inverter
Choice of low loss type stabilizer

Reduction of illumination

Adequacy of lighting standards in workshop
Reduction of whole illumination and use of part illumination
Dimming of lighting through proper lighting control

Reduction of illumination object

Review and reduction of place needing illumination

Choice of high efficiency lamps

Choice of high efficiency lamp, floodlight beams

Improvement of illumination rate

Consideration such as reflection efficiency to lighted
location

Improvement of maintenance rate

Periodical cleaning of lamp
Appropriate exchange of lamps

Reduction of lighting time

Close lights out
Extinguishing of lighting through proper lighting control

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Energy Consumption of Lighting Apparatus
Powerconsumption[kWh]Powerconsumption
per apparatus[kW]

Lightingtime[h]Number ofapparatus
Ｎ [set]

E×A
N =Φ×U×M

N: Number of lighting apparatus
A: Room space [m2]installed
U: Utilization factor
E: Average luminance on working
M: Maintenance factor
place [LX]
Lighting standards in workshop
Φ: Luminous flux perin JAPAN : ＪＩＳ Ｚ９１１０
lighting apparatus [lm]
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Replace with more efficient light
40w×2 tubes
with C &C stabilizer

Light flux

36w×2 tubeswith C &C stabilizer

Light flux

32w×2 tubes
with Inv. stabilizer

Reflection plate

Light flux
Original

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Replace Hf tube

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3.5 Electric Power Distribution System

VCTmaintransformer

Viewpoint ofpower-saving

Examples regarding
methods of power-saving

Selection ofhigh efficiency
apparatus

Selection of high efficiency
transformer☆

Improvementof power factor

Addition of condenser
for improvement of power
factor ☆
Selection of high power
factor apparatus ☆

transformer
apparatuswith pause
at a restingtime

StaticCondenser

load
ECCJloadM

Integration and haltof light-load transformers
Pause of fans for transformers
when transformers are loaded
lightly and/or not heated☆：Consider when facilities will be replacedor equipment will be newly installed24

1. Promotion ofEnergy Conservation Activity
2. Viewpoint of Power-saving
3．Methods of power-savingof major electric facilities
4. Power-saving Examplesof Cement Process in Japan
25

４．Power-saving Examplesof Cement Process in Japan
4.1 Power saving on Clinker-cooling-FanEPBoiler(Heat recovery) (Elector-staticprecipitator)
Clinker cooler

F1 F2 F3 F4 F5 F6Cooler fansFDuctDuctECCJExhaustclinker coolingsystem

Gas velocity is too high:33m/s
Pressure loss is large:150mmAq

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Measurement Data
Pressure (mmAq)

Clinker Cooler③⑦D5F4 ⑥D4⑤②F5Position

Pressure

④-270

①-122

⑤-280

②-135

⑥-250

③+260

⑦+430

Flow(m3/min)Damperopening

F4

3,750

78%

F52,800

100%①④Gas Data at Position #1

Fan data

Temperature(℃) 115
Velocity (m/s)

Around 33

Flow(m3/min)

6,550

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Improvement Measures
Clinker Cooler③⑦D5F4 ⑥②D4⑤

1. Place a new duct to reduce gas velocity
Damper-opening:F4:55%, F5:45%
2. Fan-runner cutting

F5①④⑧

Runner Diameter (mm)

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Original

After cutting

Cut-ratio

F4

1,568

1,506

4.0%

F5

1,348

1,276

5.3%

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Evaluation
1.Pressure (mmAq)
Position Pressure④-270 to -97①-122 to -60⑤-280 to -110②-135 to -70⑥-250 to -203

③260 to +256⑦

430 to +388

Position Speed(m/s)
33 to 18.0⑧-56

3.Damper opening

2.Gas flow①⑧

17.5Flow(m3/min)
3,565

Lay Duct

Runner-cut

F457%

80%

F545%100%

3,104

4.Power consumption of Fans (kW)ECCJ

BeforeNew duct

Runner-cut

Saving

F4550525489

61F52542672054929

4.2 Power-saving on Cooling Water System
Cooling water circulation in finishing section
Supply water

Water pool
Tank for water circulation

Tank for water supplyCooling
Separator line

P1

Mill line

P2

Other processes
P1:#1 Supply water pump
P2:#2 Supply water pump
P3:Recovery water pump

Recovery water

Tank for recovery water
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P330

Inverter control and Management system
Level indicating
controller

Level sensor

LIC

Tank for water supply

Free from overflow loss

Cooling
Separator line

P1

Mill line

P2

Recovery waterLe
Hz Console
Hz0〜50Hz
VVVF

Managementsystem

From valve control
to INV control
0〜50HzTank for recovery water

P3

VVVF

From On/Off control to INV control
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Evaluation
1.Water Saving
Before

18t/h

After

10t/h

Saving8t/h

2. Energy Saving

(kW)
P1

P2

P3

total

Power Consumption

3.7

1111

25.7

Saving―72

9.0

3. Conclusion

Saving Water is Saving PowerThe End
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Thank you!
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