Moriya, M.

Shima,K.

Shimoda,Y.

Takada,O

Takase,T.

Texas A&M University

Commissioning Process and 
Operational Improvements in the 
District Heating and Cooling Plant 
Tomoaki TAKASE, Mitsubishi Jisho Sekkei Inc., 
Osamu TAKADA, Mitsubishi Jisho Sekkei Inc., 
Kiyoshi SHIMA, Obayashi Corporation 
Mitsuru MORIYA, Takasago Thermal Engineering Co., Ltd
Yoshiyuki SHIMODA , Osaka University 
APCBC presentation in ICEBO
(Asia Pacific Conference on Building Commissioning)
Sept. 2014, Beijing, China
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
2(1) To achieve the top-class energy 
efficiency among the DHC plants in 
Japan
(2) To evaluate the energy saving effects 
of commissioning and operational 
improvements
TARGETS ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
3• ABOUT THE DHC PLANT
• EXAMPLES OF COMMISSIONING AND 
OPERATIONAL IMPROVEMENTS
• RESULTS AND CONCLUSION
OUTLINE ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
4• ABOUT THE DHC PLANT
• EXAMPLES OF COMMISSIONING AND 
OPERATIONAL IMPROVEMENTS
• RESULTS AND CONCLUSION
OUTLINE ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
5ABOUT THE DHC PLANT
DHC plant in Nishi-Umeda district of Osaka, Japan
The 2nd  Plant
The 1st  Plant
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
Heat supply Schematic Diagram 6
Total Supply Area ：approx.200,000㎡
The plant supplies both chilled and hot water 
to commercial facilities, offices, theaters, and 
the train station, etc.
AR1-5 X 5
TR1,2 X 2
TR3,4 X 2
IST X 2
The 2nd Plant
Station
Retail 
Shop
Department 
Store
Fit Theater
Office
Electric 
Room
Machine 
Room (13F)
1st 
Plant
Optical Cable
（Monitoring）
BTR1,2 X 2
ABOUT THE DHC PLANT
Comme
rcial 
62%
Office
20%
Station
6%
Theater
4%
Others
8%
Ration of Heat Supply Area
Commercial
62%
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
Capacity of cold heat generators： 36,871 kW （10,500RT）
Capacity of hot heat generators  ： 15,430 kW
Symbol heat generator Capacity Number
AR1～5
Gas-fired Absorption Water Chiller Boiler
(= Absorption Chiller)
Cooling Capacity : 3,516kW (1,000RT)
5
Heating Capacity : 2,900kW
TR1,2 Centrifugal Chiller (Constant Speed ) Cooling Capacity : 3,516kW (1,000RT) 2
TR3,4 Inverter Centrifugal Chiller Cooling Capacity : 1,758kW (500RT) 2
BTR1,2 Centrifugal Chiller for Ice Storage
Cooling Capacity : 1,571kW (447RT)
2
Ice Making Capacity : 1297kW (369RT)
IST1,2 Ice Storage Tank
Capacity of Thermal Storage :11,603kWh 
(3,300RTh) 2
BO1,2 Hot Water Boiler Heating Capacity : 465kW 2
7
ABOUT THE DHC PLANT
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
8OUTLINE
• ABOUT THE DHC PLANT
• EXAMPLES OF COMMISSIONING AND 
OPERATIONAL IMPROVEMENTS
• RESULTS AND CONCLUSION
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
■Commissioning Schedule
■ Commissioning Team
9
Adviser
Plant Owner , 
Operator
Commissioning 
Authority
Designer
Supervisor
Builder
Mitsubishi Jisho Sekkei Inc., 
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
2008 2009 2010 2011 2012 2013
System Design
Cunstructing
Commissioning
Operation Improvement
April : Completion
May : Grand Opening
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
 Verification of the designed performance 
of the systems and the equipment through 
the commissioning process
 Operational improvements in efficiency, 
based on the result of the commissioning
10
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
POLICY  
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
1. Search for the most suitable operation method
in consideration of efficiency and running cost
2. Commissioning and optimizing the number of
operating inverter centrifugal chillers and the
start/stop timing
3. Commissioning and optimizing the flow control
on the cooling water
11
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Examples of commissioning and operational improvements
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
 Regardless of cooling water temperature, theinverter centrifugal 
chiller is more efficient than other heat generators.
 As cooling water temperature decreases, the inverter centrifugal 
chiller increases its efficiency, compared to the absorption chiller.
0.50
1.50
2.50
40% 60% 80% 100%
S
y
st
em
 C
O
P
Cooling Water Temperature : 32℃
Inverter Centrifugal Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
0.50
1.50
2.50
40% 60% 80% 100%
S
y
st
em
 C
O
P
Cooling Water Temperature : 24℃
Inverter Centrifugal Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
12
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Load Factor[％] Load Factor[％]
Search for the most suitable operation method in consideration of efficiency and running cost
Relations of load factor/cooling water temperature and system COP
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
 In terms of  running costs (heart unit price), the electric 
system (centrifugal chiller) is more advantageous than the 
gas system (absorption chiller) 
 In case of low load period in summer, the ice storage system 
is more advantageous than others in running costs
Relations of load factor/cooling water temperature and running cost 
0%
20%
40%
60%
80%
100%
120%
140%
160%
180%
200%
40% 60% 80% 100%
H
e
a
t 
U
n
it
 P
ri
ce
 R
a
ti
o
[%
]
cooling water temperature : 24℃
Inverter Centrifugal 
Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
0%
20%
40%
60%
80%
100%
120%
140%
160%
180%
200%
40% 60% 80% 100%
H
ea
t 
U
n
it
 P
ri
ce
 R
a
ti
o
[%
]
cooling water temperature : 32℃
Inverter Centrifugal 
Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
◆Heat Unit Price Ratio ： 100% = Heat unit price of  centrifugal chiller with cooling water temperature
at 32℃ and  Load factor 100%)
13
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Load Factor[％] Load Factor[％]
Search for the most suitable operation method in consideration of efficiency and running cost
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
Constant speed 
centrifugal chiller
Ice storage
（Ice Melting Mode)
Absorption chiller
Inverter centrifugal chiller
14
Operation order of the cold heat generators
Operation order (from first to last)
Inverter centrifugal chiller→Constant speed centrifugal chiller
→Absorption chiller →Ice storage
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Search for the most suitable operation method in consideration of efficiency and running cost
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
15
As the cooling water temperature decreases, the system COP 
improves by adding the second chiller earlier.
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Commissioning and optimizing the number of operating inverter centrifugal chillers
and the start/stop timing
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0 200 400 600 800 1000 1200
12℃
16℃
20℃
24℃
28℃
32℃
500RT
Two Chillers Operation
(Solid Line)
Cooling Water 
temperature
One Chiller Operation
(Dotted Line)
Two chillers operation 
is more efficient from 
this point
‣
Cooling Outputs(RT)
S
y
st
em
 C
O
P
Efficient operation by controlling number of operated  chillers (simulation)
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
16
System COP improved with the 2nd inverter centrifugal chiller starting earlier
Efficient operation by controlling number of operated  chillers
(measured data)
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Commissioning and optimizing the number of operating inverter centrifugal chillers
and the start/stop timing
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0 200 400 600 800 1000 1200
S
y
st
em
 C
O
P
Cooling Outputs(Total of two chillers)[RT]
Improvement of System COP
500RT
Nov.2011 - Mar.2012  Normal Operation
Nov.2012 - Mar.2013  Earlier Start of Second Chiller
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
17
Unit COP based on cooling water inlet/outlet temperature
The unit COP data published from 
manufacturers are based on the inlet 
temperature and the constant flow system
In case of the variable cooling water flow system, 
The unit COP is affected more by the outlet water 
temperature than by the inlet water temperature
Changes in the unit COP of the inverter centrifugal chiller
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
0 20 40 60 80 100 120
U
n
it
 C
O
P
Load Factor[%]
outlet 32℃
outlet 36℃
outlet 40℃
outlet 20℃
outlet 28℃
★outlet 24℃
Based on outlet temperature of cooling water
16 - 24℃
（Cooling Water Flow Rate : 50%）
16～24℃
（Cooling Water Flow Rate : 100%）
16 - 24℃
（Cooling Water Flow Rate : 100%）
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
0 20 40 60 80 100 120
U
n
it
 C
O
P
 
★
inlet 24℃
inlet 28℃
inlet 32℃
inlet 16℃
inlet 12℃
inlet 20℃
Load Factor[%]
Based on inlet temperature of cooling water
16 - 24℃
（Cooling Water Flow Rate : 50%）
16 - 24℃
（Cooling Water Flow Rate : 100%）
Commissioning and optimizing the flow control on the cooling water
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
18
Energy simulation
In case of the variable cooling water flow system, the cooling 
water outlet temperature should be a parameter of control
Comparison between the variable cooling water flow 
system and the constant system by simulation 
Based on the simulation, except for the mid summer (July 
and August), the constant cooling water flow system is more 
energy saving than the variable system in this plant
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Commissioning and optimizing the flow control on the cooling water
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
Change in energy consumption by changing 
the water flow control （measured data）
19
The constant cooling water flow control has been applied
for the inverter centrifugal chillers from the second year
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
11,000
12,000
13,000
2012/10/072012/10/28 2012/11/18 2012/12/09 2012/12/30 2/24
｜
3/2
C
o
n
su
m
ed
 e
le
c
tr
ic
it
y
 p
er
 h
ea
t 
u
n
it
 [
k
W
h
/G
J
]
Variable water
flow control
Cooling tower fun
Chilled water pump
Cooling water pump
Chiller
Constant water
flow control
2/10
｜
2/16
1/27
｜
2/2
1/13
｜
1/19
12/30
｜
1/5
12/16
｜
12/22
12/2
｜
12/8
11/ 8
｜
11/24
11/4
｜
11/10
10/21
｜
10/27
0/7
｜
10/13
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Commissioning and optimizing the flow control on the cooling water
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
20
OUTLINE
• ABOUT THE DHC PLANT
• EXAMPLES OF COMMISSIONING AND 
OPERATIONAL IMPROVEMENTS
• RESULTS AND CONCLUSION
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
21
Annual average plant system COP of 1.35 has 
been achieved at the 3rd year after operation start
Plant System COP= 
𝑄
𝐺𝑃+𝐸×𝑒𝑝
Definition of the plant System COP Q：Total heat supply (chilled water and hot water)[KJ]
Gp：Gas-fired Absorption Water Chiller Boiler [KJ]
E：Total electricity consumption of the plant[kWh]
ep：Conversion factor to primary energy[9,760kJ/kWh]
RESULTS AND CONCLUSION
COP1.35 is the top-class efficiency in Japan
This Plant
1st year
1.19
2nd  year
1.29
3rd year
1.35
The Plant System COP of all the DHC plants in Japan of 2012
0 .0
0 .2
0 .4
0 .6
0 .8
1 .0
1 .2
1 .4
シ
ス
テ
ム
Ｃ
Ｏ
Ｐ
全電気D H C
コージェネ+D H C
ごみ排熱利用
電気ガス併用
データ出典： 熱供給事業便覧平成2 4年版
( )年月は供給開始を示す
Average value of all the plants COP 0.76
Reference : Japan Heat Supply Business Association Hand book(2013)
S
y
st
em
 C
O
P
Design target of  this plant COP 1.2
Achieved value at the 3rd year after operation start COP 1.351.4
.
.
.
.
0.4
0
0.2
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Op rations, Beijing, China, September 14-17, 2014
22
(1) Top-class energy efficiency of DHC plants 
in Japan have been achieved by applying 
the commissioning process
(2) In order to achieve assured energy 
savings, the commissioning process and 
operational improvements based on its 
results are very important
RESULTS AND CONCLUSION
CONCLUSION
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
23
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Search for the most suitable operation method in consideration of efficiency and running cost
0.50
1.50
2.50
40% 60% 80% 100%
S
y
st
em
 C
O
P
Cooling Water Temperature : 32℃
Inverter Centrifugal Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
Load Factor[％]
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
24
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Search for the most suitable operation method in consideration of efficiency and running cost
0.50
1.50
2.50
40% 60% 80% 100%
S
y
st
em
 C
O
P
Cooling Water Temperature : 24℃
Inverter Centrifugal Chiller
Centrifugal Chiller
Direct Cooling Mode
(Ice Storage System)
Ice Melting Mode
(Ice Storage System)
Absorption Chiller
Load Factor[％]
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
25
Ice storage
EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS
Search for the most suitable operation method in consideration of efficiency and running cost
Operation order 
(from first to last)
Absorption chiller
Constant speed 
centrifugal chiller
Inverter centrifugal chiller
Constant speed 
centrifugal chiller
Ice storage
（Ice Melting Mode)
Absorption chiller
Inverter centrifugal chiller
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014
26
Definition of the Plant System COP
Q ：Total heat supply (chilled water and hot water)[KJ]
Gp：Gas-fired Absorption Water Chiller Boiler [KJ]
E ：Total electricity consumption of the plant[kWh]
Ep ：Conversion factor to primary energy[9,760kJ/kWh]
Plant System COP= 
ESL-IC-14-09-25
Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014


English

Commissioning Process and Operational Improvement in the District Heating and Cooling-APCBC

Texas A&amp;M Repository

Commissioning Process and Operational Improvements in the District Heating and Cooling Plant Tomoaki TAKASE, Mitsubishi Jisho Sekkei Inc., Osamu TAKADA, Mitsubishi Jisho Sekkei Inc., Kiyoshi SHIMA, Obayashi Corporation Mitsuru MORIYA, Takasago Thermal Engineering Co., LtdYoshiyuki SHIMODA , Osaka University APCBC presentation in ICEBO(Asia Pacific Conference on Building Commissioning)Sept. 2014, Beijing, ChinaESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20142(1) To achieve the top-class energy efficiency among the DHC plants in Japan(2) To evaluate the energy saving effects of commissioning and operational improvementsTARGETS ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20143• ABOUT THE DHC PLANT• EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS• RESULTS AND CONCLUSIONOUTLINE ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20144• ABOUT THE DHC PLANT• EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS• RESULTS AND CONCLUSIONOUTLINE ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20145ABOUT THE DHC PLANTDHC plant in Nishi-Umeda district of Osaka, JapanThe 2nd  PlantThe 1st  PlantESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014Heat supply Schematic Diagram 6Total Supply Area ：approx.200,000㎡The plant supplies both chilled and hot water to commercial facilities, offices, theaters, and the train station, etc.AR1-5 X 5TR1,2 X 2TR3,4 X 2IST X 2The 2nd PlantStationRetail ShopDepartment StoreFit TheaterOfficeElectric RoomMachine Room (13F)1st PlantOptical Cable（Monitoring）BTR1,2 X 2ABOUT THE DHC PLANTCommercial 62%Office20%Station6%Theater4%Others8%Ration of Heat Supply AreaCommercial62%ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014Capacity of cold heat generators： 36,871 kW （10,500RT）Capacity of hot heat generators  ： 15,430 kWSymbol heat generator Capacity NumberAR1～5Gas-fired Absorption Water Chiller Boiler(= Absorption Chiller)Cooling Capacity : 3,516kW (1,000RT)5Heating Capacity : 2,900kWTR1,2 Centrifugal Chiller (Constant Speed ) Cooling Capacity : 3,516kW (1,000RT) 2TR3,4 Inverter Centrifugal Chiller Cooling Capacity : 1,758kW (500RT) 2BTR1,2 Centrifugal Chiller for Ice StorageCooling Capacity : 1,571kW (447RT)2Ice Making Capacity : 1297kW (369RT)IST1,2 Ice Storage TankCapacity of Thermal Storage :11,603kWh (3,300RTh) 2BO1,2 Hot Water Boiler Heating Capacity : 465kW 27ABOUT THE DHC PLANTESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20148OUTLINE• ABOUT THE DHC PLANT• EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS• RESULTS AND CONCLUSIONESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014■Commissioning Schedule■ Commissioning Team9AdviserPlant Owner , OperatorCommissioning AuthorityDesignerSupervisorBuilderMitsubishi Jisho Sekkei Inc., EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS2008 2009 2010 2011 2012 2013System DesignCunstructingCommissioningOperation ImprovementApril : CompletionMay : Grand OpeningESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 Verification of the designed performance of the systems and the equipment through the commissioning process Operational improvements in efficiency, based on the result of the commissioning10EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSPOLICY  ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 20141. Search for the most suitable operation methodin consideration of efficiency and running cost2. Commissioning and optimizing the number ofoperating inverter centrifugal chillers and thestart/stop timing3. Commissioning and optimizing the flow controlon the cooling water11EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSExamples of commissioning and operational improvementsESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 Regardless of cooling water temperature, theinverter centrifugal chiller is more efficient than other heat generators. As cooling water temperature decreases, the inverter centrifugal chiller increases its efficiency, compared to the absorption chiller.0.501.502.5040% 60% 80% 100%System COPCooling Water Temperature : 32℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption Chiller0.501.502.5040% 60% 80% 100%System COPCooling Water Temperature : 24℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption Chiller12EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSLoad Factor[％] Load Factor[％]Search for the most suitable operation method in consideration of efficiency and running costRelations of load factor/cooling water temperature and system COPESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 In terms of  running costs (heart unit price), the electric system (centrifugal chiller) is more advantageous than the gas system (absorption chiller)  In case of low load period in summer, the ice storage system is more advantageous than others in running costsRelations of load factor/cooling water temperature and running cost 0%20%40%60%80%100%120%140%160%180%200%40% 60% 80% 100%Heat Unit Price Ratio[%]cooling water temperature : 24℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption Chiller0%20%40%60%80%100%120%140%160%180%200%40% 60% 80% 100%Heat Unit Price Ratio[%]cooling water temperature : 32℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption Chiller◆Heat Unit Price Ratio ： 100% = Heat unit price of  centrifugal chiller with cooling water temperatureat 32℃ and  Load factor 100%)13EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSLoad Factor[％] Load Factor[％]Search for the most suitable operation method in consideration of efficiency and running costESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014Constant speed centrifugal chillerIce storage（Ice Melting Mode)Absorption chillerInverter centrifugal chiller14Operation order of the cold heat generatorsOperation order (from first to last)Inverter centrifugal chiller→Constant speed centrifugal chiller→Absorption chiller →Ice storageEXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSSearch for the most suitable operation method in consideration of efficiency and running costESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201415As the cooling water temperature decreases, the system COP improves by adding the second chiller earlier.EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSCommissioning and optimizing the number of operating inverter centrifugal chillersand the start/stop timing0.00.51.01.52.02.53.03.54.04.55.00 200 400 600 800 1000 120012℃16℃20℃24℃28℃32℃500RTTwo Chillers Operation(Solid Line)Cooling Water temperatureOne Chiller Operation(Dotted Line)Two chillers operation is more efficient from this point‣Cooling Outputs(RT)System COPEfficient operation by controlling number of operated  chillers (simulation)ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201416System COP improved with the 2nd inverter centrifugal chiller starting earlierEfficient operation by controlling number of operated  chillers(measured data)EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSCommissioning and optimizing the number of operating inverter centrifugal chillersand the start/stop timing0.00.51.01.52.02.53.03.54.04.55.00 200 400 600 800 1000 1200System COPCooling Outputs(Total of two chillers)[RT]Improvement of System COP500RTNov.2011 - Mar.2012  Normal OperationNov.2012 - Mar.2013  Earlier Start of Second ChillerESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201417Unit COP based on cooling water inlet/outlet temperatureThe unit COP data published from manufacturers are based on the inlet temperature and the constant flow systemIn case of the variable cooling water flow system, The unit COP is affected more by the outlet water temperature than by the inlet water temperatureChanges in the unit COP of the inverter centrifugal chiller0.01.02.03.04.05.06.07.00 20 40 60 80 100 120Unit COPLoad Factor[%]outlet 32℃outlet 36℃outlet 40℃outlet 20℃outlet 28℃★outlet 24℃Based on outlet temperature of cooling water16 - 24℃（Cooling Water Flow Rate : 50%）16～24℃（Cooling Water Flow Rate : 100%）16 - 24℃（Cooling Water Flow Rate : 100%）EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS0.01.02.03.04.05.06.07.00 20 40 60 80 100 120Unit COP ★inlet 24℃inlet 28℃inlet 32℃inlet 16℃inlet 12℃inlet 20℃Load Factor[%]Based on inlet temperature of cooling water16 - 24℃（Cooling Water Flow Rate : 50%）16 - 24℃（Cooling Water Flow Rate : 100%）Commissioning and optimizing the flow control on the cooling waterESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201418Energy simulationIn case of the variable cooling water flow system, the cooling water outlet temperature should be a parameter of controlComparison between the variable cooling water flow system and the constant system by simulation Based on the simulation, except for the mid summer (July and August), the constant cooling water flow system is more energy saving than the variable system in this plantEXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSCommissioning and optimizing the flow control on the cooling waterESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014Change in energy consumption by changing the water flow control （measured data）19The constant cooling water flow control has been appliedfor the inverter centrifugal chillers from the second year01,0002,0003,0004,0005,0006,0007,0008,0009,00010,00011,00012,00013,0002012/10/072012/10/28 2012/11/18 2012/12/09 2012/12/30 2/24｜3/2Consumed electricity per heat unit [kWh/GJ]Variable waterflow controlCooling tower funChilled water pumpCooling water pumpChillerConstant waterflow control2/10｜2/161/27｜2/21/13｜1/1912/30｜1/512/16｜12/2212/2｜12/811/ 8｜11/2411/4｜11/1010/21｜10/270/7｜10/13EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSCommissioning and optimizing the flow control on the cooling waterESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201420OUTLINE• ABOUT THE DHC PLANT• EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTS• RESULTS AND CONCLUSIONESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201421Annual average plant system COP of 1.35 has been achieved at the 3rd year after operation startPlant System COP= 𝑄𝐺𝑃+𝐸×𝑒𝑝Definition of the plant System COP Q：Total heat supply (chilled water and hot water)[KJ]Gp：Gas-fired Absorption Water Chiller Boiler [KJ]E：Total electricity consumption of the plant[kWh]ep：Conversion factor to primary energy[9,760kJ/kWh]RESULTS AND CONCLUSIONCOP1.35 is the top-class efficiency in JapanThis Plant1st year1.192nd  year1.293rd year1.35The Plant System COP of all the DHC plants in Japan of 20120 .00 .20 .40 .60 .81 .01 .21 .4システムＣＯＰ全電気D H Cコージェネ+D H Cごみ排熱利用電気ガス併用データ出典： 熱供給事業便覧平成2 4年版( )年月は供給開始を示すAverage value of all the plants COP 0.76Reference : Japan Heat Supply Business Association Hand book(2013)System COPDesign target of  this plant COP 1.2Achieved value at the 3rd year after operation start COP 1.351.4....0.400.2ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Op rations, Beijing, China, September 14-17, 201422(1) Top-class energy efficiency of DHC plants in Japan have been achieved by applying the commissioning process(2) In order to achieve assured energy savings, the commissioning process and operational improvements based on its results are very importantRESULTS AND CONCLUSIONCONCLUSIONESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201423EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSSearch for the most suitable operation method in consideration of efficiency and running cost0.501.502.5040% 60% 80% 100%System COPCooling Water Temperature : 32℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption ChillerLoad Factor[％]ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201424EXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSSearch for the most suitable operation method in consideration of efficiency and running cost0.501.502.5040% 60% 80% 100%System COPCooling Water Temperature : 24℃Inverter Centrifugal ChillerCentrifugal ChillerDirect Cooling Mode(Ice Storage System)Ice Melting Mode(Ice Storage System)Absorption ChillerLoad Factor[％]ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201425Ice storageEXAMPLES OF COMMISSIONING AND OPERATIONAL IMPROVEMENTSSearch for the most suitable operation method in consideration of efficiency and running costOperation order (from first to last)Absorption chillerConstant speed centrifugal chillerInverter centrifugal chillerConstant speed centrifugal chillerIce storage（Ice Melting Mode)Absorption chillerInverter centrifugal chillerESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 201426Definition of the Plant System COPQ ：Total heat supply (chilled water and hot water)[KJ]Gp：Gas-fired Absorption Water Chiller Boiler [KJ]E ：Total electricity consumption of the plant[kWh]Ep ：Conversion factor to primary energy[9,760kJ/kWh]Plant System COP= ESL-IC-14-09-25Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014

https://oaktrust.library.tamu.edu/bitstream/1969.1/152325/1/ESL-IC-14-09-25.pdf

Commissioning Process and Operational Improvement in the District Heating and Cooling-APCBC

Abstract

Similar works

Full text

Available Versions

Texas A&M University

Texas A&M Repository

Commissioning Process and Operational Improvement in the District Heating and Cooling-APCBC

Abstract

Similar works

Full text

Available Versions

Texas A&M University

Texas A&amp;M Repository

Texas A&M Repository