optimal centrifugal chiller system for the middle east ... · 2.3 gcc region 3. climate condition...
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15th Dec 2016
Optimal centrifugal chiller system for the middle east region considering the climate and the cooling load.
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1. Introduction
1.1 Trend of District Cooling Plant in GCC Region
1.2 Issue for DHC Plant in GCC Region
2. Experiences of District Heating and Cooling
2.1 Tokyo
2.2 South East Asia
2.3 GCC Region
3. Climate Condition and Characteristic of Cooling Load
3.1 Dry-bulb temp 3.2 Wet-bulb temp 3.3 Cooling water temp
3.4 Cooling Load
4. Basic design for DC plant in GCC
4.1 Chiller design for DC plant in GCC
4.2 Plant Specification
4.3 Optimal Control System
4.4 Annual Energy Consumption Results and Consideration
5. Conclusion
Contents
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1. Introduction
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1.1 Trend of District Cooling Plant in GCC Region
1. High DC plant demand in GCC1
Total capacity of DC plants in UAE, KSA and Qatar is 29% of the world in 2014.
2. Further growth of DC plant marketLarge capacity DC plants have been
constructed and under development in
GCC region. The DC plants in the region
will be 30 million RT until 20302.
3. Large capacity of DC plant.Scale of new DC plants is much larger than
conventional plants, like Madinah Hajj City
and Makkah.
1)UAE, Bahrain, Kuwait, Oman, Qatar, KSA.
The value includes the value of UAE, KSA, Qatar and Iran.
2) 4th Annual District Cooling Saudi Arabia Summit , Sep 2013.Fig1.Estimated cooling capacity of DC plant in GCC region
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1.2 Issue for DC Plant in GCC Region
Design & method of operation for DC plant should be optimized to suit the climate
and the characteristic of cooling load in each region. The technologies would
reduce both capital and operating expenditure of the DC plants.
1. Optimal method for operating expenditureA operation method should be based on actual site condition in each region. Following
method would reduce the expenditure for DC plants.
1.1 Chiller number control: Operate chiller in efficient and high performance range
1.2 Control flow rate of chilled water variably
1.3 Control flow rate of cooling water variably
2. Optimal design for capital expenditureFollowing design for chiller and DC plant would reduce the expenditure.
2.1 Use large capacity chiller with 3,000 RT or more
2.2 Reduce footprint for large capacity chiller without cooling capacity
2.3 Reduce total chiller number installed in each DC plant
We have considered DC plant design and operation by using these methods in
Japan, Singapore and GCC region.
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2. Experiences
of District Heating and Cooling
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2.1 Tokyo
1. Climate and operation
(1)Humid summer, cold winter
(2)Chilled water supply throughout the year, and
steam supply in winter for offices, hotels and so on
(3)Ice storage at night because of high electrical bills
($0.15 – 0.16/kWh)2
2. Commercial Operation: since April, 2003
3. Supply Capability
Chilled Water: 16,800 RT Steam: 71.3 t/h
4. Main Units
(1)Chilled Water Supply
Absorption Chiller: 2,500 RT×4, 850RT×2
Centrifugal Chiller: 900 RT×3
Ice Storage Bath : 5,700 RTH×3
(2) Steam Supply
Steam boiler: 15 t/h×3, 9.6 t/h×1
Exhaust heat boiler: 8.35 t/h×2
DHC Plant in Tokyo, Shinagawa Station-East Area1
1) http://www.jdhc.or.jp/article/%E5%93%81%E5%B7%9D%E9
%A7%85%E6%9D%B1%E5%8F%A3/
2) http://www.tepco.co.jp/ep/corporate/plan_h/plan06.html
Fig3.Appearance of Shinagawa Station-East Area
Our headquarters!
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2.2 South East Asia
Marina Bay Sands, in Singapore
1. Climate and operation
(1)Humid summer throughout the year
(2)Chilled water supply for offices, hotels
and so on.
(3)Ice storage at night because
of High electrical bills ($0.08 – 0.13/kWh)2
2. Commercial Operation
since July, 2005
3. Supply Capability: 43,531 RT
4. Main Units
Centrifugal chiller: 3,697 RT×2 (ice storage)
2,844 RT×11(5, ice storage)
2,000 RT×2
853 RT×1
Fig4. Appearance of Marina Bay Sands1
1) http://www.mhi.co.jp/discover/graph/inquiry/no169.html
2) http://www.nna.jp/articles/show/20160401spd011A
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2.3 GCC Region
Madinah Hajj City Project, in KSA
In this presentation, we have considered the optimal design and operation for the
three places (Tokyo, Singapore and Madinah Hajj), Makkah in KSA, Lusail in Qatar and
Dubai on the basis of the following conditions
(1) Target area: Tokyo, Singapore, Madinah Hajj, Makkah, Lusail, Dubai
(2) Climate condition: Outside air temperature of 3 hours on behalf every month
(3) Cooling capacity of DC plant: 30,000 RT
(4) Chiller select: 5,000 RT, PL unit.
Fig5. Appearance of Madinah Hajj City Project1
1. Climate and operation
(1)Hot summer and relative warm climate
throughout the year
(2)Chilled water supply for offices, hotels and so on.
Electrical bills ($0.04 – 0.08/kWh)2
2. Commercial Operation: since 2018
3. Supply Capability: 200,000 RT
4.Main Units
Centrifugal Chiller: 2,500 RT,VSD×80
1) https://www.thebig5hub.com/news/2016/january/in-pictures-top-10-projects-in-makkah-and-madinah/ 2)http://www.nna.jp/articles/show/20160401spd011A
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3. Climate Condition
and Characteristic of Cooling Load
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3.1 Dry-Bulb Temperature
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
Makkah
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Out
side
air t
empe
ratu
re(℃
)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
Tokyo
Singapore
Madinah
Lusail Dubai
※Weather data source : World Weather Online Using the Outside air temperature of 3 hours on behalf every month. Number of statistics: 8 per month×12=96
Although GCC countries are the highest temperature level that we have never
experienced in Japan . But the experience of Singapore must be useful, and the
temperature difference throughout the year in Tokyo is able to take advantage for the
design and method of operation
Fig.6 Dry - Bulb Temperature
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3.2 Wet-Bulb Temperature
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
※Weather data source : World Weather Online Using the Wet-bulb temperature of 3 hours on behalf every month. Number of statistics: 8 per month×12=96
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Wet
bul
b te
mp(
℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
Makkah
Tokyo
Singapore Madinah
Lusail Dubai
Fig.7 Wet-Bulb Temperature
Wet-bulb temperature of GCC countries is less than that of Singapore.
the fluctuation range is small enough.
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3.3 Cooling Water Temperature
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
※Weather data source : World Weather Online Using the Cooling water inlet temperature of 3 hours on behalf every month. Number of statistics: 8 per month×12=96
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Coo
ling
wat
er in
let
tem
pera
ture
(℃)
Time(h)
JAN. FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
Makkah
Tokyo Singapore Madinah
Lusail Dubai
Fig.8 Cooling Water Temperature
Cooling water temperature changes widely in Japan through a year.
In Singapore it is almost constant.
In Madinah, Makkah, Lusail and Dubai it is narrow.
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3.4 Cooling Load
※Using the Cooling load of 3 hours on behalf every month. Peak load:30,000USRt
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
0
5000
10000
15000
20000
25000
30000
35000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Cap
acity(
USR
t)
Time(h)
JAN FEB MAR APR MAY JUNJUL AUG SEP OCT NOV DEC
Makkah
Tokyo Singapore Madinah
Lusail Dubai
Fig.9 Cooling Load (24h×12month)
In Japan, Load fluctuation is a large at daytime and small at night time.
In Singapore, Medina, Mecca, Lusail and Dubai, these load characteristics
are similar
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4. Basic design for DC plant in GCC
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4.1 Chiller design for DC plant in GCC
1.We suggest 3 concepts of chiller design for DC plant in GCC to reduce capital expenditure.
(1). Large capacity, more than 3,000 RT
(2). Small footprint with the large capacity chiller
(3). High performance chiller even under the GCC condition
2.We suggest 3 solutions in order to meet the above concepts.
(1). Big capacity compressor apply for the chiller
(2). Dabble compressors on one chiller, Parallel unit.
(3). Series-Counter flow configuration by one Parallel unit or two units.
Larger capacity chillers and the smaller footprint should be selected to be less the plant
building cost.
3. Optimal control system
The optimal operation system controls the number of chiller, chilled water flow and cooling
water flow to reduce the operation expenditure in accordance with the cooling water
temperature and the cooling load. Reduction of the operation cost will be huge by using the
optimal operation.
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4.2 Plant specification
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FSD VSD
30,000 30,000
5,000 5,0006 6
3,498 3,4985.0 5.0
13/4.4 13/4.4
1,655 1,655
53.4 53.413.0 13.090 90
35/43.5 35/43.5
2,107.8 2,107.8
31.0 31.020.0 20.0200 200
DC plant capacity(USRt)
Capacity(USRt)
Cooling water pump power(kW)
Model No.
Unit nuber
Power Input(kW)
Pump head(mAq)
Rated COP
Evaporator pressure drop(kPa)
Chilled water pump power(kW)
Condenser pressure drop(kPa)
Chilled water(℃)
Cold water flow rate(m3/h)
Cooling water(℃)
Cooling water flow rate(m3/h)
Pump head(mAq)
※1 FSD:Fixed Speed Drive chiller, VSD:Variable Speed Drive chiller
※2 Chilled water pump head=Head loss of straight pipe+Piping fittings,
valves and others+Strainer(3mAq)+Control valve(3mAq)+Head loss and flow rate of Evaporator
※3 Cooling water pump head=Head loss of straight pipe+Piping fittings,
valves and others+Strainer(3mAq)+Control valve(3mAq)+Open-type cooling tower(10mAq)+Head loss and flow rate of Condenser
※1 ※1
※2 ※2
※3 ※3
Following table shows specifications of chillers with FSD and VSD
4.2.1 Chiller Specifications for 30kRT Plant
Table.1 Specifications of chiller
Low pressure drop
Low pressure drop
Large capacity
Large temperature
difference
High performance
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4.2.2 Part Load Performances
0
2
4
6
8
10
12
14
16
18
0 20 40 60 80 100 120
CO
P(-
)
Cooling Capacity(%)
Estimated Part Load Performance Curve
35℃
31℃
27℃23℃
19℃
15℃
12℃
0
2
4
6
8
10
12
14
16
18
0 20 40 60 80 100 120
CO
P(-
)
Cooling Capacity ( % )
Estimated Part Load Performance Curve
19℃
15℃
31℃
12℃
35℃
27℃
23℃
High performance characteristic in actual operation range
Fig.10 Part load performance curve
FSD VSD
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4.2.3 Optimal control for PL type
35 4.72 4.90 5.03 5.14 5.20 5.23 5.23 5.20 5.14 5.08 4.9934 4.81 4.99 5.13 5.24 5.31 5.34 5.33 5.31 5.25 5.18 5.1032 5.15 5.23 5.34 5.46 5.53 5.56 5.56 5.54 5.49 5.42 5.3330 5.56 5.63 5.67 5.69 5.76 5.80 5.81 5.78 5.74 5.67 5.5828 6.02 6.09 6.12 6.13 6.12 6.10 6.07 6.05 6.00 5.93 5.8726 6.57 6.62 6.64 6.63 6.61 6.58 6.54 6.49 6.43 6.36 6.2824 7.20 7.24 7.24 7.23 7.19 7.15 7.09 7.02 6.94 6.85 6.7522 7.96 7.98 7.96 7.93 7.87 7.81 7.73 7.63 7.53 7.42 7.2920 8.88 8.87 8.83 8.77 8.69 8.59 8.48 8.36 8.22 8.07 7.9118 10.01 9.97 9.89 9.80 9.68 9.54 9.39 9.22 9.04 8.84 8.6316 11.45 11.36 11.23 11.07 10.90 10.70 10.48 10.25 10.00 9.73 9.45
50 55 60 65 70 75 80 85 90 95 100
Coolin
g w
ate
r in
let te
mp
.(℃
)
Higher COP value is shown at each condition, cooling load and cooling water
temperature in Fig.11, comparing with performance between FSD and VSD.
VSD is better performance in low cooling water temperature.
FSD is better performance in high cooling water temperature and high
cooling load
※1 FSD:Fixed Speed Drive chiller, VSD:Variable Speed Drive chiller
Fig.11 COP Comparison between VSD and FSD
Tokyo
Singapore
Madinah Dubai, Makkah, Lusail
FSD / VSD
Cooling load.(%)
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4.2.4 Comparison of the Unit Layout
Footprint of 2 single units is about the same of a parallel unit in the case of our chillers.
Fig.13 Installation Area 117m2
10.3m
11.5
m
19.5m
5.0
m
Fig.12 Installation Area 118m2
Series counter flow by 2 single units
5000RT
Series counter flow by a parallel unit
5000RT
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4.2.5 Plant Layout
30.4m
19.3
m
Chiller water inlet Chiller water outlet
Cooling water outlet Cooling water inlet
5,000RT
The layout shows the minimum area for 30kRT plant
with 6 parallel centrifugal chillers.
Tube
cleaning area
Fig.14 Plant Layout
Tube
cleaning area
Tube
cleaning area
Fig.15 Outline of 5kRT chiller
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4.3 Optimal control system
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・・・・・
4.3.1 Outline of control items
The optimal control system is able to control six items of following (1) –(6) in Fig.16
show the system diagram.
The In this presentation, COP and system COP were calculated in consideration of
(1) Multiple chiller control, (2) Chilled water variable flow control and (3) Cooling water variable
flow control.
Cooling Tower
Cooling Water Pump
Chiller
Chilled Water Pump
Cooling Water Inlet
Cooling Water Outlet
Chilled Water Outlet
Chilled Water Inlet
(1) Multiple chiller control
(2) Chilled water
variable flow control
Water supply Header
(3) Cooling water
variable flow control
(5) Cooling water
bypass valve control
(6) Chilled water bypass valve control
(4) Cooling tower
operation control
The parallel
series counter flow
chillers, chilled
water pumps and
cooling water
pumps are installed
on same floor.
Cooling towers
are on the top
Fig.16 Diagram of the DC plant
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4.3.2 Multiple Chiller Control
Optimal load area
FSD VSD Inlet temp of cooling water
Optimal load area
Fig.17 Optimal load range of FSD and VSD
(1) An Optimal load range is unique to each cooling water temperature in case of VSD, and to each chiller. The range is able to be calculated and transmitted to the control system via the operating box of the chiller. An Optimal range is around maximum load for FSD.
冷却水流量
Co
olin
g W
ate
r F
low
ra
te
Rated
Min
Chiller Operation Load
a
■Cooling Tower
■Cooling Water Pump
■ChillerEnerg
y c
onsum
ption
Value of Cooling Water Flow (%)
b
Optimal flow rate for
cooling water pump
Fig.18 Cooling water variable flow control
(2)Adequate chilled water flow minimizes (6) bypass flow between the inlet and outlet header.(3)An Optimal flow range of cooling water is decided by the cooling load in Fig.18-a, and ,minimize the
energy consumption (Fig.18-b)
Inlet temp of cooling
water
Cooling Load (%) Cooling Load (%)
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4.4 Annual energy consumption
and consideration
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4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
0 20 40 60 80 100 120
Cooling load (%)
FSD VSD
2
4
6
8
10
12
14
0 20 40 60 80 100 120Cooling load (%)
FSD VSD
130.3133.8 132.2
137.5
4.3
4.62.7
2.69.5
10.3
7.1
7.0
120
125
130
135
140
145
150
155
FSD VSD FSD VSDConventional Control Optimal Control
44.9 40.646.6 43.4
2.12.4
0.90.8
4.65.3
2.22.1
0
10
20
30
40
50
60
FSD VSD FSD VSDConventional Control Optimal Control
4.4.1 Tokyo and Singapore
Cooling Water PumpChilled Water PumpChiller
Fig19-(a)Annual energy consumption in Tokyo
VSD:7.91FSD:6.08
Fig19-(b) COPsys through the year in Tokyo
The VSD is better than the FSD by more than 6% in Tokyo at the view of Annual energy consumption. The Optimal control system has a reliable advantage in spite of the drive unit. Both VSD and Optimal control system are useful in the region has fluctuation of cooling water temp and cooling load.
(GW
h/Y
ear) 51.6 48.3 49.7 46.3
5.84
System
COP
6.07 6.516.25
The VSD is worse than the FSD by about 3% due to electrical loss. High performance FSD chillers should be applied for Singapore site.
Fig20-(a)Annual energy consumption in Singapore Fig20-(b) COPsys through the year in Singapore
(GW
h/Y
ear)
Cooling Water PumpChilled Water PumpChiller
5.04 5.11 4.944.89
144 149 142 147
System
COP
Tokyo
Singapore
Tokyo Tokyo
Singapore Singapore
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88.478.1
91.5 83.9
4.34.7
2.42.2
9.510.4
4.84.7
0
20
40
60
80
100
120
FSD VSD FSD VSDConventional Control Optimal Control
97.1 96.4 99.395.9 94.3
99.294.6 93.8 96.793.3 91.6
96.6
0
20
40
60
80
100
120
FSD(Conventional Control) VSD(Conventional Control)FSD(Optimal Control) VSD(Optimal Control)
Makkah Lusail Dubai
GWh/Year
4.4.2 GCC region
Fig22-(a) Annual energy consumptions of GCC region
Makkah Lusail Dubai
Fig22-(b) COPsys through the year in GCC region
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
0 20 40 60 80 100 120
Cooling load (%)
FSD VSD
Dubai
5.43 5.50 5.58 5.65 5.47 5.60 5.62 5.76 5.31 5.32 5.45 5.46
Cooling Water PumpChilled Water PumpChiller
(GW
h/Y
ear)
102 93.2 98.7 90.8
6.84 7.08 7.687.50
6.0
7.0
8.0
9.0
10.0
11.0
0 20 40 60 80 100 120
Cooling load (%)
FSD VSD
Madinah
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
0 20 40 60 80 100 120
Cooling load (%)
FSD VSD
Lusail
Fig20 Annual energy consumption in
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
0 20 40 60 80 100 120
Cooling load (%)
FSD VSD
Makkah
High performance FSD chiller, are suitable for typical GCC region, Makkah Dubai and Lusail. The Series counter flow parallel unit is one of best ways for DC plant in GCC region.
Madinah
In Madinah, the VSD is better than the FSD by about 9% at the view of annual energy consumption due to low cooling water temperature. The Optimal control system reduces additionally about 3% energy consumption.
The combination FSD & Optimal control system is better suited to typical GCC region, Makkah Dubai and Lusail, due to high cooling water temperature.
System
COP
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5. Conclusion
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5. Conclusion
1. High performance FSD centrifugal chiller is suited to DC plant
in GCC region, due to high temperature cooling water.
2. The Optimal control system is reduce the energy consumption
of the DC plant by approx. 3% in any case.
3. If temperature difference through a year is large, the
combination VSD chillers and Optimal control system is best.
It improves the performance of the DC plant by 10%
4. The series counter flow parallel unit with double
compressors is ideally suited to DC plant in GCC region, due
to large capacity, high performance and small footprint.
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