ice thermal storage systems - ashrae bi-state
TRANSCRIPT
![Page 1: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/1.jpg)
Ice Thermal Storage Systems
Greg Henderson
Director, Global Thermal Storage
![Page 2: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/2.jpg)
Agenda
• Ice storage basics
• Ice storage design considerations
– Full and partial storage systems
– Internal and external melt systems
• Ice storage installations and applications
![Page 3: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/3.jpg)
![Page 4: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/4.jpg)
Ice Build on Ice Coil Tube
![Page 5: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/5.jpg)
Ice Build on Ice Coil
![Page 6: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/6.jpg)
![Page 7: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/7.jpg)
What is Ice Storage?
• Ice Storage is the process of using a chiller or refrigeration plant to build ice during off-peak hours to serve part or all of the on-peak cooling requirement
![Page 8: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/8.jpg)
Ice Thermal Storage
How does it work?
![Page 9: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/9.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
Typical Cooling Load Profile
![Page 10: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/10.jpg)
Conventional System
Chiller
Cooling Load
![Page 11: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/11.jpg)
Ice Storage System
Ice Storage TankChiller
Cooling Load
![Page 12: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/12.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
Ice Storage Cycle
Ice Storage
Cycle
Ice Storage
Cycle
![Page 13: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/13.jpg)
Advantages of Thermal Energy Storage
• Reduced equipment costs
• Reduced energy and operating costs
• Increased flexibility to adapt to changing utility structures and requirements
• Reduces need for new power plants
![Page 14: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/14.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Po
wer
(Meg
aw
att
s)
Typical Daily Utility Load Curve
Demand Charges
High Time of Day Rates
Total Utility Capacity
![Page 15: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/15.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
Ice Storage Cycle
Ice Storage
Cycle
Ice Storage
Cycle
Demand Charges
High Time of Day Rates
![Page 16: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/16.jpg)
![Page 17: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/17.jpg)
![Page 18: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/18.jpg)
0
20
40
60
80
100
M 2 4 6 8 10 N 14 16 18 20 22
Time of Day
% G
en
era
tio
n
0
20
40
60
80
100
M 2 4 6 8 10 N 14 16 18 20 22
Time of Day
% G
en
era
tio
nElectric Generation Fuel Sources
Hydro-electric 0.2¢/kWh
Nuclear 0.4¢/kWh
Coal-fired steam 2.5¢/kWh
Combined cycle 3.0¢/kWh
Oil-fired steam 3.5¢/kWh
Diesel 6.5¢/kWh
Comb. turbine 7.0¢/kWhThe
StorageShift
![Page 19: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/19.jpg)
Thermal Storage System Environmental Advantages
• Require less kWh than conventional systems
• Utilize efficient power and produce fewer carbon dioxide emissions
• Energy line losses at night are 4% to 5% lower than during the daytime
Source: Source Energy and Environmental Impacts of Thermal Energy Storage, California Energy Commission - February 1996
![Page 20: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/20.jpg)
Advantages of Ice Thermal Storage
• Reduced equipment costs
• Reduced energy and operating costs
• Colder supply water temperature
![Page 21: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/21.jpg)
Advantages of Ice Thermal Storage
• Reduced equipment costs
– Only ~60% of chillers and heat rejection equipment required
– Requires only 1/4 to 1/6 of the space required for chilled water storage (~3Ft3/Ton-Hour)
– Requires less chiller plant plan area than instantaneous chiller system
![Page 22: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/22.jpg)
30,000 RT Output
16,000 RT Heat Rejection
![Page 23: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/23.jpg)
Advantages of Ice Thermal Storage
• Reduced equipment costs
• Reduced energy and operating costs
• Colder supply water temperature
![Page 24: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/24.jpg)
Ice Thermal StorageUses Less Energy
• During daytime, chillers operate at higher supply temperatures and greater efficiency when piped upstream of the ice storage
• At night, chillers operate when ambient temperatures are lower
• Pump and fan energy can be less when colder system supply temperatures are used
![Page 25: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/25.jpg)
EER of Air Cooled Chillers*
6
8
10
12
14
16
20 25 30 35 40 45 50 55
Leaving CHW
EE
R
95 Air 85 Air 75 Air
* includes heat rejection
75
85
95
“Normal” Design Point Pre-cooling
Ice-Making
![Page 26: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/26.jpg)
EER of Water Cooled Chillers*
10
12
14
16
18
20
20 25 30 35 40 45 50 55
Leaving CHW
EE
R
85 80 75
* excludes heat rejection
Pre-cooling“Normal”
Design Point
Ice-Making
75
80
85
![Page 27: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/27.jpg)
Ice Thermal Storage Reduces Operating Costs
• Reduces air conditioning kW demand by approximately 40%
• Reduces air conditioning kWh by up to approximately 15%
• Reduces electric utility costs
– Large percentage of energy usage is at night
– Daytime energy costs 2 to 5 times more than night time energy
![Page 30: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/30.jpg)
LEED Criteria
• Sustainable sites (14 possible points)
• Water efficiency (5 possible points)
• Materials and resources (13 possible points)
• Energy and atmosphere (17 possible points)
– Ozone depletion
– Optimize energy performance• Cost based analysis vs. ASHRAE 90.1
• Indoor air quality (15 possible points)
• Innovation & design process (5 possible points)
![Page 31: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/31.jpg)
Advantages of Ice Thermal Storage
• Reduced equipment costs
• Reduced energy and operating costs
• Colder supply water temperature
![Page 32: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/32.jpg)
Advantages of Cold Supply Water Temperature
• Smaller distribution pumps and piping
• Reduced pumping power
• Allows for economical building isolation (indirect interface) with smaller heat exchangers
• Provides better dehumidification and indoor air quality(IAQ)– 78°F (25.5°C) at 40% RH is more comfortable
than 76°F (24.4°C) at 50% RH
• Cold air distribution
![Page 33: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/33.jpg)
![Page 34: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/34.jpg)
Burj Dubai Tower
• Will become world’s tallest building at over 180 floors
• Currently at 156 floors
• 41,600 ton-hours
![Page 35: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/35.jpg)
Taipei 101
• Currently the world’s tallest building at 101 floors
• 36,400 ton-hours
![Page 36: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/36.jpg)
7th & 8th floors
37.8 F (3 C)
42nd floor
39.2 F (4 C)
74th floor
41.0 F (5 C)
Taipei 101
![Page 37: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/37.jpg)
Factors Favorable forIce Storage Systems
• Loads are of short duration
– Schools
• Loads occur infrequently
– Churches
– Sports venues
• Loads are cyclical in nature
– Process or batch cooling
![Page 38: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/38.jpg)
Factors Favorable forIce Storage Systems
• Loads are not well matched to availability of the energy source
• Energy costs are time-dependent
– Time-of-use energy rates
• Energy supply is limited
– Demand charges for peak energy use
• Utility rebates, tax credits, or other economic incentives are provided for the use of load-shifting equipment
![Page 39: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/39.jpg)
Potential Ice Storage Projects
• Commercial A/C and industrial
– Schools
– Hospitals
– Office buildings
– Internet data centers
– Hotels
– Airports
– Sports venues
– Manufacturing plants
![Page 40: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/40.jpg)
Potential Ice Storage Projects
• Commercial A/C and industrial
• District cooling
– Colleges and universities
– Corporate campuses
– Hospitals
– Convention centers
– Sports arenas
– Utilities
![Page 41: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/41.jpg)
Ice Thermal Storage Systems
Design Considerations
![Page 42: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/42.jpg)
Full Storage vs.
Partial Storage
![Page 43: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/43.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Batch Cooling or Process Load Profile
![Page 44: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/44.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Full Ice StorageBatch Cooling or Process Application
Ice Charge Ice Discharge
![Page 45: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/45.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Air Conditioning Load Profile
![Page 46: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/46.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Full Ice StorageAir Conditioning Application
Ice Charge Ice Discharge
![Page 47: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/47.jpg)
Ice Thermal Storage System DesignFull Ice Storage
Advantages
• Best suited for short, peak demand periods and/or high, peak loads
• Shifts largest electrical demand that provides the lowest operating cost
• Provides system standby capability and operating flexibility
Disadvantages
• Largest storage volume required
• Larger chiller required
• Most expensive thermal storage design
![Page 48: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/48.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Partial Ice StorageAir Conditioning Application
Ice Charge Chiller
Ice Discharge
![Page 49: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/49.jpg)
Partial Ice StorageAir Conditioning Application
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Ice Charge Chiller
Ice Discharge
![Page 50: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/50.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Partial Ice StorageAir Conditioning Application
Ice Charge Chiller
Ice Discharge
![Page 51: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/51.jpg)
0 2 4 6 8 10 12 14 16 18 20 22
Time of Day
Co
oli
ng
Lo
ad
(T
on
s)
Ice Charge Chiller
Ice Discharge
Base Chiller
![Page 52: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/52.jpg)
Ice Thermal Storage System DesignPartial Ice Storage
Advantages
• Best suited for long cooling periods
• Lower first cost due to reduced storage volume and smaller chiller
• Provides system operating flexibility
Disadvantages
• Less standby capability
• Less electrical demand shifted to off-peak
![Page 53: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/53.jpg)
Internal Melt vs.
External Melt
Indirect vs. Direct
Contact Cooling
![Page 54: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/54.jpg)
Ice Storage System Types
Direct Contact Cooling Indirect Contact Cooling
![Page 55: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/55.jpg)
Ice Thermal Storage Ice-on-Coil Technology
![Page 56: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/56.jpg)
Ice Thermal Storage System DesignIce on Coil - Internal Melt
• Cold glycol solution is circulated through the coil to the A/C system
• Warm glycol solution, circulating through the coil, is cooled indirectly by the melting ice
ICE
ICE ON COIL
WARM
GLYCOL
IN
COLD
GLYCOL
OUT
WARM
GLYCOL
MELTING OCCURS
FROM INSIDE
Indirect
![Page 57: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/57.jpg)
Ice Storage DesignInternal Melt (Indirect Contact)
![Page 58: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/58.jpg)
Ice Storage DesignInternal Melt Performance*
32
34
36
38
40
42
44
46
0 10 20 30 40 50 60 70 80 90 100
% Ice Meltout
Le
av
ing
Te
mp
era
ture
0
1
2
3
4
5
6
7
(°F) (°C)
*10 hour, constant load
w/o air agitation
![Page 59: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/59.jpg)
Ice Storage DesignInternal Melt (Indirect Contact)
Advantages
• Simple to design and operate– simple controls for various operating modes
– closed, pressurized loop
• Stable, cold discharge temperatures– 36°F to 38°F (2.2°C to 3.3°C) typical
• Durable steel construction– 150 to 300 psi (10.3 to 20.7 bar) design pressure
rating
– tested at 190 to 375 psi (13.1 to 25.8 bar)
• Flexible layout (modular tanks or vault design)
![Page 60: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/60.jpg)
Ice Storage TankChiller
Heat Exchanger
OptionalBase Chiller
Cooling Load
System Schematic
![Page 61: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/61.jpg)
Ice Storage DesignInternal Melt (Indirect Contact)
Disadvantages
• Heat exchanger required for chilled water in building loop
• Not able to discharge as quickly as direct contact cooling
– ice melt limited by flow through coil
![Page 62: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/62.jpg)
Ice Thermal Storage System DesignIce on Coil - External Melt
• Ice water is circulated through the ice storage tank to the A/C system
• Warm return water, circulating through the tank, is cooled via direct contact with the ice
Direct
ICE
ICE ON COIL
REFRIGERANT
OR GLYCOL
MELTING OCCURS
FROM OUTSIDE
WATERIN
WATEROUT
AIR
WARM
WATER
![Page 63: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/63.jpg)
Ice Storage DesignExternal Melt (Direct Contact)
![Page 64: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/64.jpg)
Ice Storage DesignExternal Melt Performance*
32
34
36
38
40
42
44
46
0 10 20 30 40 50 60 70 80 90 100
% Ice Meltout
Le
av
ing
Te
mp
era
ture
0
1
2
3
4
5
6
7
(°F) (°C)
*10 hour, constant load
![Page 65: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/65.jpg)
External Melt Supply Temperatures
0102030405060708090100
% Ice Remaining
32
33
34
35
36
37
38
39
40
Leavin
g W
ate
r T
em
p.
(°F)
Hours
1
2
4
12
6
![Page 66: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/66.jpg)
6000 Ton-HoursIce Storage
6000 Ton-HoursIce Storage
375 TRWater Chiller
375 TRWater Chiller
375 TRWater Chiller
(Spare)
34°FCWS
54°FCWR
42°FCWS
250 TRGlycol Chiller
250 TRGlycol Chiller
250 TRGlycol Chiller
(Spare)
21.4°FCGS
27.8°FCGR
2000 GPM
1500 GPM
External MeltSystem Schematic
![Page 67: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/67.jpg)
Ice Storage DesignExternal Melt (Direct Contact)
Advantages
• Lowest chilled water supply temperatures
• Quickest discharge capability
• Eliminates glycol from chilled water loop
![Page 68: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/68.jpg)
Ice Storage DesignExternal Melt (Direct Contact)
Disadvantages
• Chiller with lower temperature capability generally required
• Glycol control valves required on larger systems
• Heat exchanger may require to manage static head of open system
• More difficult to monitor amount of ice in inventory
![Page 69: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/69.jpg)
Ice Thermal Storage SystemsExternal Melt vs. Internal Melt
External Melt
• Project requires a constant, cold supply water temperature of 34°F (1°C) or quick discharge periods
• Trained operating staff available
• Large savings in distribution piping system
• Highest energy efficiency
Internal Melt
• Project does not require coldest possible supply temperature
• Simpler design and operation
• Individual buildings
• Energy efficiency is less critical (extra heat transfer step required)
![Page 70: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/70.jpg)
Ice Thermal Storage SystemsExternal Melt vs. Internal Melt
• Most air conditioning applications use internal melt
• Most process and district cooling systems use external melt
![Page 71: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/71.jpg)
![Page 72: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/72.jpg)
![Page 73: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/73.jpg)
Maryknoll Grade SchoolHonolulu, Hawaii
Below-Grade Concrete Tank
2,000 Ton-Hours Ice Storage
District Cooling Retrofit
![Page 74: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/74.jpg)
![Page 75: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/75.jpg)
![Page 76: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/76.jpg)
![Page 77: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/77.jpg)
![Page 78: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/78.jpg)
![Page 79: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/79.jpg)
![Page 80: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/80.jpg)
![Page 81: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/81.jpg)
![Page 82: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/82.jpg)
![Page 83: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/83.jpg)
Maryland Stadium AuthorityOriole Park at Camden YardsRavens Stadium at Camden
Yards Baltimore, Maryland
Buried Concrete Tank
13,000 Ton-Hours Ice Storage
![Page 84: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/84.jpg)
![Page 85: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/85.jpg)
![Page 86: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/86.jpg)
![Page 87: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/87.jpg)
![Page 88: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/88.jpg)
![Page 89: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/89.jpg)
![Page 90: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/90.jpg)
![Page 91: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/91.jpg)
![Page 92: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/92.jpg)
![Page 93: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/93.jpg)
![Page 94: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/94.jpg)
Comfort Link District CoolingBaltimore, Maryland USA
• 32,000 TR peak system capacity
• 21,650 TR chiller capacity
• 75,000 TH ice storage
• 10 miles+ of distribution system piping
• Chilled water distributed at 37°F (2.8°C)
• 50+ customers
– commercial and government office, hospital, data center, hotel, residential, convention center, entertainment and retail space
![Page 95: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/95.jpg)
Comfort Link Plant #2Saratoga and Eutaw Streets
Baltimore, Maryland
Above-Grade Steel Tanks
27,000 Ton-Hours Ice Storage
![Page 96: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/96.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 97: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/97.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 98: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/98.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 99: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/99.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 100: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/100.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 101: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/101.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 102: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/102.jpg)
Comfort Link Market Center Chilling Station – Construction (1999)
![Page 103: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/103.jpg)
Comfort Link Market Center Chilling Station – Completion (1999)
![Page 104: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/104.jpg)
![Page 105: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/105.jpg)
Comfort Link District CoolingBaltimore, Maryland USA
• Operations began in 1996 with traditional electric tariff– 10:00 AM to 8:00 PM peak window
– Fixed peak demand charge
– Time of day energy rates
• Began purchase of electricity through independent suppliers in June, 2002
• System flexibility allows daily changes to operating schedules to minimize spot market consumption and capacity charges
![Page 106: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/106.jpg)
Electric Cost Components - Typical UserSRC Current Market Estimate - PJM Mid-Atlantic
72%
5%
4%
19% Market - Energy Cost
Market - Capacity Cost
Market - Other Costs
Local Delivery / Utility
Current Market Supply Estimate, 1 Year:
$85-$88/MWh
![Page 107: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/107.jpg)
Electric Cost Components
• Energy– Based on prevailing market prices
– Daytime energy costs average twice nighttime energy costs
• Capacity– UCAP (generation capacity charge)
• Highest system load hour on each of 5 highest load days (not customer)
– Transmission
– More than $60/kW/year
![Page 108: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/108.jpg)
Energy Cost Operating Strategy
0
2000
4000
6000
8000
10000
12000
14000
16000
7/3/03
12:00 AM
7/3/03
6:00 AM
7/3/03
12:00 PM
7/3/03
6:00 PM
7/4/03
12:00 AM
7/4/03
6:00 AM
7/4/03
12:00 PM
7/4/03
6:00 PM
7/5/03
12:00 AM
7/5/03
6:00 AM
7/5/03
12:00 PM
Co
mfo
rt L
ink
kW
0
20
40
60
80
100
120
140
160
PJ
M IS
O P
ric
e (
$/m
W)
Chart courtesy of Comfort Link
![Page 109: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/109.jpg)
Energy Cost Operating Strategy
0
2000
4000
6000
8000
10000
12000
14000
16000
7/3/03
12:00 AM
7/3/03
6:00 AM
7/3/03
12:00 PM
7/3/03
6:00 PM
7/4/03
12:00 AM
7/4/03
6:00 AM
7/4/03
12:00 PM
7/4/03
6:00 PM
7/5/03
12:00 AM
7/5/03
6:00 AM
7/5/03
12:00 PM
Co
mfo
rt L
ink
kW
0
20
40
60
80
100
120
140
160
PJ
M IS
O P
ric
e (
$/m
W)
Chart courtesy of Comfort Link
![Page 110: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/110.jpg)
Energy Cost Operating Strategy
0
2000
4000
6000
8000
10000
12000
14000
16000
7/3/03
12:00 AM
7/3/03
6:00 AM
7/3/03
12:00 PM
7/3/03
6:00 PM
7/4/03
12:00 AM
7/4/03
6:00 AM
7/4/03
12:00 PM
7/4/03
6:00 PM
7/5/03
12:00 AM
7/5/03
6:00 AM
7/5/03
12:00 PM
Co
mfo
rt L
ink
kW
0
20
40
60
80
100
120
140
160
PJ
M IS
O P
ric
e (
$/m
W)
Chart courtesy of Comfort Link
![Page 111: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/111.jpg)
Demand Limiting Operating Strategy
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour
To
tal
Syste
m T
on
s (
000)
Chiller Ice
Chart courtesy of Comfort Link
June 27, 2007
High of 100°F (37.8°C)
Low of 80°F (26.7°C)
12 mW
Demand Shift
![Page 112: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/112.jpg)
Record Heat and Record Loads
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour
To
tal
Syste
m T
on
s (
000)
Chiller
Chart courtesy of Comfort Link
August 8, 2007
High of 108°F (42.2°C)
Low of 86°F (30.0°C)
(1) 1750 TR chiller out of service
Load Leveling Operating Strategy
![Page 113: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/113.jpg)
Load Leveling Operating Strategy
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour
To
tal
Syste
m T
on
s (
000)
Chiller Ice
Chart courtesy of Comfort Link
August 8, 2007
High of 108°F (42.2°C)
Low of 86°F (30.0°C)
(1) 1750 TR chiller out of service
6 mW
Demand Shift
![Page 114: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/114.jpg)
Demand Limiting Operating Strategy
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour
To
tal
Syste
m T
on
s (
000)
Chiller Ice
Chart courtesy of Comfort Link
August 8, 2007
High of 108°F (42.2°C)
Low of 86°F (30.0°C)
11 mW
Demand Shift
Predicted performance with all chillers in service
![Page 115: Ice Thermal Storage Systems - Ashrae Bi-State](https://reader030.vdocuments.us/reader030/viewer/2022012023/6169d4e411a7b741a34bdafd/html5/thumbnails/115.jpg)
Ice Thermal Storage Systems
Greg Henderson
Director, Global Thermal Storage