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DISTRICT COOLING HEAT REJECTION Dubai 09/04/2018
DISTRICT COOLINGHEAT REJECTION
Dubai09/04/2018
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples
Air Cooled VS Water Cooled in DUBAI
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples
Air Cooled VS Water Cooled in DUBAI
Centralized production and distribution of Cooling Energy
District cooling is an integral energy infrastructure to reduce strain on the electric grid caused by
increasing demands for air conditioning, which typically create 50%-70% of peak electricity demand
DISTRICT COOLING
Industrial-grade equipments and industrial practices ensure the reliability and
safety
Adding a thermal energy storage can reduces the costs and the environmental
impact (green technology)
Reduction in CO2 Emissions
Operation and Maintenance Services
provided by experts
Possibility of Energy
Storage
Higher Reliability & Efficiency
Recognized Green Technology with Carbon Credit
Optimization of the installed
cooling capacity
Reduction in peak Electricity Demand
Mitigate HeatIsland Effect
BENEFITS OF DISTRICT COOLING
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples
Air Cooled VS Water Cooled in DUBAI
Heat Rejection Technologies
Modular High-Efficient Industrial Chillers
Thermal Energy Storage Tank
DISTRICT COOLING HEAT REJECTION
Electrical & Control Modules
Higher Electrical Consumption
Better efficiency at night with low peak tariff
No water consumption
No Cooling Water pumps
Low and economical operation and maintenance
Clean system with no potential risk of contamination
COOLING TOWER EVAPORATIVE
DRY CONDENSATION
SEA WATER
Low electrical consumption
High water consumption
(can work with TSE)
Cooling Water required
Periodical chemical treatment required
Potential risk of Legionella Contamination
Low Electrical Consumption
No water consumption (water is passed through)
Special materials are needed (Titanium)
The river or the sea water must be close to the power plant
DISTRICT COOLING HEAT REJECTION
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples
Air Cooled VS Water Cooled in DUBAI
Electrical Consumption KW/TRWater Cons
l/TRh
Technology Chiller CW Pumps Fans CHW Pumps Total for TSE water
Cooling Tower + Water Cooled Chiller 0.65 0.04 0.04 0.12 0.85 12.00
Air Cooled Industrial Direct Condensation 0.96 0 0.13 0.12 1.21 0
Sea Water Cooled Chillers Ti Condensers 0.63 0.05 0 0.12 0.8 0
WORST DESIGN CONDITIONS (WB: 31 ºC, DB:47 ºC, SW TEMP: 33 ºC)
COMPARISON OF TECHNOLOGIES
DISTRICT COOLING HEAT REJECTION
DISTRICT COOLING HEAT REJECTION
DISTRICT COOLING HEAT REJECTION
Electrical Consumption KW/TRWater Cons
l/TRh
Technology Chiller CW Pumps Fans CHW Pumps Total for TSE water
Cooling Tower + Water Cooled Chiller 0.59 0.04 0.03 0.12 0.78 12.00
Air Cooled Industrial Direct Condensation 0.74 0 0.13 0.12 0.99 0
Sea Water Cooled Chillers Ti Condensers 0.52 0.05 0 0.12 0.69 0
YEARLY AVERAGE
COMPARISON OF TECHNOLOGIES
DISTRICT COOLING HEAT REJECTION
THERMAL ENERGY STORAGE
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples And Recommendations
Air Cooled VS Water Cooled in DUBAI
Chillers selection and arrangement
1. Select double compressor chillers or arrange the chillers in series counter flow
2. Select the chiller with electronic expansion valves able to work at 100% load and reduced Cooling Water Temperature
3. Select the chillers at ZERO Tolerance
KEY DESIGN GUIDELINESS
COOLING TOWERS - EVAPORATIVE
Heat rejection
1. Evaluate the use of evaporative condensers
2. Select the optimum Cooling water flow to obtain the maximum overall efficiency considering chiller efficiency and pumping cost
3. Select cooling tower material according to the site conditions (FRP)
4. Try to use TSE Water
Use of High-Capacity Industrial Condensers
1. Ensure fin spacing of at least 2.8mm
2. Ensure anti corrosive coating (kathodische Tauchlackierung KTL)
3. Chose large size fans (same concept as for cooling towers)
Use High-Efficiency Compressors
1. Twin Screws oil flooded (medium and large capacities)
2. Centrifugal with magnetic bearing and inverter (medium capacities)
3. Four Stage centrifugal (large and very large capacities)
AIR COOLED
KEY DESIGN GUIDELINESS
PLANT INTEGRATION IN THE SURROUNDING AREAS
Building DC Plant Implementation
ABDALI DISTRICT HEATING AND COOLING PLANT
Materials in contact with sea water
1. Select Full titanium Condensers
2. Select Super Duplex Pumps
3. Select non metallic piping (GRP or HDPE)
Environmental
1. Use environmental friendly fouling protection
2. Respect the temperature limits for discharge (typically 5ºC increase)
Filtration
1. Ensure adequate filtration
2. Use back flushing
SEA WATER COOLED
KEY DESIGN GUIDELINESS
AYLA OASIS DISTRICT COOLING PLANT
AGENDA
District Cooling
DC Heat Rejection
Design Efficiency VS Average Efficiency
Practical Examples And Recommendations
Air Cooled VS Water Cooled in DUBAI
CHARACTERISTICS TRADITIONAL SOLUTION AIR COOLED SOLUTION
Rated Efficiency 0.85 kW/TR 1.21 kW/TR
Yearly Efficiency 0.78 KW/TR 0.99 kW/TR
Heat Rejection DeviceCooling Towers
Indirect condensationAerocondensers
Direct Condensation
Refrigerant R134a as standard R134a as standard
Water ConsumptionPotable: 8 l/TRhTSE: 12 l/TRh
ZERO
Special requirementsSand separators, chemical injection, CT fill
replacementN/A
Running cost (Elect + Water+ Chemicals)1 Potable: 0.441 AED/TRhTSE: 0.372 AED/TRh
0.426 AED/TRh
ADVANTAGES Standard solution
• No water consumption• Low maintenance cost• Low operation cost• No water supply dependant.• No legionella risk
Note 1:
Electricity cost considered: 0.43 AED/kWh.
Potable water cost considered: 11.5 AED/m3
TSE cost considered: 1.32 AED/m3
