What is District Cooling?
District Cooling concept is similar to conventional Air Conditioning system except that the chilled water is produced in a central location at high efficiency and delivered to the buildings connected to the system by a piping network. This innovative service eliminates the need for the building owners to own, operate and maintain major chilling equipment. With District Cooling system, customers simply subscribe to contractual amount of load tons. District Cooling plants are far more efficient than conventional systems using half the energy consumed by existing conventional air-cooled systems.
District Cooling Benefits
District Cooling system delivers a variety of benefits to customers including financial, comfort convenience, flexibility and reliability.
Comfort and Convenience
District Cooling system provides better temperature control and quieter building with no heavy equipment generating vibration and noise making employees efficient and more productive. From building manager’s standpoint, it is attractive to provide reliable comfort without worrying about managing large equipment, labor and materials.
For the customers, District Cooling is a reliable source of cooling because the need to acquire install and maintain large cooling equipment is eliminated. District Cooling is more reliable than conventional AC because it uses industrial equipment and provides system redundancy with extensive and expert maintenance.
Low energy consumption is not only a financial victory, it also helps to respect and preserve environment by reducing Green House Gases emissions, controlling of phase-out CFC & eventually HCFC.
Potential Capital & Operating Savings Associated with District Cooling
By choosing District Cooling service, a building avoids a large capital and Operating costs including:
- Elimination of major chilling equipment + pumps + controls & BMS, all associated ancillaries, electrical works and installation.
- Construction cost of space to house the equipment (Civil work)
- Transformers, electrical equipment and cables
- Engineering and services
- Replacement capital cost
- Reduced electricity bill
- Less maintenance & spare parts cost
- Reduced operating personnel
- Reduced property and liability insurance cost with elimination of major equipment associated with the risk of fire
- Reduced breakdown and unscheduled repairs
- Visual and acoustic issues
- Reliable source of cooling with chilled water is always available in the pipeline day and night thus avoiding the need to start and stop cooling units
- Readily available capacity for future expansion
- Useable space is increased where large equipment and ancillaries are removed
- Reducing demand on the national power grid
- Enhancing business opportunity
Chilled water supply through retifculation piping network to offtakers
Chiller plant with thermal energy storage tank
With the new time-of-use electrical rates, District Cooling system becomes far more economical source of cooling energy as compared to in-building chillers system. The savings are realized from the following facts.
- Eliminate the need of acquiring major mechanical, controls and electrical equipment
- Eliminate the need of maintaining, replacing and operating major equipment
- Shifting electric use to low cost off-peak periods using inexpensive power at night
- District Cooling system is far more efficient than air-cooled system
With District Cooling system, chilled water is produced in a more environmental friendly manner whereas:
- 50%jreduction in power consumption means considerable reduction in power generation and consequently the production of CO2 major cause of Global Warming
- The chiller operates on R134a refrigerant eliminating the use of refrigerants having non-zero ozone depletion potential
- The plant will comply with Montreal Protocol on the phase-out of ozone-damaging CFC
A comparative analysis has been conducted for a typical 500 TR system based on a typical ME operating load profile. The analysis included the following incentivce
Cooling Load Operating Profile
The above analysis showed significant savings associated with subscribing to District Cooling system. Thanks to SEC new T.O.U electricity tariff
Will the chilled water on the District Cooling side and the building side mix?
No. Plate & Frame heat-exchangers are installed at each customer buildings to provide the interface
between District Cooling system and the building cooling system. This done in order to:
- Isolate the plant equip and distribution piping from contamination that may exist in customer building
- Minimize the impact on the mechanical system & isolate the plant equip from high static Pressure that may be caused by the elevation of the customer building
Who are the potential District Cooling candidates ?
- Large buildings having variable flow pumping in close vicinity of the District Cooling plant
- Expanding facility and/or retirement of aging or inefficient chillers
- New buildings under design/construction stage
- Established buildings addressing energy and CFC Phase-out due to environmental concerns
Will tying buildings into District Cooling plant cause any interruption of space cooling?
No, Tying off-takers buildings into the chilled water piping loop will cause no interruption of space cooling of the existing facilities. In most cases, it happens during nighttime or shutdown periods
Where do we site the Plant?
In Hadeed, Jubail Industrial City and it’s successfully operating since year 2011 with a 30,000 tones capacity inside the District Cooling Plant – Hadeed Steel Plant premises.