Chillers

• Increase the chilled water temperature set point if possible.
• Use the lowest temperature condenser water available that the chiller can handle.
(Reducing condensing temperature by 5.50C, results in a 20 - 25% decrease in compressor power consumption)
• Increase the evaporator temperature
(5.50C increase in evaporator temperature reduces compressor power consumption by 20 - 25%)
• Clean heat exchangers when fouled.
(1 mm scale build-up on condenser tubes can increase energy consumption by 40%)
• Optimize condenser water flow rate and refrigerated water flow rate.
• Replace old chillers or compressors with new higher-efficiency models.
• Use water-cooled rather than air-cooled chiller condensers.
• Use energy-efficient motors for continuous or near-continuous operation.
• Specify appropriate fouling factors for condensers.
• Do not overcharge oil.
• Install a control system to coordinate multiple chillers.
• Study part-load characteristics and cycling costs to determine the most-efficient mode for
operating multiple chillers.
• Run the chillers with the lowest operating costs to serve base load.
• Avoid oversizing -- match the connected load.
• Isolate off-line chillers and cooling towers.
• Establish a chiller efficiency-maintenance program. Start with an energy audit and follow-up, then make a chiller efficiency-maintenance program a part of your continuous energy management program.