In a typical mega shopping mall, 40 to 50% of their total energy consumption is by the mall’s air conditioning system. Nearly half of this is from the chillers. These provide chilled water to the Air Handling Units (AHU) to cool the air supplied to the occupied space.
The Challenge: Increased power costs and continuous compressor tripping at Kolour shopping mall
The Kolour Shopping Mall in Tsuen Wan, Hong Kong has been a major leisure and shopping stop for office workers and young families in the region since it opened in 1996. Recently, the mall’s management team had been made aware of an atypical increase in their electricity bills year-on-year. Investigations revealed the air conditioning system as the culprit.
Specifically, further investigation through their BMS system revealed the air-cooled centrifugal chillers were consuming an increase of almost 5 to 7% total energy usage every year along with repeated issues of compressor tripping.
After studying and analyzing the full cooling system, the conclusion was that the air-cooled condenser coil of the chiller had substantially deteriorated. This was the main cause of increase in the condenser refrigerant discharge temperature and pressure, resulting in a very high lift, which is the difference in pressure between the refrigerant in the condenser and the refrigerant in the evaporator. This was causing the chiller compressor to work substantially harder than its originally designed load, resulting in tripping, and consuming ever-increasing electrical energy.
The Solution: Installation of new condenser coils
Serck, along with JEC-Trane Hong Kong recommended the replacement of the condenser coils with new and improved condenser coils designed by Serck. The team supplied five sets of Serck KOTE coated (an anticorrosive coating) condenser coils for the five 330 Ton Trane centrifugal air-cooled chillers: a total of 15 brand new condenser coils, each more than 10m long. The old coils were removed and the new coils were installed by the expert team at JEC-Trane Hong Kong along with support and coordination from Serck.
The Results: A 15-month ROI, ongoing savings, and improved customer satisfaction
The on-site team at the Kolour mall measured the power consumed before and after the installation of the new condenser coils. Thanks to these benchmark measurements, it was easy to quantify the energy savings obtained from the replacement of the condenser coils. Overall, the customer saves approximately USD$60,000 per year in ongoing energy costs. This represents a return on investment of less than 1.5 years on the initial outlay cost of the Serck condenser coils. Apart from monetary savings on energy use, there are additional benefits to the site including improved air conditioning quality, lower ambient temperatures and more comfortable relative humidity, all resulting in high customer footfalls throughout the property.
To learn more about how Serck can assist with your climate control needs, including the highly effective Serck KOTE coating, contact us today.
