The study has shown that WACS are technically feasible and that there are a number of types of WACS schemes that are economically and financially viable. These water use restrictions were imposed during the 1960 s as a consequence of the limited availability of water resources within Hong Kong and prior to the implementation of a reliable and continuous piped supply system of raw water from Guangdong Province. This has developed into a number of public and private sector seawater intakes pumphouses and pipeline systems, being constructed throughout the Territory for the direct supply of seawater for the air-conditioning chiller installations of large buildings.
Today there are approx.
The seawater is pumped to the water-cooled chillers located within each building plant room and is used to dissipate heat rejected from the chiller plant. The discharge of warmed water is returned to the sea via a separate discharge system with pressurised pipe network and sea outfall. The discharged warmed water also has the potential to be reused for building flushing water purposes. The seawater or freshwater is supplied to each building for use as make-up water for cooling towers normally located on the roof of each building. Alternatively, it may be discharged into public sewers if there is adequate spare capacity.