The study was conducted in humid-tropical Hong Kong situated
at the southern coast of China at latitude 22N and longitude
114E. The climate is largely regulated by the Asian monsoon system
with hot-humid summer characterized by high temperature
often exceeding 30 C in daytime and frequent heavy rainfalls.
The warm period extending from May to September coincides with
the rainy season, shedding about 2300 mm per annum. Winter is
relatively short and mild with temperature seldom falling below
10 C. The city has experienced a warming trend characterized by
rising average annual temperature, and increasing occurrence of
hot days (maximum exceeding 33 C in daytime) and hot nights
(minimum stays above 28 C in nighttime) [41]. Some 63% of the
total energy use in Hong Kong is consumed by buildings, with
air-conditioning taking the largest share [42,43]. The poor thermal
insulation of many buildings contributes to wasteful use of airconditioning
energy [44]. The community is finding ways to reduce
energy use of buildings.