Abstract:
HVAC plants in buildings are generally started earlier than the building operation start
time. That is to absorb the stored thermal energy in the building and reach the set indoor
thermal condition by the time which the building operation is started. Cooling energy
required during this period is called Pre-cooling energy and the early plant running
time is called Pre- cooling time of the building. Thermal energy in buildings depends
on pre-defined factors and predicted factors. Pre-defined factors include building
envelope, envelope materials, type of HVAC system installed, Building interior,
lighting, other internal heat gain factors, building operation pattern etc. Predicted factors
include climatic condition in the region throughout the year. Due to the fact that precooling
time is determined by both pre-defined and predicted factors, a thermal
modeling study is more appropriate and recommended to assess the “pre-cooling
demand and time” of buildings. The focus on this research study is to prepare an
optimum “pre-cooling guidelines” for commercial buildings in Sri Lanka taking climatic
variations also into account. World Trade center, Colombo, the largest commercial
building in Sri Lanka was modeled in e-QUEST and results were analyzed with
Colombo climatic data throughout the year to study the pre-cooling requirements
(demand & time) and hence to derive a set of general pre-cooling guidelines applicable
to any commercial building in Colombo.
