Energy conservation in building is the practice of saving energy
use without compromising occupant thermal comfort. ECMs often
provide better indoor air quality (IAQ) and enhance occupancies
productivity [1,2]. However, a cost penalty is experienced if poor
IAQ is traded for reduced energy consumption [3]. Building sectors
are responsible for approximately 42% of the world’s total annual
energy consumption [4]. Most of this energy is used for the provision
of lighting, HVAC systems and electricity based office appliances
[5]. In Australia 70% of the end use energy consumption in
non-residential buildings is devoted to HVAC and 15% to lighting
[6]. Buildings in the developed countries account for 50–60% of
electricity use [7,8]. Of the energy used for space conditioning,
65% is in the form of electricity [9]. Studies have reported that energy
savings of up to 30% can be achieved through retrofit options
in existing office and commercial buildings without compromising
the indoor comfort [10–14]. The operating costs of a building could
be improved if the lighting and HVAC system of the building can be
made more energy efficient.