Energy, economics and environmental analysis for chillers in office buildings

Chillers consume a major share of total air conditioning energy use in commercial and industrial buildings for space conditioning to get thermal comfort for a country. In this paper, energy consumption by chillers has been estimated using data collected by walkthrough energy audit for Malaysian office buildings. It has been found that chillers use about 42,285MWh and 84,569MWh of electric energy for 50% and 100% loadings in an institutional buildings. As chillers are major energy users, energy savings measure such as use of energy efficient chillers and VSDs in chillers cooling load reductions have been applied to reduce their energy consumptions. It has been found that 90MWh-896MWh of energy can be saved for using energy efficient chillers for different percentage of loadings. Along with energy savings, US$57,314 as a bill savings can be achieved for high efficient chillers for 50% chillers loading. Study found that 35,975 MWh energy and US$2,302,431 bill can be saved for 60% of speed reductions using VSD. It was also found that payback periods for this energy saving option for chillers are economically viable. Along with energy savings, emission reductions and cost of avoided carbon associated with energy savings have been estimated and presented in this paper.