The building air conditioning task always presents itself as a major energy consumption issue. Approximately 30% of the energy consumed by office sector in Australia used for building air conditioning. A green and eco friendly air conditioning systems are an ideal alternative for the traditional conventional system with a potential to reduce the green house gases emissions resulted by the energy production. The aim of this project was to examine a solar air conditioning system with absorption chiller contributions in a small office building cooled in different thermal efficiency scenarios by demonstrating and evaluating specific architectural improvements to the basic model of the building. These improvements took the form of double-glazed windows, overhanging window shades, and a combination of double-glazed windows and overhanging shades in the environment of Sydney, NSW. The work is a useful guide for the building and air conditioning system design, modification, simulation and analysis, which can be a manual for engineers and energy analysers interested in energy efficiency field, as well as present a help to utilise energy simulation software’s such as TRNSYS and OpenStudio.