Cooling systems are used to help maintain a comfortable temperature. You can reduce the need for active cooling systems by improving the design of the dwelling; this could include adding shading, increasing ventilation, or lowering the solar heat gain coefficient (SHGC) of the window systems. If the cooling load in the thermal performance assessment is sufficiently low and it is realistic to not include a cooling system, then the highest-scoring option is "no cooling to be installed". However, if the cooling load is high, and you need to include a cooling system, you should try to select the most energy efficient option.
Apart from energy efficiency, other considerations include the upfront cost, maintenance costs, health and safety issues, reliability, noise, maintainability and life expectancy. For further guidance, refer to Energy Heating and Cooling.
NOTE: Ceiling fans are included in the thermal performance section of BASIX.