What is a SEER rating?
SEER (Seasonal Energy Efficiency Ratio) measures an air conditioning system's cooling efficiency across an entire cooling season, expressed as the total cooling output divided by total energy consumption in kilowatt-hours.
SEER stands for Seasonal Energy Efficiency Ratio. It measures how efficiently an air conditioning unit cools your home over the full cooling season, not just at a single outdoor temperature. The higher the SEER number, the more efficient the system. In Australia, SEER ratings typically range from around 3.0 to 10 or higher for residential units, depending on the type of system and age.
SEER differs fundamentally from EER (Energy Efficiency Ratio), which tests performance at a fixed outdoor temperature of 35 degrees Celsius. EER provides a snapshot of efficiency under one specific condition. SEER, by contrast, averages performance across the temperature variations a system experiences throughout the entire cooling season, from mild spring days to peak summer heat. This makes SEER a more realistic measure of year-round efficiency and operating costs for Perth homes.
When comparing air conditioning systems, SEER rating is the standard reference contractors and manufacturers use to indicate energy performance. Building standards and energy labels in Australia rely on SEER to help homeowners understand expected running costs. A higher SEER rating means lower energy bills and reduced power consumption, though it typically correlates with higher upfront equipment cost. Energy-efficient providers can explain how SEER ratings apply to your specific installation and climate needs.