What is AC Star Rating?
Star rating is a standardized measure of an AC's energy efficiency. It's calculated based on SEER (Seasonal Energy Efficiency Ratio) and shows how much cooling you get per watt of electricity consumed.
Star Rating Scale
- 1 Star: Least efficient, highest electricity consumption
- 3 Stars: Average efficiency
- 5 Stars: Most efficient, lowest electricity consumption
How Ratings Are Determined
Ratings are based on laboratory tests measuring cooling output vs. power consumption. Tests follow standardized conditions to ensure fair comparison between brands.
SEER Explained
SEER = Total cooling output (BTU) / Total electricity input (Watts) over a season. Higher SEER = more efficient.
SEER to Star Rating Conversion
- SEER < 19: 1 Star
- SEER 19-22: 3 Stars
- SEER > 22: 5 Stars
Cost Impact
A 5-star 1.5 ton AC uses approximately 30-40% less electricity than a 3-star model, resulting in significant monthly savings.
Real-World Example
3-Star 1.5 Ton AC: Monthly bill ≈ $40 | 5-Star 1.5 Ton AC: Monthly bill ≈ $25 | Annual savings: ~$180
How to Check Star Rating
Look for the yellow Energy Guide label on AC units. It shows the star rating prominently along with estimated annual energy consumption.
Conclusion
Choose at least 3-star ACs for reasonable efficiency. If you use AC heavily, investing in 5-star models pays back within 2-3 years through electricity savings.