AC Power Consumption Basics
AC power consumption depends on capacity (tonnage), efficiency rating, and operating conditions.
Power Range by Tonnage
- 0.75 ton (9,000 BTU): 700-900 watts
- 1 ton (12,000 BTU): 900-1200 watts
- 1.5 ton (18,000 BTU): 1200-1800 watts
- 2 ton (24,000 BTU): 1800-2400 watts
Power Consumption Formula
Monthly Cost = Power (watts) × Hours per Day × 30 days × Electricity Rate ÷ 1000
Example Calculation
1.5 ton, 3-star AC (1500 watts), 8 hours daily, rate $0.12/unit:
1500 × 8 × 30 × 0.12 ÷ 1000 = $43.20/month
5-Star vs 3-Star AC Comparison
1.5 Ton AC (8 hours daily, $0.12/unit)
- 3-Star (1500W): $43.20/month
- 5-Star (1000W): $28.80/month
- Monthly savings: $14.40
- Annual savings: $172.80
Factors Affecting Power Draw
Usage Pattern
Morning: Lower power (room is cool) | Afternoon: Higher power (fighting heat gain) | Night: Lower power (temperature maintained)
Room Conditions
- Well-insulated room: Lower power
- Direct sunlight: Higher power
- Cool evening: Lower power
- Hot afternoon: Higher power
Temperature Setting
- 24°C: Higher power consumption
- 26°C: 10-15% lower power
- 28°C: 20-25% lower power
How to Reduce AC Electricity Usage
- Use fan instead of AC when possible
- Set temperature 2-3°C higher
- Use timer function
- Close doors and windows
- Use curtains to block sunlight
- Regular filter cleaning
- Annual professional service
Using an Energy Monitor
For accurate consumption tracking, use a power meter to measure your AC's actual watts at different times. This helps identify inefficiency issues.
Conclusion
Use our electricity cost calculator to estimate your specific AC's monthly costs. Invest in efficient ACs and usage habits to save significantly over time.