Complete Guide to Power Consumption
The Power Consumption Estimator calculates kWh, cost, and carbon footprint for any load. Our free tool helps audit energy usage and reduce bills.
What is Power Consumption?
kWh = Power (kW) × Time (h). Real power = V × I × PF × phase factor. Our Power Consumption Estimator handles both phases.
Why Track Consumption?
Benefits:
- Save Money: Identify high users.
- Reduce Carbon: Lower emissions.
- Size Systems: Solar, generators.
- Audit Bills: Verify charges.
Use with Energy Cost and Solar Output.
Power Formulas
- Single-Phase: P = V × I × PF
- Three-Phase: P = √3 × V × I × PF
- kWh = P × hours × days / 1000
- Cost = kWh × rate
Common Appliance Ratings
| Appliance | Watts | kWh/Month (8h/day) |
|---|---|---|
| LED Bulb (10W) | 10 | 2.4 |
| AC (1 ton) | 1200 | 288 |
| Fridge | 150 | 108 |
| EV Charger (7kW) | 7000 | 1680 |
| Induction Motor (10HP) | 7500 | 1800 |
How to Reduce Usage
- Measure: Use plug meter.
- Replace: LEDs, Energy Star.
- Schedule: Off-peak.
- Improve PF: Capacitors.
- Insulate: HVAC efficiency.
Example: Office Building
480V 3-phase, 200A, PF 0.9, 10h/day, 30 days, $0.12/kWh.
- Power = 1.732 × 480 × 200 × 0.9 = 149.8 kW
- kWh = 149.8 × 10 × 30 = 44,940 kWh
- Cost = 44,940 × 0.12 = $5,393/month
Carbon Footprint
CO₂ = kWh × emission factor (lbs/kWh)
| Source | lbs CO₂/kWh |
|---|---|
| Coal | 2.2 |
| Natural Gas | 0.9 |
| Solar/Wind | 0.0 |
| US Average | 0.85 |
Practical Applications
Use for:
- Homes: Bill forecasting.
- Factories: Motor audits.
- Commercial: Lighting retrofits.
- Renewables: Battery sizing.
Tips
- Measure PF: Use meter.
- Off-Peak: Lower rates.
- Timers: Automate.
- Upgrade: Inverters, VFDs.
Common Mistakes
- Ignore PF: Overestimate kW.
- No Runtime: Assume 24h.
- Wrong Phase: Forget √3.
- Fixed Rate: Tiered billing.
Advanced
- Demand Charges: Peak kW.
- TOU Rates: Time-of-use.
- Net Metering: Solar credits.
- Smart Meters: Real-time data.
Conclusion
Tracking power consumption is the first step to efficiency. Our Power Consumption Estimator delivers instant kWh and cost insights. Pair with Energy Cost and Construction tools. Save energy with 1000 Calculators.