What is power factor?
Power factor is the ratio of real power to apparent power. In AC circuits, PF less than 1.0 means some power is wasted. Many utilities penalize low PF.
Engineering
Electrical Power Calculator
Calculate power consumption, energy usage, and costs based on voltage and current inputs.
Power & Energy Analysis
Get instant calculations for electrical power, energy consumption, and associated costs.
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What this calculator does
The electrical power calculator computes real and apparent power consumption, energy usage, and operating costs. Power factor, which accounts for reactive power in AC systems, significantly affects real power and is crucial for industrial equipment efficiency analysis.
How it works
Using voltage, current, and power factor inputs, the calculator computes real power (P = V × I × PF), converts to energy (kWh) based on duration, and applies electricity rates for cost calculations.
Formula
Real Power = V × I × PF (watts). Apparent Power = V × I (VA). Reactive Power = √(S² - P²) (VAR). Energy = (P × hours) / 1000 (kWh). Cost = Energy × rate.
Tips for using this calculator
- Poor power factor (below 0.85) indicates reactive power waste—many utilities charge penalties
- Motors have PF around 0.7-0.9 depending on load
- Inductive loads require capacitive correction to improve PF
- Measure actual power factor before making financial decisions
- High-efficiency motors reduce costs 5-15%
Frequently asked questions
What's the difference between watts and volt-amperes?
Watts measure real power doing useful work. Volt-amperes measure total power supplied. The difference is reactive power that does no useful work.
How do I improve power factor?
Add capacitors to balance inductive loads. Proper load balancing across three-phase systems also helps. Many facilities use automatic correction units.