1. What is Power Efficiency?

Power efficiency (η) is the ratio of output power to input power in a system, expressed as a percentage. It measures how effectively a system converts input energy into useful output energy.

2. How Does the Calculator Work?

The calculator uses the power efficiency formula:

Where:

• \( \eta \) — Efficiency (percentage)
• \( P_{out} \) — Output power (watts)
• \( P_{in} \) — Input power (watts)

Explanation: The formula calculates what percentage of input power is converted to useful output power. Higher percentages indicate more efficient systems.

3. Importance of Efficiency Calculation

Details: Calculating power efficiency is crucial for evaluating system performance, identifying energy losses, and improving energy conservation in electrical and mechanical systems.

4. Using the Calculator

Tips: Enter both output and input power in watts. Both values must be positive numbers. The result will be displayed as a percentage.

5. Frequently Asked Questions (FAQ)

Q1: What is considered good efficiency?
A: It depends on the system. For power supplies, >80% is good. For motors, >90% is excellent. Perfect efficiency (100%) is theoretically impossible.

Q2: Why is efficiency always less than 100%?
A: Due to inevitable energy losses like heat, friction, and resistance in real-world systems, as governed by the laws of thermodynamics.

Q3: How can I improve system efficiency?
A: Reduce losses by using better materials, optimizing design, reducing friction, improving insulation, and maintaining equipment properly.

Q4: Does efficiency vary with load?
A: Yes, most systems have peak efficiency at certain load levels, often between 50-80% of maximum capacity.

Q5: What's the difference between efficiency and power factor?
A: Efficiency measures energy conversion, while power factor measures how effectively current is being converted to useful work in AC systems.