Efficiency Calculator
Calculate energy efficiency, power conversion ratios, and machine performance
Energy Efficiency Analysis
Results
Efficiency Formula & Examples
Basic Efficiency Formula
Example 1: Electric Motor
Given:
• Electrical input: 1000 W
• Mechanical output: 850 W
Efficiency: η = (850/1000) × 100% = 85%
Example 2: Car Engine
Given:
• Fuel energy: 100 MJ
• Mechanical work: 25 MJ
Efficiency: η = (25/100) × 100% = 25%
Typical Efficiency Ranges
Electric Motors
85-95%
LED Lights
80-90%
Power Plants
35-45%
Car Engines
20-30%
Incandescent Bulbs
5-10%
Key Concepts
Energy Conservation
No machine can be 100% efficient
Energy Loss
Lost as heat, friction, sound
Useful Work
Desired output energy
Input Energy
Total energy supplied
Understanding Energy Efficiency
What is Energy Efficiency?
Energy efficiency is a measure of how effectively a machine, process, or system converts input energy into useful output energy. It's expressed as a percentage or decimal ratio between the useful energy output and the total energy input.
Why is Efficiency Important?
- •Reduces energy consumption and costs
- •Minimizes environmental impact
- •Improves system performance
- •Indicates design quality
Types of Efficiency
Mechanical Efficiency:
Ratio of mechanical work output to energy input
Thermal Efficiency:
Heat engines converting thermal energy to work
Electrical Efficiency:
Electrical power output to input ratio
Luminous Efficiency:
Light output per unit of electrical power
Energy Conservation and Efficiency Limits
Physical Limitations
- • Friction in moving parts
- • Heat loss to surroundings
- • Electrical resistance
- • Sound and vibration losses
- • Material imperfections
Theoretical Maximums
- • Carnot efficiency for heat engines
- • Quantum efficiency limits
- • Material property constraints
- • Thermodynamic limitations
- • Conservation laws