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Energy Efficiency Formula:
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Energy efficiency (η) is a measure of how effectively a system converts input energy into useful output work. It is expressed as a percentage and indicates the proportion of input energy that is successfully transformed into the desired output.
The calculator uses the energy efficiency formula:
Where:
Explanation: The formula calculates the ratio of useful output work to total input work, multiplied by 100 to express it as a percentage. Higher percentages indicate more efficient energy conversion.
Details: Calculating energy efficiency is crucial for evaluating the performance of mechanical systems, electrical devices, and energy conversion processes. It helps identify energy losses and opportunities for improvement in various applications.
Tips: Enter both output work and input work in Joules. Ensure that output work is less than or equal to input work (efficiency cannot exceed 100%). All values must be positive numbers.
Q1: Why can't efficiency exceed 100%?
A: According to the law of conservation of energy, efficiency cannot exceed 100% as it would violate energy conservation principles, implying creation of energy.
Q2: What is considered good energy efficiency?
A: Good efficiency depends on the system, but generally values above 80-90% are considered excellent for most mechanical and electrical systems.
Q3: How does this relate to real-world applications?
A: This calculation is used in evaluating engines, motors, transformers, and various energy conversion systems to optimize performance and reduce energy waste.
Q4: What causes energy inefficiency?
A: Energy losses typically occur as heat due to friction, electrical resistance, sound, vibration, and other forms of energy dissipation.
Q5: Can efficiency be exactly 100%?
A: In practice, no system achieves 100% efficiency due to inevitable energy losses. Theoretical maximum efficiency is approached but never reached in real systems.