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A general definition of efficiency is the ratio between the useful energy or power output and the energy or power input - and can be expressed as

μ = Eo / Ei                                    (1)


μ = efficiency

Eo = useful energy or power output(Joules, W)

Ei = energy input or power (Joules, W)

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Related Topics


Work, heat and energy systems.

Related Documents

2nd Law of Thermodynamics

Entropy and disorder.

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The efficiency of the Carnot cycle.

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Performance and efficiency terminology related to heat pumps and air condition systems.

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Power is the rate at which work is done or energy converted.

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Power plants heat rates, thermal efficiencies, capacity factors, load factors, economic efficiencies, operational efficiencies and energy efficiencies.

Wind Power

Power generation from wind.

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