How this calculator works
Conversion efficiency compares useful output with supplied energy over the same interval. All energies cross the same chosen system boundary. The remainder may leave as unwanted heat, sound or other forms; it is not destroyed. For a heat pump, delivered heat includes energy moved from the surroundings, so its coefficient of performance is a different measure and may exceed one.
Formula
eta = Euseful/Ein; Euseful = eta Ein; Ein = Euseful/eta; Eloss = Ein - Euseful.
Worked example
A device using 1000 J to supply 750 J of useful work is 75% efficient and leaves 250 J as other outputs. Supplying 600 J at 60% efficiency produces 360 J useful output.
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Frequently asked questions
Can conversion efficiency exceed 100%?
Not with all energy inputs included and useful output defined consistently.
Can I compare powers instead?
Yes, when both powers describe the same steady operating interval; their ratio gives the same efficiency.
What does the loss output mean?
It is energy excluded from the chosen useful output, rather than energy disappearing.