A refrigerator is rated at 200 W: why not multiply by twenty-four hours?
Equipment that cycles or adjusts its power does not necessarily operate at its nameplate rating continuously. Distinguish rated power from average energy use.
Electricity cost calculator →Compare two operating assumptions
Continuous operation at 200 W for twenty-four hours would use 4.8 kWh daily. An illustrative assumption of eight equivalent full-power hours would instead use 1.6 kWh. The second value is not a claim about every refrigerator; it demonstrates how the operating-time assumption changes the estimate. The actual duty pattern must come from relevant evidence.
Prefer suitable measured consumption when available
An appropriate energy meter or manufacturer energy-use information can provide a better basis, provided the test conditions are understood. If the available figure is already kWh per day, do not enter it into a watts field as though it were power. Preserve the physical meaning of each input rather than forcing every number into the same form.
Calculate time-of-use tariffs in separate segments
If one day includes 1 kWh priced at 0.3 and 2 kWh priced at 0.1, the energy cost is 0.5, not 0.9 from applying the higher rate to everything. This calculator uses one price per calculation, so calculate the segments separately and add their costs. Fixed charges and taxes still require separate treatment. An average price is useful only when weighted by the energy actually charged at each rate.
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