Quote:
Most household appliances use electricity only when in use. Many microwave ovens, however, have built-in clocks and so use some electricity even when they are not in use. The clocks each consume about 45 kilowatt-hours per year.Therefore, households whose microwave oven has no built-in clock use 45 kilowatt-hours per year less, on average, than do comparable households microwave oven is otherwise similar but has a built-in clock.
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