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Refrigerators remain among the greatest consumers of electrical energy in most homes, although mandated efficiency standards have decreased their energy consumption by some 80% in the past four decades. In the course of a day, one kitchen refrigerator removes 30 MJ of energy from its contents, in the process consuming 10 MJ of electrical energy. The electricity comes from a 40% efficient coal-fired power plant.
The electrical energy
- a. is used to run the light bulb inside the refrigerator.
- b. wouldn’t be necessary if the refrigerator had enough insulation.
- c. retains its high-quality status after the refrigerator has used it.
- d. ends up as waste heat rejected to the kitchen environment.
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