Problem P7.32 Suppose that the new type of computer power supply described in Pro...

Problem P7.32

Suppose that the new type of computer power supply described in Problem P7.31 costs an additional $5.

(a) At the cost of , after what period of time would the cost savings in electricity offset the power supply’s added cost?

(b) How often do you estimate that individuals and companies generally upgrade their desktop personal computers?

(c) From an economic standpoint, what recommendation would you make regarding the new type of power supply if you worked for a computer manufacturer?

Reference: Problem P7.31

When a desktop personal computer is operating, its power supply is able to convert only about 65% of the supplied electrical power into the direct current electricity that the computer’s internal electronic components require. The remainder of the energy is mostly lost as heat. On average, each of the estimated 233 million personal computers in the United States consumes 300 of energy each year.

(a) If the efficiency of the power supply could be increased to 80% by using a new type of power supply that is under development (a so called resonance-based switching-mode system), how much energy could be saved each year? Express your answer in the conventional units of for electricity.

(b) The United States produced 19.2 trillion of electrical energy in 2007. By what percentage would the nation’s electricity needs decrease?

(c) At the cost of , what would the cost savings be?