An electrical energy audit indicates that the motor control center consumption is 8*10^6 kWh per year. By using high-efficiency motors a savings of 15 percent can be achieved. The additional cost for these motors is about $80,000. Assuming that the average energy charge is $0.08 per kWh, is the expentidure justified based on a minimum rate of return of 18 percent before taxes? Assume a 20-year life cycle and use the present worth, annual cost and rate of return methods.