PROBLEM 11.24
MOTOR X FIRST COST = 2,500
MOTOR X SALVAGE VALUE = 0
MOTOR X EFFICIENCY = 90%
MOTOR Y FIRST COST = 1,750
MOTOR Y SALVAGE VALUE = 0
MOTOR Y EFFICIENCY = 85%
MOTOR Z FIRST COST = 1,000
MOTOR Z SALVAGE VALUE = 0
MOTOR Z EFFICIENCY = 80%
POWER COST PER KW-HR = $0.065
MARR = 12%
PLANNING HORIZON = 8
# HORSEPOWER/MOTOR = 15
# KILOWATTS/HORSEPOWER = 0.746
ANNUAL USAGE (HRS) = U
EUAC(X) = 2500(A|P 12%,8)+0.065*0.746*15*U/0.9 = 503.26+0.8081667U
EUAC(Y) = 1750(A|P 12%,8)+0.065*0.746*15*U/0.85 = 352.28+0.8557059U
EUAC(Z) = 1000(A|P 12%,8)+0.065*0.746*15*U/0.8 = 201.30+0.9091875U
Choose Motor Y for 2823 to 3176 hours.
Choose Motor Z for less than 2823 hours.
U EUAC(X) EUAC(Y) EUAC(Z) MINIMUM CHOICE EUAC(Y-Z) EUAC(X-Y)
0 $503.26 $352.28 $201.30 $201.30 Z $150.98 $150.98
100 $584.07 $437.85 $292.22 $292.22 Z $145.63 $146.22
200 $664.89 $523.42 $383.14 $383.14 Z $140.28 $141.47
300 $745.71 $608.99 $474.06 $474.06 Z $134.93 $136.72
400 $826.52 $694.56 $564.98 $564.98 Z $129.58 $131.96
500 $907.34 $780.13 $655.90 $655.90 Z $124.24 $127.21
600 $988.16 $865.70 $746.82 $746.82 Z $118.89 $122.45
700 $1,068.97 $951.27 $837.73 $837.73 Z $113.54 $117.70
800 $1,149.79 $1,036.84 $928.65 $928.65 Z $108.19 $112.95
900 $1,230.61 $1,122.42 $1,019.57 $1,019.57 Z $102.84 $108.19
1000 $1,311.42 $1,207.99 $1,110.49 $1,110.49 Z $97.50 $103.44
1100 $1,392.24 $1,293.56 $1,201.41 $1,201.41 Z $92.15 $98.68
1200 $1,473.06 $1,379.13 $1,292.33 $1,292.33 Z $86.80 $93.93
1300 $1,553.87 $1,464.70 $1,383.25 $1,383.25 Z $81.45 $89.18
1400 $1,634.69 $1,550.27 $1,474.17 $1,474.17 Z $76.10 $84.42
1500 $1,715.51 $1,635.84 $1,565.08 $1,565.08 Z $70.75 $79.67
1600 $1,796.32 $1,721.41 $1,656.00 $1,656.00 Z $65.41 $74.91
1700 $1,877.14 $1,806.98 $1,746.92 $1,746.92 Z $60.06 $70.16
1800 $1,957.96 $1,892.55 $1,837.84 $1,837.84 Z $54.71 $65.41
1900 $2,038.77 $1,978.12 $1,928.76 $1,928.76 Z $49.36 $60.65
2000 $2,119.59 $2,063.69 $2,019.68 $2,019.68 Z $44.01 $55.90
2100 $2,200.41 $2,149.26 $2,110.60 $2,110.60 Z $38.67 $51.14
2200 $2,281.22 $2,234.83 $2,201.52 $2,201.52 Z $33.32 $46.39
2300 $2,362.04 $2,320.40 $2,292.43 $2,292.43 Z $27.97 $41.64
2400 $2,442.86 $2,405.97 $2,383.35 $2,383.35 Z $22.62 $36.88
2500 $2,523.67 $2,491.54 $2,474.27 $2,474.27 Z $17.27 $32.13
2600 $2,604.49 $2,577.12 $2,565.19 $2,565.19 Z $11.92 $27.38
2700 $2,685.31 $2,662.69 $2,656.11 $2,656.11 Z $6.58 $22.62