A bin activator has an initial cost of $34,000 and a salvage value described by
S =34,000 –3300k, where k is the number of years since the bin activator was purchased.
The net annual revenue is estimated by R = 5000 +600k. The equipment will have a
maximum useful life of 5 years. If the company’s MARR is 4% per year, when is the best
time to abandon the equipment?
EUAC is minimized at the end of year 5 of $3594.10. Therefore, the bin activator
should be kept for 5 years before it should be abandoned.
EUAC1=34,000 (A/P, 4%, 1) –5600 –600 (A/G, 4%, 1) – (30,700)(A/F, 4%, 1)
=34,000 (1.0400) –5600 –600(0) – (30,700)(1.0000)
= –940.00
EUAC2=34,000 (A/P, 4%, 2) –5600 –600 (A/G, 4%, 2) – (27,400)(A/F, 4%, 2)
=34,000 (0.5302) –5600 –600(0.4902) – (27,400)(0.4902)
= –1298.80
EUAC3= –1653.37
EUAC4= –2002.00
EUAC5= –2347.06
EUAC is minimized at the end of year 5. Therefore, the bin activator should be
kept for 5 years before it should be abandoned.
Lumberjack Power, operator of a nuclear power plant, is planning to replace its current
equipment with some that is more environmentally friendly. The old equipment has
annual operating expenses of $6750 and can be kept for 8 more years. The equipment will
have a salvage value of $4000, if sold 8 years from now, and has a current market value of
$24,000, if it is sold now. The new equipment has an initial cost of $62,000 and has
estimated annual operating expenses of $6250 each year. The estimated market value of
the new equipment is $19,000 after 8 years of operation. If the company’s MARR is 16%
per year, should the equipment be replaced? Use a study period of 8 years and the present
worth method.
PWD(16%) = –$52,099.30
PWC(16%) = –$83,352.50
The PW of the defender is greater than the PW of the challenger; the current
equipment should be retained for now.
Defender:
PWD(16%) = –24,000 –6750 (P/A, 16%, 8)+4000 (P/F, 16%, 8)
= –24,000 –6750 (4.3436) +4000 (0.3050)
= –52,099.30
Challenger:
PWC(16%) = –62,000 –6250 (P/A, 16%, 8) +19,000 (P/A, 16%, 8)
= –62,000 –6250 (4.3436) +19,000 (0.3050)
= –83,352.50
The PW of the defender is greater than the PW of the challenger; the current
equipment should be retained for now.