In: Economics
HopHeart Brewery is considering 3 different bottling machines. It is expected that each machine will be replaceable at the same cost when their useful life ends. The details of the machines are as follows: Machine X has a useful life of 6 years. It costs $10,000 to purchase and $2,000 per year to maintain. Machine Y has a useful life of 12 years. It costs $15,000 to purchase, and $1,000 per year to maintain. Machine Z has a useful life of 8 years. It costs $20,000 to purchase, and $200 per year to maintain. a) What is the appropriate planning horizon for analyzing these choices? Correct: Your answer is correct. years b) Using the planning horizon from part a, analyze the present worth of the cost of each alternative if HopHeart has a MARR of 8.5%/year. Machine X _____________ Machine Y _____________ Machine Z _____________
ANSWER:
i am solving this in 2 ways , first in the planning horizon which includes lcm to find the common no of years and secondly the present worth in there actucal years, so that you can understand the difference.
1) Since the planning horizon is years , therefore we will have to find the lcm of the three useful lives that is the lcm of(6,12,8) which is 24.
i = 8.5% , n = 24 years
since the table of 8.5% interest is not available , therefore i will solve it in excel.
cash flows = initial cost in year 0 + maintenance cost in year 0 + ..... + initial cost in year 24 + maintenance cost in year 24
machine x | |||||||||||||||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
initial cost | 10,000 | 10,000 | 10,000 | 10,000 | |||||||||||||||||||||
maintenance cost | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | |
cash flows | 10,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 12,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 12,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 12,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 |
npv | 42,397.5067646209 | ||||||||||||||||||||||||
machine y | |||||||||||||||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
initial cost | 15,000 | 15,000 | |||||||||||||||||||||||
maintenance cost | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | |
cash flows | 15,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 16,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 |
npv | 30,739.6222562305 | ||||||||||||||||||||||||
machine z | |||||||||||||||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
initial cost | 20,000 | 20,000 | 20,000 | ||||||||||||||||||||||
maintenance cost | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | |
cash flows | 20,000 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 20,200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 20,200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 |
npv | 37,856.1418290675 |
Since the npv of machine b is the lowest therefore we will choose machine y.
2) pw of each machine via there original lives.
machine x | |||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | ||||||
initial cost | 10,000 | ||||||||||||
maintenance cost | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | |||||||
cash flows | 10,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | 2,000 | ||||||
npv | 19,107.1743390960 | ||||||||||||
machine y | |||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
initial cost | 15,000 | ||||||||||||
maintenance cost | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | |
cash flows | 15,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 | 1,000 |
npv | 22,344.6860696889 | ||||||||||||
machine z | |||||||||||||
years | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | ||||
initial cost | 20,000 | ||||||||||||
maintenance cost | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | |||||
cash flows | 20,000 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | 200 | ||||
npv | 21,127.8365936075 |
Had we not chosen the planning horizon of years , we would have chosen machine x as it has the lowest present worth but since the planning horizon is for years , we have to find the lcm and then choose the option y.
the 2nd part is for your better understanding , please use the values in part 1 for the present worth ( although both are correct but part 1 has taken horizon planning while part 2 is without horizon planning,)
in excel we find the present worth by using the =npv(rate,cash flows of each year) + initial year cash flow