© wiley 20101 chapter 9– capacity planning & facility location define capacity planning and...

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© Wiley 2010 1 Planning & Facility Location Define capacity planning and location analysis Describe relationship between capacity planning and location, and their importance Explain the steps involved in capacity planning and location analysis Describe the decision support tools used for capacity planning Identify key factors in location analysis Describe the decision support tools used for location analysis

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© Wiley 2010 1

Chapter 9– Capacity Planning & Facility Location

Define capacity planning and location analysis Describe relationship between capacity

planning and location, and their importance Explain the steps involved in capacity

planning and location analysis Describe the decision support tools used for

capacity planning Identify key factors in location analysis Describe the decision support tools used for

location analysis

© Wiley 2010 2

Capacity planning Capacity is the maximum output rate of a facility Capacity planning is the process of establishing

the output rate that can be achieved at a facility: Capacity is usually purchased in “chunks” Strategic issues: how much and when to spend

capital for additional facility & equipment Tactical issues: workforce & inventory levels, &

day-to-day use of equipment

© Wiley 2010 3

Measuring Capacity Examples

There is no one best way to measure capacity Output measures like kegs per day are easier to understand With multiple products, inputs measures work better

Type of BusinessInput Measures of

CapacityOutput Measures

of Capacity

Car manufacturer Labor hours Cars per shift

Hospital Available beds Patients per month

Pizza parlor Labor hours Pizzas per day

Retail storeFloor space in square feet

Revenue per foot

© Wiley 2010 4

Measuring Available Capacity

Design capacity: Maximum output rate under ideal

conditions A bakery can make 30 custom cakes per

day when pushed at holiday time Effective capacity:

Maximum output rate under normal (realistic) conditions

On the average this bakery can make 20 custom cakes per day

© Wiley 2010 5

Measuring Effectiveness of Capacity Use Measures how much of the available

capacity is actually being used:

Measures effectiveness Use either effective or design

capacity in denominator

100%capacity

rateoutput actualnUtilizatio

© Wiley 2010 6

Example of Computing Capacity Utilization: A bakery’s design capacity and effective capacity are 30 and 20 cakes per day, respectively. Currently the bakery is producing 28 cakes per day. What is the bakery’s capacity utilization relative to both design and effective capacity?

93%(100%)30

28(100%)

capacity design

output actual nUtilizatio

140%(100%)20

28(100%)

capacity effective

output actual nUtilizatio

design

effective

The current utilization is only slightly below its design capacity and considerably above its effective capacity

The bakery can only operate at this level for a short period of time

© Wiley 2010 7

Capacity Considerations The Best Operating Level is the output that results

in the lowest average unit cost Economies of Scale:

Where the cost per unit of output drops as volume of output increases

Spread the fixed costs of buildings & equipment over multiple units, allow bulk purchasing & handling of material

Diseconomies of Scale: Where the cost per unit rises as volume increases Often caused by congestion (overwhelming the process with

too much work-in-process) and scheduling complexity

© Wiley 2010 8

Best Operating Level and Size

Alternative 1: Purchase one large facility, requiring one large initial investment Alternative 2: Add capacity incrementally in smaller chunks as needed

© Wiley 2010 9

Other Capacity Considerations Focused factories:

Small, specialized facilities with limited objectives

Plant within a plant (PWP): Segmenting larger operations into

smaller operating units with focused objectives

Subcontractor networks: Outsource non-core items to free up

capacity for what you do well

© Wiley 2010 10

Making Capacity Planning Decisions

The three-step procedure for capacity planning decisions:

1. Identify Capacity Requirements

2. Develop Capacity Alternatives

3. Evaluate Capacity Alternatives

© Wiley 2010 11

Identifying capacity requirements

Forecasting Capacity: Long-term capacity requirements based on future demand Identifying future demand based on forecasting Forecasting, at this level, relies on qualitative forecast

models Executive opinion Delphi method

Forecast and capacity decisions must include strategic implications

Capacity cushions Plan to underutilize capacity to provide flexibility

Strategic Implications How much capacity a competitor might have Potential for overcapacity in industry is a possible hazard

© Wiley 2010 12

Developing & Evaluating Capacity Alternatives

Capacity alternatives include Could do nothing, expand large now (may included capacity

cushion), or expand small now with option to add later

Use decision support aids to evaluate decisions (decision tree: most popular)

© Wiley 2010 13

Decision trees

Diagramming technique which uses Decision (square) nodes– points in time when

decisions are made. Decision alternatives branches of the tree from the decision nodes.Pruning of the tree (decision has to be made) here.

Chance (circular) nodes – where different possible outcomes (with different probabilities) emanate. No decisions made here.

© Wiley 2010 14

Decision tree diagrams

Decision trees developed by Drawing from left to right Use squares to indicate decision points Use circles to indicate chance events Write the probability of each chance by the

chance (sum of associated chances = 100%)

Write each alternative outcome in the right margin

© Wiley 2010 15

Example Using Decision Trees: A restaurant owner has determined that she needs to expand her facility. The alternatives are to expand large now and risk smaller demand, or expand on a smaller scale now knowing that she might need to expand again in three years. Which alternative would be most attractive? (see notes)

© Wiley 2010 16

Evaluating the Decision Tree

Decision tree analysis utilizes expected value analysis (EVA)

EVA is a weighted average of the chance events Sum of (Probability of occurrence * value of the

chance event outcome) Refer to previous slide

At decision point 2, choose to expand to maximize profits ($200,000 > $150,000)

Calculate expected value of small expansion: EVsmall = 0.30($80,000) + 0.70($200,000) = $164,000

© Wiley 2010 17

Evaluating the Decision Tree con’t

Calculate expected value of large expansion: EVlarge = 0.30($50,000) + 0.70($300,000) =

$225,000 At decision point 1, compare alternatives &

choose the large expansion to maximize the expected profit: $225,000 > $164,000

Choose large expansion despite the fact that there is a 30% chance it’s the worst decision: Take the calculated risk!

© Wiley 2010 18

Location Analysis Facility location is the process of identifying the best geographic location for a service or production facility. Factors affecting location Decisions are:

Proximity to source of supply: Reduce transportation costs of perishable or

bulky raw materials Proximity to customers:

High population areas, close to JIT partners Proximity to labor:

Local wage rates, attitude toward unions, availability of special skills (silicon valley)

© Wiley 2010 19

Other Location Factors Community considerations:

Local community’s attitude toward the facility (prisons, utility plants, etc.)

Site considerations: Local zoning & taxes, access to utilities, etc.

Quality-of-life issues: Climate, cultural attractions, commuting time, etc.

Other considerations: Options for future expansion, local competition,

etc.

© Wiley 2010 20

Globalization – Should Firm Go Global?

Globalization is the process of locating facilities around the world

Potential advantages: Inside track to foreign markets, avoid trade barriers, gain

access to cheaper labor Potential disadvantages:

Political risks may increase, loss of control of proprietary technology, local infrastructure (roads & utilities) may be inadequate, high inflation

Other issues to consider: Language barriers, different laws & regulations, different

business cultures

© Wiley 2010 21

Making Location DecisionsAnalysis should follow 3 step process:

1. Identify dominant location factors2. Develop location alternatives3. Evaluate locations alternatives

Procedures for evaluation location alternatives include

Factor rating method Load-distance model Center of gravity approach Break-even analysis Transportation method

© Wiley 2010 22

Factor Rating Example

© Wiley 2010 23

A Load-Distance Model Example: Matrix Manufacturing is considering where to locate its warehouse in order to service its four Ohio stores located in Cleveland, Cincinnati, Columbus, Dayton. Two sites are being considered; Mansfield and Springfield, Ohio. Use the load-distance model to make the decision.

Calculate the rectilinear distance:

Multiply by the number of loads between each site and the

four cities

miles 4515401030dAB

© Wiley 2010 24

Calculating the Load-Distance Score for Springfield vs. Mansfield

The load-distance score for Mansfield is higher than for Springfield. The warehouse should be located in Springfield.

Computing the Load-Distance Score for SpringfieldCity Load Distance ld

Cleveland 15 20.5 307.5Columbus 10 4.5 45Cincinnati 12 7.5 90Dayton 4 3.5 14

Total Load-Distance Score(456.5)

Computing the Load-Distance Score for MansfieldCity Load Distance ld

Cleveland 15 8 120Columbus 10 8 80Cincinnati 12 20 240Dayton 4 16 64

Total Load-Distance Score(504)

© Wiley 2010 25

The Center of Gravity Approach

This approach requires that the analyst find the center of gravity of the geographic area being considered

Computing the Center of Gravity for Matrix Manufacturing

Is there another possible warehouse location closer to the C.G. that should be considered?? Why?

10.641

436

l

YlY ; 7.9

41

325

l

XlX

i

iic.g.

i

iic.g.

Computing the Center of Gravity for Matrix ManufacturingCoordinates Load

Location (X,Y) (li) lixi liyi

Cleveland (11,22) 15 165 330Columbus (10,7) 10 165 70Cincinnati (4,1) 12 165 12

Dayton (3,6) 4 165 24Total 41 325 436

© Wiley 2010 26

Break-Even Analysis Break-even analysis computes the amount of goods

required to be sold to just cover costs Break-even analysis includes fixed and variable costs Break-even analysis can be used for location analysis

especially when the costs of each location are known

Step 1: For each location, determine the fixed and variable costsStep 2: Plot the total costs for each location on one

graphStep 3: Identify ranges of output for which each

location has the lowest total costStep 4: Solve algebraically for the break-even points over the identified ranges

© Wiley 2010 27

Break-Even Analysis

Remember the break even equations used for calculation total cost of each location and for calculating the breakeven quantity Q.

Total cost = F + cQ Total revenue = pQ Break-even is where Total Revenue = Total Cost

Q = F/(p-c)Q = break-even quantityp = price/unitc = variable cost/unitF = fixed cost

© Wiley 2010 28

Example using Break-even Analysis: Clean-Clothes Cleaners is considering four possible sites for its new operation. They expect to clean 10,000 garments. The table and graph below are used for the analysis.

Example 9.6 Using Break-Even AnalysisLocation Fixed Cost Variable Cost Total Cost

A $350,000 $ 5(10,000) $400,000B $170,000 $25(10,000) $420,000C $100,000 $40(10,000) $500,000D $250,000 $20(10,000) $450,000

© Wiley 2010 29

The Transportation Method

Can be used to solve specific location problems Is discussed in detail in the supplement to this

text Could be used to evaluate the cost impact of

adding potential location sites to the network of existing facilities

Could also be used to evaluate adding multiple new sites or completely redesigning the network

© Wiley 2010 30

Chapter 9 Highlights Capacity planning is deciding on the maximum output rate of a facility Location analysis is deciding on the best location for a facility Capacity planning and location analysis decision are often made

simultaneously because the location of the facility is usually related to its capacity.

In capacity planning and location analyses, managers must follow three-step process. The steps are assessing needs, developing alternatives, and evaluating alternatives.

To choose between capacity planning alternatives managers may use decision trees.

Key factors in location analysis included proximity to customers, suppliers, source of labor, community attitude, and quality of life issues .

Factor rating is a tool that helps managers evaluate qualitative factors. The load-distance model and center of gravity approach evaluate the location decision based on distance. Break-even analysis is used to evaluate location decisions based on cost values. The transportation method is an excellent tool for evaluating the cost impact of adding sites to the network of current facilities.