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8. |
Capacity Planning Capacity comprises the resources to serve customers,
process information or make products and is a mix of the people, systems,
equipment and facilities needed to meet the services or products involved
(Hill, 2005). A definition of capacity should take into account both the
volume and the time over which capacity is available. Thus capacity can be
taken as a measure of an organisation’s ability to provide customers with
services or goods in the amount requested at the time requested. Capacity
decisions should be taken by firstly identifying capacity requirements and
then evaluating the alternative capacity plans generated. |
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8.1. |
Identifying
Capacity Requirements This stage consists of both estimating future customer
demand but also determining current capacity levels to meet that demand. |
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8.1.1. |
Measuring
Demand In a capacity planning context the business planning process is driven by two elements; the company strategy and forecasts of demand for the product/service the organisation is offering to the market. Demand forecasts will usually be developed by the marketing department and their accuracy will form an important element in the success of any capacity management plans implemented by operations. The demand forecast should express demand requirements in terms of the capacity constraints applicable to the organisation. This could be machine hours or worker hours as appropriate. The demand forecast should permit the operations manager to ensure that enough capacity is available to meet demand at a particular point in time, whilst minimising the cost of employing too much capacity for demand needs. The amount of capacity supplied should take into account the negative effects of losing an order due to too little capacity and the increase in costs on the competitiveness of the product in its market. Organisations must develop forecasts of the level of
demand they should be prepared to meet. The forecast provides a basis for
co-ordination of plans for activities in various parts of the organisation.
For example personnel employ the right amount of people, purchasing order the
right amount of material and finance can estimate the capital required for
the business. Forecasts can either be developed through a qualitative
approach or a quantitative approach |
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8.1.2 |
Measuring
Capacity When measuring capacity it must be considered that
capacity is not fixed but is a variable that is dependent on a number of
factors such as the product mix processed by the operation and machine setup
requirements. When the product mix can change then it can be more useful to
measure capacity in terms of input measures, which provides some indication of
the potential output. Also for planning purposes when demand is stated in
output terms it is necessary to convert input measures to an estimated output
measure. For example in hospitals which undertake a range of activities,
capacity is often measured in terms of beds available (an input) measure. An
output measure such as number of patients treated per week will be highly
dependent on the mix of activities the hospital performs. The theoretical
design capacity of an operation is rarely met due to such factors as maintenance
and machine setup time between different products so the effective capacity
is a more realistic measure. However this will also be above the level of
capacity which is available due to unplanned occurrences such as a machine
breakdown. |
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8.2. |
Evaluating Capacity Plans The organisation’s ability to reconcile capacity with
demand will be dependent on the amount of flexibility it possesses. Flexible
facilities allow organisations to adapt to changing customer needs in terms
of product range and varying demand and to cope with capacity shortfalls due
to equipment breakdown or component failure. The amount of flexibility should
be determined in the context of the organisation’s competitive strategy.
Methods for reconciling capacity and demand can be classified into three
‘pure’ strategies of level capacity, chase demand and demand management
although in practice a mix of these three strategies will be implemented. |
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8.2.1. |
Level Capacity This approach fixes capacity at a constant level throughout
the planning period regardless of fluctuations in forecast demand. This means
production is set at a fixed rate, usually to meet average demand and
inventory is used to absorb variations in demand. During periods of low
demand any overproduction can be transferred to finished goods inventory in
anticipation of sales at a later time period. The disadvantage of this
strategy is the cost of holding inventory and the cost of perishable items
that may have to be discarded. To avoid producing obsolete items firms will
try to create inventory for products which are relatively certain to be sold.
This strategy has limited value for perishable goods. For a service organisation
output cannot be stored as inventory so a level capacity plan involves
running at a uniformly high level of capacity. The drawback of this approach
is the cost of maintaining this high level of capacity although it could be
relevant when the cost of lost sales is particularly high, for example in a
high value retail outlet such as a luxury car outlet where every sale is very
profitable |
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8.2.2. |
Chase Demand This strategy seeks to change production capacity to match
the demand pattern over time. Capacity can be altered by various policies
such as changing the amount of part-time staff, changing the amount of staff
availability through overtime working, changing equipment levels and
subcontracting. The chase demand strategy is costly in terms of the costs of
changing staffing levels and overtime payments. The costs may be particularly
high in industries in which skills are scarce. Disadvantages of
subcontracting include reduced profit margin lost to the subcontractor, loss
of control, potentially longer lead times and the risk that the subcontractor
may decide to enter the same market. For these reasons a pure chase demand
strategy is more usually adopted by service operations which cannot store
their output and so make a level capacity plan less feasible. |
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8.2.3. |
Demand Management While the level capacity and chase demand strategies aim
to adjust capacity to match demand, the demand management strategy attempts
to adjust demand to meet available capacity. There are many ways this can be
done, but most will involve altering the marketing mix and will require co-ordination
with the marketing function. Demand Management strategies Include : |
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Varying the Price - During periods of low demand price
discounts can be used to stimulate the demand level. Conversely when demand
is higher than the capacity limit, price could be increased. |
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Provide increased marketing effort to product lines with
excess capacity. |
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Use advertising to increase sales during low demand
periods. |
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Use the existing process to develop alternative product
during low demand periods. |
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Offer instant delivery of product during low demand
periods |
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Use an appointment system to level out demand |