📉 Economies of Scale
Definition: Economies of scale occur when a firm increases its output and its average cost (AC) per unit falls in the long run.
Average cost (AC) refresher
Average cost is the cost per unit of output. It is calculated as total cost ÷ quantity produced. When AC falls, each unit becomes cheaper to produce on average.
- AC = total cost ÷ output
- Economies of scale = output increases → AC falls
- This is a long-run idea: the firm can change plant size and all inputs
Why does AC fall as output rises?
When a firm grows, it can spread some costs over more units and also become more efficient. The result is lower cost per unit.
In exam answers, always write the chain: output rises → efficiency/spreading costs → AC falls.
🏭 Internal vs External Economies of Scale
The difference: Internal economies of scale reduce AC because the firm itself grows. External economies of scale reduce AC because the industry grows (firms benefit from the environment around them).
Internal economies (firm-level) — examples
- Technical: using more efficient machinery or production methods at larger scale → lower unit cost
- Purchasing: bulk buying inputs → discounts → lower input cost per unit
- Managerial: specialist managers improve productivity and reduce waste → lower AC
- Marketing: fixed advertising costs spread over more units → lower marketing cost per unit
- Financial: large firms may borrow at lower interest rates → lower finance costs
Internal economies = caused by growth of the firm. Use the phrase: specialisation, bulk buying, efficient capital.
External economies (industry-level) — examples
- Skilled labour pool: industry growth attracts trained workers → lower hiring/training costs
- Specialised suppliers: more input firms set up nearby → cheaper and more reliable inputs
- Shared infrastructure: better transport, broadband, ports → lower distribution and time costs
- Knowledge spillovers: ideas spread between firms (clusters) → faster innovation and efficiency
An external economy example: a growing tech cluster creates a local pool of experienced programmers. Firms spend less on recruitment and training, reducing AC.
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⚠️ Diseconomies of Scale + Competitiveness
Diseconomies of scale: Diseconomies of scale occur when a firm grows beyond an efficient size and its average cost (AC) rises.
Why can AC rise when firms get too big?
- Coordination problems: harder to organise production across departments/sites
- Communication breakdowns: slower decisions and mistakes increase costs
- Managerial inefficiency: layers of management reduce flexibility and productivity
- Loss of motivation: workers may feel less valued in very large firms, reducing productivity
- Bureaucracy: rules and procedures increase time and admin costs
Exam chain: firm grows too large → inefficiency/bureaucracy → productivity falls or waste rises → AC rises.
Link to competitiveness
If economies of scale lower AC, firms can often reduce prices while keeping profit margins. Lower prices can increase competitiveness, especially in competitive and international markets. However, if diseconomies of scale set in and AC rises, firms may lose cost advantage and become less competitive.
- Economies of scale → AC falls → lower prices possible → more competitive
- Diseconomies of scale → AC rises → higher prices or lower profits → less competitive