testata inforMARE

20 ottobre 2020 Il quotidiano on-line per gli operatori e gli utenti del trasporto 02:49 GMT+2

1. Economies of Scale of the Ship

Ships intended for intermodal transport - with the sole (partial) exception of pallets - are characterized by complex technology and strong investment per unit of capacity. As such, they give rise to significant economies of scale while having relatively high speeds due to the traffic connections to be served. As in all other cases relative to the economic theory of optimum capacity - apart from draught limits for international waterways, the continental shelf and harbour depths, as well as limits in relation to the size and type of market (the magnitude of the flows of traffic to be served) - the economies of scale of ships intended for intermodal transport could also be unrestricted within the context of the intrinsic productive process of the ship itself. (This is with the obvious exception of large bulk carriers for liquid and dry cargoes, especially in relation to the costs linked to insuring against possible ecological disasters.)

Leaving aside the above factors, the potential for growth of the capacity of the ship, with the consequent benefits of economies of scale, is limited by the other element in the productive equation in shipping transport service - the port. Here, the rate of throughput of pier operations - i.e. of cargo unit handling - dictates the period of stay of the ship in port and reduces the possibility of exploiting the economies of scale of the ship itself.

The higher the rate of throughput - and, consequently, the more efficient, economic and well-organized the port - the greater the possibility of exploiting the economies of scale and, ceteris paribus, the lower the voyage costs per cargo unit.

But where the rate of throughput is high and increasing, this creates considerable and increasing requirements for space in the port area adjacent for the immediate stay of cargo units. In actual fact, such port areas normally tend to be lacking, due to the pressures for multifarious uses, so that they are only available at increasing cost; and, in the case of intermodal transport, they are specialized, i.e. not (as a rule) set aside for other uses, with the risk of the possible effects of "rationing" by the Port Authority.

The increase in space requirements in question may be reduced only where it is possible to regulate and accelerate the inflow and outflow of cargo units in port, and where the operations concerned (ranging from consolidation to deconsolidation, to the stay, to the repair of containers, to maintenance, etc.) are decentralized to the greatest possible extent away from the immediate port area.

The Ro-Ro system, which has the highest investments per unit of capacity of transport (decks, access ramps, volume lost on board, etc.), manages to offset this due to the possibility of rapid processing of cargo units in port and immediate decentralization of operations, which obviates the problem of lack of space and increasing costs (as is also the case with oil and pipes). The greater the frequency of stays in port, the greater this possibility becomes. As is common knowledge, these are the reasons for the comparative advantage of Ro-Ro on short and medium haul routes.

The generational qualitative leaps of container ships, for their part - together with the "transformations" and quantitative leaps in the market to be served, as occurred with "Round-the-World" services - are generally correlated with technical, organizational and territorial innovations enabling acceleration of the inflow and outflow of cargo units in port and decentralization of operations. It is sufficient, for example, to think of the principles "one trailer for every container" and "on wheel container" or the idea of silos for containers, of 15 to 20 years ago, or of the computerized handling and placement of containers of more recent times in order to appreciate this. Probably the most recent and obvious example - apart from "Octopus" technology - is provided by the experience of Post-Panamax ships and by the fact that:

  1. the possibility of success of ships of up to 6000 teu derives from a conspicuous precedent - that of the establishment of a railway landbridge from Los Angeles to New York for cargo originating in South East Asia and the Pacific - which has enabled cargo to by-pass the Panama Canal and ships to exceed the breadth limits imposed by that passage;
  2. the possibility of building broader ships has enabled the ships themselves to gain in terms of stability, thereby making less laborious and much faster the operations involved in placing containers on board and greatly increasing the speed of pier operations.

Indice Prima pagina Università degli Studi di Genova
Dipartimento di Economia - Sezione Trasporti

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