Trade Lane Megacities. Sobre la dimensión de la red / máquina logística global (2).

1. Tras darle un par de vueltas, diría que lo prioritario del juego naviero / canalero es resolver el caso de un sólo océano, una sola naviera y ¿ un par de puertos (origen y destino) ? con el supuesto de demanda de tráfico infinita.

Si este caso tiene solución finita y razonable (es decir no es una solución de tipo Atlántico-max, cosa que de momento desconozco), esta marca la dimensión para toda la red, pues entiendo que debe de ser trasladable a otros océanos, a cualquier océano, a canales y a estrechos.

El interés de un modelo tan mínimo, abstracto y sencillo es obviamente puramente teórico. En esta entrada, además del comentario anterior recopilamos bibliografía científica (no periodística salvo un par de casos) directamente relacionada con este problema. Antes recomiendo al lector ver esta presentación de noviembre de 2013, realizada por un profesor coreano, dónde aparecen proyecciones a futuro sobre el tamaño de los buques portacontenedores.  Si hoy ya navegan buques de 18.000 TEUs, se espera que en 2030 ya haya buques de 30.000 TEUs (sobre sus dimensiones hay varias posibilidades, un ejemplo: 553,8 x 82,1 x 20,6. No hace falta recordar que elque haya buques de tan gran tamaño no significa que todos los buques sean de este tamaño: hoy y  en todo momento la mayoría de los buques (si sigue una distribución de la población similar a la de hoy) serán de  pequeño tamaño, aunque seguramente, a  medida que la población global crezca, también crecerá el tamaño de los buques más  pequeños.  

_65943399_evolution_containerships_624v2

Fuente. Es un artículo de la BBC, con un buen título How much bigger can container ships get? aunque luego no contestan a la pregunta,  sino  que el tratamiento es anécdotico. Pero hablan explícitamente del juego naviero / canalero.

“Ships have been getting bigger for many years,” says Paul Davey from Hutchison Ports, which operates Felixstowe in the UK, one of the likely ports of call of the Triple E.

“The challenge for ports is to invest ahead of the shipping capacity coming on-stream, and to try and be one step ahead of the game.”

Overcapacity in the world’s ports means there is huge competition for business. Operators cannot afford to get left behind, says Marc Levinson, author of The Box – How the Shipping Container Made the World Smaller and the World Economy Bigger.

“The ports are placed in a difficult competitive position here because the carriers are basically saying to them, ‘If you don’t expand – if you don’t build new wharves and deepen the harbours and get high speed cranes, we’ll take our business someplace else.'”

These big beasts of the sea present ports with other challenges too.

Ship owners also want vessels to be unloaded and loaded within 24 hours, which has various knock-on effects. More space is needed to store the containers in the harbour, and onward connections by road, rail and ship need to be strengthened to cope with the huge surge in traffic.

“The history of container shipping involves ship lines taking huge gambles,” says Marc Levinson, who points to a trend for some American and European companies to move manufacturing back from Asia.

“There are a lot of people in the shipping industry who aren’t sure that Maersk is on the right track,” he says.

Jean-Paul Rodrigue at Hofstra University believes that big container ships like the Triple E will prove their value on specific trade routes, nonetheless.

“Each time a new generation comes along, there’s the argument ‘Oh is this going a little too far this time – is there enough port trade to justify this?'” he says.

“But each time the ship class was able to put itself in the system and provide a pretty good service.”

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2. LITERATURA CIENTÍFICA. 

¡¡ Un paper sobre exactamente esta misma temática !!…¡¡¡¡pero sin fecha!!!##@||!! Estimada  1998. Igual me ahorro el tener que pensar sobre este tema…Buscaré si hay algo más  actualizado, pero la fecha es interesante ya que nos permitirá saber si sus predicciones son certeras con respecto a los  actuales Tripe E de Maersk de 18.000TEUs.

_65888562_triple-e_2_edited

Fuente imagen: idem anterior.

Título. Economies of scale in larger container ships. Prof. Cullinane de la universidad Politécnica de Honk Kong y elCapitán de Buque Khanna. Accesible en PDF.

Joer, el modelo del paper, que está construido sobre otros modelos previos (añadiré bibliografía cuando los vaya leyendo) es bastante complicado…Pero creo que es exactamente el mismo enfoque (o similar): habla  de  las deseconomías de escala con el tamaño por el handling en puerto. Esto es diferente a los costes de inversión por redimensionar el puerto pero también muy relevante o más. Explicado más claramente:

“When ordered, most people talked about economy of scale of the
mega ships lowering shipping costs, lowering fuel consumption per unit
and lowering CO2 emissions…the other side of the ledger is higher
aggregation of risks per ship, longer port stays as the larger ships tax existing land side efficiencies, and an anticipated further shift from direct to indirect services, which add both time and cost of handling to the supply chain equation.”

“Some time sensitive shippers and forwarders are already starting to
look more closely at the potential negative impact of longer port stays.
The issue is that there can be a 2 or 3 day difference between the first container being discharged from a mega ship and the last container being discharged.” 

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De los mismos autores, otro posterior con otro título más sugerente.

Título. Economies of scale in large containerships: optimal size and geographical implications. De pago.

Abstract. 

In recent years, liner shipping has experienced an explosion in containership size. This is explained by the economies of scale in utilising such ships. This paper presents a model which quantifies the economies of scale in operating large containerships. A sensitivity analysis is conducted to test the effect of various input scenarios and the results analysed to determine optimal containership size with respect to different operational scenarios. Inferences are then drawn concerning the optimal deployment of the existing fleet of large containerships, likely future trends in containership size and deployment and the impact these trends will have upon container operations, logistical systems and ports.

Según el resumen de un autor posterior:

Cullinane and Khanna (1999) showed in their research that indeed economies of scale could be achieved by increasing the ship size. Based on data by Fairplay (1996) Cullinane and Khanna found that economies of scale could be achieved until a capacity of 8000 TEU. Different routes, and therefore distances, were also included in the analysis, to discover whether different distances affect the economies of scale that could be achieved. But on all three compared routes (Trans Atlantic, Trans Pacific and Europe-Far East) the trend was the same. As can be seen in Figure A6 in the appendix, on all three routes economies of scale can be achieved. The further the distance, the larger the economies of scale are. It should be noted that if additional feeder, transhipment and landside distribution costs are taken into account, the unit cost per TEU could increase again. This is illustrated by Sys et al. (2008). But in this section only the shipping liners are considered. The results of the study of Cullinane and Khanna suggest an optimal ship size of 8000 TEU. Cullinane and Khanna indicate however that larger ships could be economically viable, but the port productivity should increase first.

Se confirma por lo tanto que los resultados con respecto a un oceano serían trasladables, pero con matices. Por otra parte hay que tener mucho cuidado con el cálculo de costes.

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Otro de la misma fecha que el primero de los dos anteriores, 1998. Parece menos teórico.

Título. Economies of scale in container shipping.

Very large container ships are being built with the theoretical justification that they will produce economies of scale. It is clear, however. that the immediate result of the mega-ship buildings is an overtonnaging of the world’s major liner routes. As major operators have put newer and bigger ships in the water, they have significantly reduced the slot costs in the container trades to which these ships are assigned. However, operators have not reaped the benefits of those savings because most freight rates have dropped more than the cost reductions. The industry may never make an adequate return if everyone continues investing in new ships to drive costs down while simultaneously pushing rates down. Implenientation of economies of scale can not be a panacea per se. Carriers must find some way to return to profitability. Cooperation between the carricrs is highly desirable.

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En 2002 salió un autor crítico con las  economías de escala  en buquesporta contenedores, Martin Stopford. Es el autor de un libro que hemos  citado en la entrada anterior, Maritime Economy.

Título. Is the drive for ever bigger containership irresistible  ?. Presentación.

En la página 6 un gráfico muy interesante que muestra la evolución en el tamaño con el tiempo de diferentes tipos de buques: petroleros, gaseros, graneleros y de portacontenedores. Los  dos primeros mesetaron. Los otros dos siguen creciendo aunque la curva tiene  mucha más pendiente  para los portacontenedores.

Es un estudio / presentación bastante completo. Del mismo autor en 2008, pero sobre un tema más general.

De un autor anónimo:

Big ships are fascinating, especially really big ships like the Malacca-Maxes. But we need to keep a sense of balance. Stopford in his research discover following five points.

Firstly, economies of scale diminish, beyond 3000 TEU and over 8000 TEU the savings become immeasurably small.

Secondly, there are significant diseconomies due to the cost of dredging, congestion, distributing cargo from hubs and associated logistic difficulties.

Thirdly, there are massive economies to be made by upgrading ship sizes in the small and mid size trades.

Fourthly, the trading world is broadening and this will favor mid size ships.

Fifthly, a business dominated by logistics operators is likely to value the flexibility offered by smaller ships

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2004.

Título. The feasibility of mega container vessels.

Autor. Johannes Cornelius van Ham. Faculty of Technology, Policy and Management, Delft University of technology, The Netherlands

Abstract. The introduction of the container revolutionised maritime trade and shipping. Since 1956 container vessels have evolved from converted tankers and cargo ships, via full cellular container ships that could navigate the Panama Canal, to post-Panamax vessels with a capacity of approx. 8500 TEU (Twenty foot Equivalent Unit). Even bigger container ships (9600 TEU) are to be delivered soon. However, current technical and physical constraints such as propulsion and port limitations pose restrictions to further growth. Moreover, the diminishing economies of scale in ship costs are offset by the increase of other costs involved (e.g. port fees, terminal handling charges). Nevertheless, empirical research shows that the concept of mega container vessels is appealing and that, if available, most shipping lines will deploy such ships. So, the next generation container ships will probably consist of Suez-max vessels (up to 12,500 TEU) with twin propulsion systems. Albeit feasible from a technical point of view the ultimate 18,000 TEU container ship i.e. Mallaca-max has too many limitations to become popular.

Extracto.

3. Barriers to further growth.

The development of ever-larger container ships is, however, restricted by technical and physical constraints, logistical implications and economic aspects.

….

Port limitations
Of great importance for mega vessels are the harbour waters, berths and approach channels, there must be sufficient depth to accommodate the large vessels. A 16.5 meter deep port entrance allows access, albeit sometimes with minimal under-keel clearance, to nearly all containership now in existence. However, mega container carriers need up to 22 meters deep entrance channels. Currently, only a few ports are able to accommodate mega vessels. In the Far East and Europe the draft problem is less imperative than for (East Coast) U.S. ports where the question of how to achieve sufficient water depth is a vexing one. An aspect often forgotten in the discussion is the problem of ‘air draft’ i.e. the distance between the water surface and the highest point of the ship. At the moment very large containerships such as CSCL’s Asia have an air draft of 61.5 meter, which is close to the clearance of some bridges spanning the port entrance. The Bayonne Bridge in New York is a good example in this respect.

5. Conclusions

Undoubtedly, the trend of increasing ship size has not yet come to an end. Growing (Asian) markets require container capacity and shipping lines will provide it. Technically speaking mega carriers are feasible but from an economic point of view the benefits are small. Momentarily traditional concepts are stretched to its limits. Obviously, the new generation container ships are twin screw with two engines. If this is a success the next frontier is the Suez-max vessel up to approx. 12,500 TEU. The ultimate container vessel, the Mallaca-max probably has too many limitations to become a new standard.

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Uno de 2005.

Título. SHIPPING ECONOMIC ANALYSIS FOR ULTRA LARGE
CONTAINERSHIP. Chaug-Ing Professor. HSU National Chiao Tung University Taiwan y Yu-Ping HSIEH Ph.D. Candidate.Idem.

Abstract. 

Ultra large ships have the advantage of scale economies, but whether they successfully getting into service depend on cargo flow, shipping distance, port efficiency and constraints, etc. The study constructs a two-objective model to determine the optimal ship size and sailings frequency and analyze the shipping economies of ultra large ships by minimizing shipping costs and inventory costs. The results show the Pareto optimal solutions of the two-objective model and optimal ship size and sailings frequency with respect to each level of inventory costs and shipping costs. The sensitivity analysis shows the optimal ship tends to be large as route flow increases. Furthermore, the economies and possibility of using ultra large ships tend to increase, as port efficiency improves, shipping distance increases, the ports of call decreases, or the relative costs of large ships decrease.

Extracto. 

The size of containership tends to be large as world trade expands and cargo traffic grows. The development strides of containership size being large are great, especially after 1990. The largest ship in the world is 4,400 TEU in 1991, 6,000 TEU in 1996, and 7,500 TEU in 2003. The 8,000 TEU ship of OOCL (Orient Overseas Container Line) currently rewrites the record, and the ship is the largest ship among existing ships used. Moreover, large ships of 9,000+ TEU will be brought into Asia-Europe and Transpacific services soon in the near future, and ultra large ships of 12,500+ TEU are also expected to deliver in five to ten years (Frankel, 2002).

However, whether those large ships will provide services as well as expectation depend not only shipbuilding technology and port accommodation constraints are overcome but also those large ships must be more economic than existing ships used on current major routes. Although ultra large ships have the advantage of scale economies, that is, the average container cost decreases as ship size increases, it works only if cargo flow is large enough and sailings frequency is adequate for shippers. That is why, in reality, ocean carriers always alliance with each other or provide their services using hub-and-spoke networks to realize scale economies. Besides, key factors such as shipping distance, port efficiency, and the number of ports of call also influence the extent of scale economies. Therefore, this study takes those factors into account and constructs a model to analyze the shipping economies of ultra large ships and determine the minimum flows that realize scale economies.

Previous studies on ship size or ultra large ships were focused largely on economies of ship size. These studies indicate that economies of ship size occur at sea, while diseconomies of ship size are suffered in port, and that the choice of optimal ship size involves a balancing of the cost per ton at sea and the cost per ton in port (e.g., Jansson and Shneerson, 1987).

Recently, Cullinane and Khanna (1999,2000) indicate that the diseconomies of ship size in port are not apparent and the optimal ship size tends to be large as a result of improving port productivity. Moreover, McLellan (1997) provided detail discussions about the effects of larger ships on ports. Lim (1998) discussed that ships being large would impact all shipping industry. And Robinson (1998) forecasted the shipping service position of ultra large ships based on the trend of shipping development.

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Uno posterior de 2006 con una temática  similar.

Título. Routing, ship size, and sailing frequency decision-making for a maritime hub-and-spoke container network. Chaug-Ing HsuaYu-Ping Hsiehab

Abstract.

This study formulates a two-objective model to determine the optimal liner routing, ship size, and sailing frequency for container carriers by minimizing shipping costs and inventory costs. First, shipping and inventory cost functions are formulated using an analytical method. Then, based on a trade-off between shipping costs and inventory costs, Pareto optimal solutions of the two-objective model are determined. Not only can the optimal ship size and sailing frequency be determined for any route, but also the routing decision on whether to route containers through a hub or directly to their destination can be made in objective value space. Finally, the theoretical findings are applied to a case study, with highly reasonable results. The results show that the optimal routing, ship size, and sailing frequency with respect to each level of inventory costs and shipping costs can be determined using the proposed model. The optimal routing decision tends to be shipping the cargo through a hub as the hub charge is decreased or its efficiency improved. In addition, the proposed model not only provides a tool to analyze the trade-off between shipping costs and inventory costs, but it also provides flexibility on the decision-making for container carriers.

Claramente la frecuencia de navegación por una línea dada y el tamaño del buque, dado una demanda ilimitada están relacionadas inversamente.

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Y otro de 2006 también. Utilizan la teoría de juegos, pero en el abstract no queda claro cuales son los jugadores.

Título. The economic viability of container mega-shipsAkio ImaiabEtsuko NishimuraaStratos PapadimitrioucMiaojia Liua

Abstract.

In this study, we analyze the container mega-ship viability by considering competitive circumstances. We adopt a non-zero sum two-person game with two specific strategies based on different service network configurations for different ship sizes: hub-and-spoke for mega-ship and multi-port calling for conventional ship size. A shipping characteristic for each route is approximately optimized to set up pay-off (or profit) matrixes for both players. Throughout model applications for Asia–Europe and Asia–North America trades, the mega-ship is competitive in all scenarios for Asia–Europe, while it is viable for Asia–North America only when the freight rate and feeder costs are low.

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Uno de agosto de 2008.

Título. In Search of the Link between Ship Size and Operations.

Autor. Sys et all

A b s t r a c t.  Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted w ith a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of + 6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another. 

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Una tesis presentada en la Universidad de Rotterdam en 2011.

Título. The consequences of megaships.

Abstract.

In the last decades container ships became larger and larger. Carriers trying to achieve economies of scale by increasing the container ships. Some links in the supply chain face more challenges because of increasing container ships than others. But what are the implications and consequences of so called mega ships? In this paper the consequences for the carrier market, the consequences for the port authorities and the consequences for container terminals will be discussed. A short overview of relevant thoughts and expectations during three phases will be given. The most important limitations to large container ships are technical – and economical aspects.

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Uno de 2012.

Título. Scale and Diseconomies and Efficiencies of Liner Shipping

Autores: tres profesores de The Hong Kong Polytechnic University

In the context of liner shipping, carrying capacity can be seen as a key resource to strive for better firm performance. The liner shipping market nowadays has entered a phase in which liner shipping companies (LSCs) reap economies of scale. The concept of economies of scale has led the industry to grow by enlarging its capacity and firms allocate more ships to offer shipping services in the worldwide market. However, the results of enlarged capacity may be uncertain. By examining empirical data (from 1997 to 2008), this paper investigates the relationship between capacity and firm performance in the liner shipping industry and attempts to use an S-curve to describe their relationship. The findings suggest that the S-curve is robust. Furthermore, this study attempts to provide theoretical basis for shipping lines to determine the optimal carrying capacity.

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Uno artículo, que no es puramente científico sino publicado en una revista de una sociedad de clasificación ¿noruega?, recién salido del horno (21-3-2013) y aparentemente  el problema no se da por solucionado, al menos desde el punto de vista práctico. Autores: Audun Grimstad and Eivind Neumann-Larsen, DNV

Título. Ultra large container vessel- Can the economy of scale be quantified ?  

Resumen. After a period of rapid developments in the container-vessel sector, where yesterday’s deep-sea vessels are today’s feeders, will the ULCS size and capacity peak at or around the 18,000 TEU level and the attention shift towards different optimisation parameters, or will the increase in size continue? Owners and operators alike are looking for decisive evidence in either direction: will ever larger vessels mean ever increasing efficiency gains?

Extracto.

In all segments of bulk or commodity shipping, the focus will in principle be on economy of scale within the boundaries of physical and technological constraints – both for vessels and for the supporting infrastructure. In practice, however, the constraints and limitations posed by the other parts of the transport chain will restrict and check these developments; in a container shipping context this will typically be issues like the capacity of ports and terminals, shore cranes, hinterland infrastructure and the volume of cargo available for the trade in question.

Port developments for mainlane trades (FEA – EUR and FEA – US) in general seem to be keeping up with the growth in vessel size, driven by a projected cargo volume increase and competition between ports. Assuming, then, that the system as a whole will cope with continued growth in vessel size, what will the slot costs per TEU be as the vessel size increases?

Even this simplified approach seems to be able to point to at least three interesting trends.

Firstly, it is not surprising to find that the cost per TEU is strongly related to the vessel’s utilisation – as may also be seen from the figures. But it is of somewhat more interest to note that the difference in utilisation corresponding to a given slot cost is not very large between the vessels in our comparison. In other words, if the utilisation drops by only 3–5%, the cost advantage of a vessel that is “one size larger” will be evened out

Secondly, our findings show that the “slot cost parity” between a 14K and a 21K vessel corresponds to an up to 12% difference in utilisation; the difference will be reduced as utilisation rates fall. This means that you need as much as 5,000 additional TEUs per voyage for the 21K compared to the 14K vessel in order to have the same slot cost. Of course, the top slice or potential for profit should not be forgotten – the larger vessel will have a great number of available slots that may be sold at a healthy profit.

In short, you will always need to fill up your vessel to be profitable, no matter what its size. In addition, the number of ports at each end of the deep-sea leg cannot be too high, as any potential gains in utilisation are rapidly consumed by extra costs and time. After all, the main advantages of the larger vessel lie in the long legs and lower fuel cost per TEU.

In other words, it appears that the economy-of-scale effect is not necessarily as significant as has often been assumed.

The natural conclusion that can be drawn from this is that you need to be absolutely sure that you can fill your vessel in order to justify investing in ever larger ships – the slot cost reduction will not make up for or hedge against a significant drop in utilisation. 

Es un enfoque pragmático 100%.  Por su interés casi lo he copiado entero.

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Toda esta discusión está muy centrada en buques porta-contenedores, que son los que ahora mismo están experimentando una escalada en tamaño. Sin embargo hay otros buques que la experimentaron en su momento para pararse en una dimensión muy concreta, los petroleros. A esta clase perteneció el famoso Knock Nevis, ya desguazado.  Una muy buena página sobre los 10 mayores buques de la historia hasta el día de hoy. El Triple-E de Maersk ocupa la sexta plaza: los 5 primeros son petroleros, todos ya inactivos. El único activo ocupa la novena plaza, con 396 metros. El último es un crucero, el Oasis Class.

10.-Oasis-class-e1371170684798

En este enlace exploran esta cuestión para este tipo de  buques (los petroleros):

It is worth noting that tanker sizes have not increased since 1974 and you may pause to consider that, as well as economies, there can be diseconomies of scale. Whilst it is true that a ship of twice the size of another will not need twice as big a crew, or need twice the fuel consumption to drive it, there comes a time when big is no longer beautiful. Larger ships need larger ports, but a stage is eventually reached when a port cannot be deepened further or can only be deepened at prohibitive expense. Refineries or other industrial processes only need to be big enough to meet the demands of the markets they supply, so that facilities to take in far more raw material than they can handle is counter-productive. 
Thus the oil companies appear to have decided that VLCCs providing a steady supply, make more economic sense than over-large sporadic consignments, even though, in theory, the cost per ton-mile of oil in a bigger ship is lower. Nevertheless ULCCs are still being produced, the latest being Stena’s innovative and sophisticated VMax class which, unusually for large tankers, have twin engines and propellers making them more manoeuvrable and safer than many smaller ships.

 Y otro caso son los graneleros, caso estudiado en el mismo enlace.

Bulk carriers are another type that appear already to have found their optimum sizes, which are a complex combination of maximum economies of scale, coupled with the demands of the consumers, plus certain limitations imposed by the physical problems of exceeding certain dimensions. The sea is capable of being savage and there have been too many casualties to bulk carriers that experts say have been due to structural failure caused by a combination of design faults and poor maintenance.

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Hay un aspecto en toda esta literatura  que no se menciona pero parece relevante: el ahorro en mano de obra que suponen los barcos más grandes siempre y cuando estén automatizados.

He leído en alguno de ellos que un 18.000 TEU te cuesta lo mismo que 3 6.000 TEUs. Pero en personal necesitas tres veces menos, dado que con los mismos  trabajadores que atiendes un 18.000 TEU atiendes un 6.000 TEU (supongo que esto es así,  no lo se). Por lo tanto dada una misma capacidad, con buques de 18.000 TEUs necesita  1/3 de masa salarial que necesitarías con buques de 6.000 TEUs.   Si esto no es ahorro que me lo digan…

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