These are an item over which the shipowner has less control, since they vary from port
to port, though big groups have a stronger negotiating position. Since port charges are
generally levied on the basis of the ship’s tonnage, this introduces an additional element
of economies of scale, since the port costs per TEU reduce as the ship gets bigger. In
Table 13.8, Section 5, we assume a reduction in the port costs per TEU from $22 for the
1,200 TEU ship to $10 for the 11,000 TEU ship. This creates an incentive to develop
ship designs with a low tonnage relative to capacity, especially for distribution trades
where the vessels make many port calls, encouraging designs with a low deadweight
and gross tonnage per TEU.