Productivity differences in operating breakbulk reefer vessels: The case of a change in vessel hatch design in the banana trade

Loading and unloading breakbulk refrigerated (reefer) ships in scheduled services is crucial for port time. Disrupting the schedule integrity affects ports and ship owners/operators. Port time is based on historical operations data, and reefer ships follow a proforma schedule in each port of call to maintain this integrity.

The paper aims to identify factors affecting productivity of refrigerated breakbulk ships, develop a method to measure their output, and assess operational hurdles related to cargo-hold-hatch-cover design. Using data from 19 reefer vessels on 279 banana trade voyages, the study compares two classes of similar reefer ships but with different hatch designs.

The paper reviews literature on discharging breakbulk reefer vessels, explains proforma, and compares two vessels with different cargo-hold-hatch designs to highlight output variations associated with the respective vessels in the banana trade. Using statistical and economic analysis, it finds that a 74.2 % increase in output is needed to bridge the design differences. Vessel class differences lead to 164 % more time at berth, affecting schedule integrity, port time and charges. The study advises proforma negotiators and naval architects to consider vessel operation during design to optimize efficiency and return on investment.