Cost Comparison of Container Handling Techniques

The factors affecting the economics of stacking and wheeled operations in container terminals are stated. By mathematical reasoning involving cost of land, cost of equipment and cost of labor, and their constituent factors inequalities were written and analyzed. From a small computer program which was written to calculate the relationship of the total cost of wheeled and that of stacking operations, graphs were developed for various values of top loader efficiency, number of days that containers stay in port, interest rates, and cost of land versus various values of the ratio between the total cost of stacking over the total cost of wheeled operations. In each graph, two areas were distinguished and separated by a horizontal line: the area above with values greater than one where wheeled operations are preferred and the area below with values of less than one where stacking operations are preferred. From studying these graphs, it is concluded that under the least efficient top loader operation (10 movements per day) the smallest interest rate and the smallest cost of land, six days of stay in port would be the longest time to justify wheeled operation.