A branch-and-price algorithm for the single source capacitated plant location problem

This paper considers the Single Source Capacitated Plant Location Problem (SSCPLP). We propose an exact algorithm in which a column generation procedure for finding upper and lower bounds is incorporated within a Branch-and-Price framework. The bounding procedure exploits the structure of the problem by means of an iterative approach. At each iteration, a two-level optimization problem is considered. The two levels correspond with the two decisions to be taken: first, the selection of a subset of plants to be opened and then, the allocation of clients within the subset of open plants. The second level subproblem is solved using column generation. The algorithm has been tested with different sets of test problems and the obtained results are satisfactory.