Short-term maintenance scheduling for utility systems

Purpose - The purpose of this study is to optimize short-term maintenance scheduling of utility systems satisfying network constraints.Design methodology approach - A mathematical programming model with network constraints is presented.Findings - There are some cases in which the maintenance of a certain unit affects the operations of non-maintenance units. The schedule should be evaluated by labor cost, material cost and opportunity costs. However, most utility systems contain dual-directional flows, making the interdependency of the units an unstable element. In such systems, the dependency between one unit and the other should be adjusted depending on the conditions.Practical implications - Power, steam and water are distributed by utility systems. Unit maintenance affects the operation of non-maintenance units within the networks. Effective short-term maintenance scheduling of utility systems must work within these network constraints. Unlike conventional scheduling methods, the excessive concentration of maintenance tasks should be controlled to reduce supply losses. A mixed integer linear programming model was utilized for identifying the solution of the problem. The present model can be applied to various utility systems.Originality value - The model can address alternative flows to reflect current conditions. Binary variables are applied to preserve the consistency of flow balances. The logic tree analysis expressed the current flow balances using linear constraints. The effectiveness of the model was supported by case examples.