Time-of-use (TOU) electricity pricing has been applied in many countries around the world

to encourage manufacturers to reduce their electricity consumption from peak periods to

off-peak periods. This paper investigates a new model of Optimizing Electricity costs during

Integrated Scheduling of Jobs and Stochastic Preventive Maintenance under time of-use

(TOU) electricity pricing scheme in unrelated parallel machine, in which the electricity price

varies throughout a day. The problem lies in assigning a group of jobs, the flexible intervals

of preventive maintenance to a set of unrelated parallel machines and then scheduling of jobs

and flexible preventive maintenance on each separate machine so as to minimize the total

electricity cost. We build an improved continuous-time mixed-integer linear programming

(MILP) model for the problem. To the best of our knowledge, no papers considering both

production scheduling and Stochastic Preventive Maintenance under time of-use (TOU) electricity

pricing scheme with minimization total Electricity costs in unrelated parallel machine.

To evaluate the performance of this model, computational experiments are presented, and

numerical results are given using the software CPLEX and MATLAB with then discussed.