Maintenanceis a process that makes a high-level contribution to the sustainability goal ofthe manufacturing facilities defined as uninterrupted, high-quality level,economic, efficient, reliable and environmentally friendly production. Theforemost stage of this important process is the maintenance planning and thefirst and indispensable phase of this stage is the maintenance strategyselection. When considering the maintenance processes which cause thesignificant costs due to production downtime, material, time and laborrequirements, assignment of the suitable maintenance strategies especially forthe critical equipment has great importance in terms of avoiding theunnecessary costs for the generation facility. Furthermore, maintenancestrategy optimization directly effects the goal of sustainable production inthe manufacturing facilities by providing to increase the faultless operatingtime of equipment and contribute to realize the reliable and high-qualitymanufacturing. In addition to these, this problem becomes more and moreimportant in the electricity generation plants which are in the group ofcontinuous production facilities, when the effects of energy on the society areconsidered. In this context in this study, among the electrical equipment whichare the most problematic group, the most critical ones in terms of the powerplant are determined by the AHP-TOPSIS combination in one of the big-scalehydroelectric power plants realize the 20% of Turkey’s electricity generation.Then, the most appropriate strategy combination from corrective, periodic,predictive and revision maintenance strategies is obtained by using theproposed integer programming model for these equipment groups. The use of thiscombination has resulted in an 80% improvement in generation downtimes andassociated costs.