Holistic Operation and Maintenance Excellence (HOME): Integrating Financial and Engineering Analysis to Determine Optimum O and M Strategies for a Power Plant during its Lifetime

Abstract

Today, there is an oversupply of 23.5 GW (47.7%) in the electricity system of Indonesia. PT.PLN, the state-owned electricity company, needs decision criteria to decide whether the power plant should be continue operated, rehabilitated or demolished. Base on the literature review, none of the frameworks in the world could be used to solve this problem. Therefore, this research proposed a new method or framework called HOME (Holistic Operation & Maintenance Excellence). The method has proposed and analysed in this research combines engineering analysis (efficiency and reliability) and economic analysis, which are total cost (acquisition cost, fuel cost, operation cost, and maintenance cost) and revenue. The objective is to define decision criteria to maximize the profit and minimize the cost has spent by a power plant. The final results are the decision criteria for a power plant, wheater to continue operated, rehabilitated, relocated, or demolished. A subcritical coal power plant, 400 MW, has been selected as a case study. Two scenarios of coals (LRC and HRC) and CF (79.46% and 60.96%) have been analyzed. Coal variation is used to evaluate its impact on efficiency and reliability, while CF change would represent the external and uncontrollable factor that impacts its revenue. The results showed that the thermal efficiency when using LRC (4,220 kcal/kg) reduced from 36.99% to 35.18% compared to HRC (4,917 kcal/kg), while the plant availability decreased from 97.93% to 97.45%. Nonetheless, the annualized profit when using LRC at the CF of 79.46% was 18.31 million USD/year, and it was a preferable option compared to 7.80 million USD/year when using HRC. Furthermore, the CF has predicted a reduction to 60.96%. In this situation, the power plant was better rehabilitated or relocated when it used HRC because it needs a minimum CF of 63.83% to get a break-even point (CFBEP). Conversely, the plant could continue to operate when LRC is used because CFBEP was 50.82%. Based on the analysis results, HOME is a good approach to determine and aid decision-making on the strategies required to operate and maintain a power plant comprehensively through its whole life cycle.