Analyzing Power Plant Capacity Expansion Alternatives with Multi-Criteria Decision-Making Methods

Abstract
Objective: The Marun Dam and Hydropower Plant, located in Khuzestan Province, Iran, represents the primary source of electricity supply for domestic and agricultural sectors within the Marun River Basin. In recent decades, increasing population growth, rapid urbanization, and the intensifying impacts of climate change have posed significant challenges to the reliability and sustainability of power generation in the region. Consequently, identifying optimal strategies for expanding electricity generation capacity has become a critical issue for regional energy planning. This study aims to prioritize alternative power generation development options in the Marun River Basin using a multi-criteria decision-making (MCDM) framework based on the Multi-Interval Multi-Criteria Trust Evaluation (TRUST) method.
Method: Based on the current operational conditions of the Marun Hydropower Plant and comprehensive field assessments, three development alternatives were proposed by domain experts: (i) integrating a solar power plant with the existing hydropower facility, (ii) adding a combined-cycle power plant to the hydropower system, and (iii) implementing a hybrid system comprising hydropower, solar, and combined-cycle power plants. To evaluate these alternatives, four main criteria—economic, environmental, technical, and energy supply security—along with ten corresponding sub-criteria were identified. The Criteria Importance Through Intercriteria Correlation (CRITIC) method was employed to determine objective weights for the criteria and sub-criteria, while the TRUST method was applied to rank the proposed alternatives.
Results: The CRITIC results indicate that the economic criterion holds the highest importance with a weight of 0.340, whereas greenhouse gas emissions emerge as the most influential sub-criterion with a weight of 0.156.
Conclusion: The TRUST-based ranking reveals that the hybrid configuration combining hydropower, solar, and combined-cycle power plants achieves the highest overall score (0.047), making it the most suitable option for enhancing electricity generation capacity at the Marun Power Plant. The findings underscore the advantages of integrated energy systems in improving supply reliability while balancing economic efficiency and environmental sustainability under climate-induced uncertainties.
 
 
 
English Extended Abstract
Introduction
Energy supply, particularly the reliable and efficient provision of electricity to various consumption sectors such as household, commercial, and agricultural uses, is widely recognized as a cornerstone of sustainable development.
Access to adequate electricity not only supports economic growth and social welfare but also enhances productivity, food security, and overall quality of life.
Consequently, ensuring a stable and resilient electricity supply system has become an essential priority for policymakers and energy planners.
In this context, the continuous monitoring, evaluation, and modernization of electricity generation technologies in power plants, while taking into account their economic feasibility, environmental impacts, technical performance, and social implications, represent one of the most effective and necessary measures for meeting increasing electricity demand and advancing long-term sustainable development objectives.
 
Method
The present study employed the multi-criteria decision-making (MCDM) approach of multi-interval multi-criteria trust evaluation (TRUST) to prioritize options for expanding electricity generation capacity in the Marun River Basin.
To this end, considering the operational conditions of the Marun Hydropower Plant as well as detailed field investigations, three development alternatives were proposed by energy experts:
(1) Integrating a solar power plant with the existing hydropower facility,
(2) Adding a combined-cycle power plant to the hydropower system,
(3) Developing a hybrid configuration that combines hydropower, solar, and combined-cycle power plants to enhance electricity generation capacity.
For the evaluation of these alternatives, a comprehensive set of main criteria—including economic, environmental, technical, and energy security criteria—along with ten corresponding sub-criteria was identified.
In the subsequent step, expert questionnaires were administered to determine the weights of the criteria and sub-criteria using the Criteria Importance Through Intercriteria Correlation (CRITIC) method, followed by the application of the TRUST method to rank the proposed alternatives. Finally, the aggregated weights of the sub-criteria and the priority ranking of electricity generation expansion alternatives were derived.
  
Results
The results obtained from the CRITIC method indicate that the economic criterion, with a weight of 0.340, is the most influential main criterion, while the greenhouse gas emissions sub-criterion, with a weight of 0.156, represents the most important sub-criterion.
Furthermore, the results of the TRUST method reveal that the hybrid configuration integrating hydropower, solar, and combined-cycle power plants achieves the highest overall score (0.047), thereby ranking as the most suitable alternative for increasing electricity generation capacity at the Marun Power Plant.
 
Conclusion
Currently, the water- and electricity-consuming sectors, including domestic, agricultural, and environmental sectors in the Marun River Basin, are facing numerous challenges in meeting existing and future demand.
Continuation of the current energy management practices may exacerbate these challenges and lead to more severe resource and supply crises in the region.
The findings of the present study can serve as a scientific basis for formulating electricity supply and energy planning policies in the coming years in the Marun Basin, in a manner that enhances the reliability and security of electricity supply.