Analysis of Greenhouse Gas Emissions from a Combined Cycle Power Plant using RETScreen

Population growth and increasing energy demand have intensified fossil fuel consumption, resulting in higher greenhouse gas (GHG) emissions and environmental impacts. This study evaluates the environmental performance of the Saravan combined cycle power plant in Guilan Province, Iran, under two proposed seasonal fuel mix scenarios using RETScreen Clean Energy Management Software. Scenario 1 represents normal winter conditions, with natural gas used for ten months (March–December) and gasoil for two months (January–February), achieving total annual GHG emissions of 4,814,379 tCO₂ and a projected 30-year reduction of 71,882,453 tCO₂. Scenario 2 reflects severe winter conditions, with natural gas for eight months (April–November) and gasoil for four months (December–March), resulting in 5,018,646 tCO₂ of annual emissions and a projected 30-year reduction of 32,780,122 tCO₂. The analysis demonstrates that strategic seasonal adjustments in fuel usage—prioritizing natural gas when available and supplementing with gasoil during peak cold months—can substantially reduce GHG emissions while maintaining reliable electricity production. Furthermore, risk assessment indicates that the optimized seasonal fuel mixes provide economic benefits, with estimated savings from carbon shadow pricing of $119,804,088 for Scenario 1 and $54,633,537 for Scenario 2 over 30 years. Implementing such optimized seasonal fuel strategies enhances both environmental performance and operational flexibility, offering an effective approach for sustainable electricity generation and climate change mitigation in fossil fuel-based combined cycle power plants.