An Assessment Study on Greenhouse Gas Emission and Mitigation Measures: A Case Study of a Combined Cycle Power Plant in Rayong Province

Abstract

This study aims to investigate greenhouse gas (GHG) emissions resulting from various activities within a combined cycle power plant located in Rayong Province, Thailand. The assessment focuses on emissions data collected throughout the calendar year 2024, specifically from electricity generation processes. The evaluation follows the methodology outlined by the Thailand Greenhouse Gas Management Organization (Public Organization), which categorizes emissions into three scopes: (1) direct GHG emissions (Scope 1), (2) indirect GHG emissions from energy consumption (Scope 2), and (3) other indirect GHG emissions from external sources (Scope 3). The study utilizes both primary and secondary data, collected from the plant's operations between January and December 2024. The results reveal that the total GHG emissions from the plant's activities amounted to 424,240 metric tons of carbon dioxide equivalent (tCO₂eq), consisting of 331,513 tCO₂eq from direct emissions (Scope 1), 119 tCO₂eq from energy-related indirect emissions (Scope 2), and 92,608 tCO₂eq from other indirect sources (Scope 3).The analysis indicates that the majority of GHG emissions originate from the production of electricity, heat, and steam—both for internal use and for distribution to external users—as well as from energy losses during transmission. The primary GHGs emitted in these processes include carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). Therefore, it is recommended that the organization consider adopting appropriate mitigation strategies or technologies to reduce GHG emissions from its electricity generation processes, taking into account both the technical feasibility and cost-effectiveness of such measures.