Operational blue water footprint and water deficit assessment of coal-fired power plants: case study in Malaysia

Abstract

Freshwater is an essential resource used to generate electricity at coal-fired power plants. Previous literature has shown that a few states in Malaysia will face a high risk of water stress. Hence, coal-fired power plants located at risk states are exposed to potential water risk. This study aims (i) to determine the operational blue water footprint at coal-fired power plant from 2009 until 2020; (ii) to assess the water stress index at Perak, Negeri Sembilan and Johor; and (iii) to compare the water deficit impact across three states. This study accounted the operational water footprint using Water Footprint Assessment Global Manual. The study boundary focuses on water consumption of generating electricity at operational level. The water stress index was assessed based on ratio of water demand and water availability at Perak, Negeri Sembilan and Johor watershed. Next water deficit impact was determined to compare the impact of operational blue water footprint on local water resources. Data for this study were collected from the state’s water authority, published literature, national reports, and statistics. Result of this study found the average operational blue water footprint recorded by coal-fired power plant located at Perak is 0.11 m³/MWh followed 0.09 m³/MWh (Johor) and 0.04 m³/MWh (Negeri Sembilan). Water stress index at Perak and Negeri Sembilan shows moderate water stress, whereas Johor indicates low water stress index. The water deficit result shows Perak has the highest total water deficit at 12,542,824 m³H₂Oeqn from 2009 to 2020. This is due to moderate water stress condition at Perak and the total blue water footprint of coal-fired power plant at Perak is 67% and 42% more as compared to Negeri Sembilan and Johor, respectively. The result from this study is useful in enhancing understanding of water consumption pattern at coal-fired power plant and its impact on state’s water resources for future electricity scenarios.