Water Footprint of Bioethanol Production in Negros Occidental, Philippines

Abstract

 This study investigates the water scarcity implications of bioethanol production in Negros Occidental, Philippines. The water footprint (WF) of three bioethanol production scenarios was assessed, revealing respective values of 3,574 L L-1, 3,935 L L-1, and 4,293 L L-1 for Case 2 (molasses bioethanol), Case 3 (50% sugarcane and 50% molasses bioethanol), and Case 1 (sugarcane bioethanol). Predominantly, 99% of the total WF comes from sugarcane plantation activities, with the blue WF (freshwater use) accounting for a mere 1.3%, owing to predominantly rainfed sugarcane farms. Region VI, encompassing Negros Occidental, faces severe blue water scarcity at 41%, with projections indicating exacerbation unless water footprint mitigation strategies are implemented. Notably, the contribution of the bioethanol industry to the total WF of the region is only about 0.1%. Sensitivity analysis for varying sugarcane yield done revealed that increasing yield from 65 t ha-1 to 115 t ha-1 can significantly reduce WF to about 43%. This research underscores the need for water-efficient practices to address potential water scarcity of the region, while emphasizing the limited water scarcity impact of bioethanol industry.

Keywords: water footprint, water footprint assessment, water scarcity, bioethanol sugarcane, Negros Occidental, Philippines