Life cycle environmental impacts and mitigation options for Bhumibol hydropower plant

Abstract

The Bhumibol hydropower plant's life cycle environmental impact assessment was conducted using SimaPro 8.0 LCA software, covering dam construction to power plant decommissioning, excluding dam removal and reclamation. The inventory data for LCA was directly provided by the power plant. The study found two main hot spot environmental impacts, climate change and water resource depletion, and a slightly impacted human toxicity-cancer effects. Climate change and human toxicity mainly occur during the construction phase, predominantly from concrete and metalwork steel. Replacing eco-concrete for future dam construction could mitigate GHG emissions by 52.2% and life cycle human toxicity by 55.0%. Recycling steel during power plant decommissioning at least 80% could mitigate GHG emissions by up to 84.0%. Integrating both options would also mitigate 74% human toxicity and up to 88.4% GHG emissions. Presently, the only options to mitigate impacts are during O&M, including water resource depletion. Increasing water resources by maximizing reforestation both at the dam upstream areas and the northern part of Thailand could help. Mitigating GHG emissions during O&M could be achieved by replacing existing cars and boats with electric and/or solar-powered vehicles, using carbon-neutral or biodegradable lubricants for transformers, and maximizing reforestation. Although no direct mitigation option has been reported, the study suggests implementing these options to minimize environmental impacts. These two mitigation options cannot be implemented at present and need to wait until the power plant decommissioning or a new dam construction.