Current scenario and potential of waste cooking oil as a feedstock for biodiesel production in Indonesia: Life cycle sustainability assessment (LCSA) review

WCO is a second-generation biofuel made up of accumulated free fatty acids, which can be used as feedstock for biodiesel production. The review aims to: (a) evaluate the sustainability of waste cooking oil (WCO) for biodiesel production in Indonesia using life cycle sustainability assessment (LCSA) methods; (b) explain the challenges, development, recommendation, and industrial potential of WCO for biodiesel production in Indonesia; and (c) determine the sustainability concept of WCO for biodiesel production. This study was carried out by reviewing papers related to LCSA which include Life Cycle Assessment (LCA), Life Cycle Cost Analysis (LCCA), and Social Life Cycle Assessment (SLCA). The review found that the WCO collection, pretreatment, and transesterification processes have the biggest environmental impact caused by the use of chemicals, catalysts, and electrical energy from fossil fuels. According to the LCCA results, WCO-based biodiesel production has a high economic potential and is more practicable due to lower raw material and production costs than biodiesel from edible and non-edible plants. Meanwhile, the SLCA aspect emphasizes that the WCO-based biodiesel industry must consider social indicators such as employment provision, human rights, human health impact, working conditions, local community impact, cultural heritage, socio-economic repercussions, governance, and large accident risk. There are several recommendations that can be made to develop WCO-based biodiesel, namely the government must demonstrate political commitment by promoting WCO as a national energy source feedstock. The sustainable concept has three pillars: environmental, economic, and social. These pillars must simultaneously direct every stage of the WCO production process. To produce high-quality biodiesel, the government must support all of these stages, establish regulations and governance for WCO supply and the WCO processing industry, and provide implementable R&D, adequate funding, and a campaign to raise awareness of the importance of reprocessing WCO into potentially profitable biodiesel in a circular economy.