Evaluation of strategies for utilizing rice husk based on life cycle cost analysis in relation to Greenhouse Gas emissions in An Giang province, Vietnam

To evaluate the cost effectiveness of rice husk utilization, a life cycle cost analysis was conducted for 18 scenarios developed in a previous study. The allocation of fuels other than rice husks was decided on the basis of current demand for and supply of rice husks. The production of rice husk briquettes is also discussed as a means of circumventing problems arising from the bulk of the material. In the power generation scenarios, differences between two generating capacities (5 and 30 MW) were analyzed. Costs savings are possible by using rice husk to replace fossil fuels for cooking. With regard to power generation, operation on a 30-MW scale by combustion of all available rice husk was identified as the most economically efficient scenario, followed by small-scale gasification scenarios (5 MW). The combustion of rice husk briquettes for power generation appeared to be less cost-efficient than direct combustion, whereas large-scale gasification scenarios and pyrolysis scenarios give rise to increases in cost compared with the baseline. When both GHG abatement and costs are taken into consideration, suitable scenarios that are practicable involve the use of rice husk for cooking, for large-scale combustion power generation, and for small-scale gasification.

► Life cycle cost analysis was conducted to evaluate potentiality of rice husk use.
► The scenarios used rice husk for cooking showed a better cost effectiveness.
► While large-scale gasification and pyrolysis is less.
► In relation to GHG emission, the win–win scenarios are to use rice husk for cooking.
► Large-scale combustion and small-scale gasification also showed practical scenarios.