Results and discussion
3.1. Starch production in the business as usual (BAU)
The data of starch production plants collected from 6 starch plants and from literatures were compiled and calculated to get the average and uncertainty range as showed in Table 1. The results show that productivity from different plants is similar (the range is ±7% from average). Energy use has medium uncertainty range of ±30%. Water uses have high uncertainty range at ±50% because several plants have modified water cycle process in the system. Peel and sand waste also have high uncertainty range up to ±50% because it depends on the quality of feedstock from each season and region.